£)tate College of Agriculture St Cornell IBnibetiitg Stjjaca, gi. s. ILibtavjf Cornell University Library QD 271.P96 Organic analysis :a manual of the descri 3 1924 002 977 555 Cornell University Library The original of tiiis book is in tine Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924002977555 w opI^s dv ir)e. C)Gtrr)e Qulrjor QUALITATIVE CHEMfCAL A XA LYSIS. A Guide in Qualitalne Work, with data for Analytical <')]K-i-a1 inns and Labnratorj- Methods in Inorganic Chemistry, Jiy Albert B. Prescott and Otis C. Johnson, Professors in theUniversity of Mirhipfin. Eiflh rrris'-d mid i'nJ(ir(ierl editi, cloth $1.^5 FIRST BOOK IX QUALITATIVE CHEMTsTRY. TPiifJi rdifioii, revised. 12mo, cloth $1.50 ORGAKIC AMLYSI8: A MANUAL OF THE DESCRIPTIVE AND ANALYTICAL CHEMISTRY OF CERTAIN CARBON COMPOUNDS IN COMMON USE. QUALITATm; AND QUANTITATIVE ANALYSIS OF ORGANIC MATERIALS; COMMERCIAL AND PHARMACEUTICAL ASSAYS ; THE ESTIMATION OF niPUMTIES UNDER AUTHORIZED STANDARDS ; FORENSIC EXAMINATIONS FOR POISONS; AND ELEMENTARY ORGANIC ANALYSIS. ALBERT B. PRESCOTT, Ph.D., M.D., Director of the Chemieal Luboratori/ in the Vnicersily of JJirhlgaii, Author of " Outliius of Proximate Organic Analysis," "Qualitative C/iemioo/ Analysis,'' etc. FIFTH EDITION. NEW YORK: D. VAN NOSTRAND COMPANY, 23 MUKEAY AND 27 WARREN STREET. 1901. COPTKIGHT, 1887, Bt w. h. faehington. PREFACE. The operator in chemical analysis requires for his direction a system of descriptive chemistry, to be as nearly complete as possible. In resorting to the hand-books of general chemistry for the record of physical and chemical constants the analyst is often disappointed. It belongs, therefore, to analytical chemistry to furnish chemical descriptions with special precision, and this is a service promoting independent chemical work. As a mere changeful body of directions, giving the latest expedients in methods, analytical chemistry cannot claim to have educational value. But as an operative introduction to the character and deportment of compounds, analysis becomes a logical mode of study, fruitful of important results. For certain common carbon compounds it has been under- taken to furnish in this work, first, systematic chemical description, and thereupon the methods of analytical procedure, qualitative, quantitative, and for proofs of purity, all with liberal citations of the attthorities for convenience of further reading. In the references an order is observed as follows : (1) name of the con- tributor, {'2) year of the contribution, (3) volume and page, first of original and tlien of cmitemporary publications. Respecting the assumed peculiarities of organic analysis, it more and more appears that the diiferences between inorganic and organic analysis have been greatly overstated, just as, at earlier periods, the distinction between inorganic and ui-gaiiic chemistry in general was overdrawn. "With neai-er acquaintance it is seen that the limits of error in determination of carbon compounds are by no means always wider than those in analysis of metallic bodies. VI PREFACE. If tlie author of tins work liavc done anytliing at all to rescue the analytical chemistry of carbon compounds from a disjointed position in ciiemical hterature, he will have gained enough of recompense. He desires to make thankful acknowledgment of the encouraging favor which has been extended to his " Outlines of Proximate Organic Analysis"' since its issue in 1ST4. While his own promise of further publication has waited long for ful- filment, works of distinct value have opportunely appeared in different parts of the same held, and the flow of good contribu- tions has continued to increase everywhere. Organic analysis, as the determination of the unbroken compound's of carbon, no longer has an uncertain place in chemical learning. Albert B. Peescott. Univeesity of MirniGAx, Ann Arbob, October, 1887. ORGANIC ANALYSIS. ABSINTHIN. CooIL.^Oi . II.,() = 350.— The neutral princi- ple of the wormwood, Artemisia alisiiitliium. <)l)taineil by pre- cipitating- the hot-water extract of the leaves and tops by taunic acid, dryiuo- the precipitate with litliariie, and extractinjr with alcohol. The absinthin may be purified by tilteriui;' the alcoholic solution through animal cliarcoal, eva})oratiuy, and redissolviug in ether. Absinthin solidifies from yellow drops to indistinct crystals, nielting at l^i.)'^ C, and decomposing at higher temperatures. It has an aromatic odor and a very l)itter taste. It is almost in- soluble in cold water, slightly soluble in h(.it water, freely soluble in alcohol or ether; S(.ilubk' with a brown-red color iti tlie alkali hydrates. The potassa solution, when acidified by hydi'o- chloric acid, exiiibits a yellow-gi'een play of colors. — Concentrat- ed sulphuric acid dissolves it with brown cj. It is separated by distillation, if necessary preceded by saponification {e). From butyrates, by the insolu- bility of the barium acetate in alcohol (Butyric acid, e). It is estimated, as free acid, by acidimetry (/"), or gravimetric satura- tion ; as alkali acetate, by the alkalimetry of the ignited residue (yf). In Acetate of Lime by distillation and by special methods (p. 11). Commercial Grades and Imjnirities, p. 14. Vinegar, its standards of strength, impurities, and special tests, p. 15. a. — Absolute acetic acid (Glacial Acetic acid, Eisessig) below about 15° C. is a crystalline solid, forming transparent tabular masses, melting at 16.7° C. to a colorless liquid. An acid of 87 per cent, melts below 0° C. ; of 62 per cent, at —24° C. The absolute acid boils at 118° C. It has, at 15° C, the sp. gr. 1.0607 (water at 4° C.) (Mendelejeff). i. — Acetic acid has a pure acidulous taste and a penetrating, vinegar-like odor. When concentrated it is an irritant to the skin or tongue, and should be diluted before tasting. 0. — Acetic acid is soluble in all proportions of water and alcohol ; the absolute acid is soluble in all proportions of ether, and acts as a solvent for various essential oils, resins, camphors, phenols, and metallic salts. Diluted with water acetic acid gives an acid reaction with litmus. The metallic normal acetates are soluble in water ; silver and mercurous acetates less freely than the others. Perfectly normal alkali acetates are neutral in re- action, as shown by phenol-phthalein or litmus, biit potassium acetate is liable to be found alkaline, because slightly basic. Acetates in general lose acetic acid in hot solution, and in some instances by simple exposure, so that acetates exhale a percep- tible acetous odor, and gradually become basic. jSTon-alkali ace- tates, in solution, become slightly turbid, by formation of car- bonate, from carbon dioxide of the air. d. — Ferric chloride or other ferric salt, added not in ex- cess to solution of acetates, causes a red color l)y formation of ferric acetate. On boiling, a yellow-brown precipitate of basic acetate of iron is obtained, resolved finally into nearly pure ferric hydrate. The red liquid, before heating, is not decolored by adding mercuric chloride solution, nor taken up by shaking with ether, both these negative results giving distinction from Thio- cyanic acid. The color is destroyed by adding sulphuric or hydrochloric acid — a distinction from Meconic acid. — By hot digestion with sulphuric acid and alcohol, ethyl acetate, or ACETIC ACID. 9 acetic ether, is formed, recognized by its penetrating, fragrant odor. This test is most efficient when the dry acetate, obtained from acidulous Hqnid by nentrahzing with lixed alkali and eva- porating, is treated with an equal quantity of alcohol and a double quantity of sulphuric acid, and heated or distilled. The odor of other ethyl esters is liable to be mistaken for this. — "When dry acetates are sti'ongly heated in a test-tube, carbon is separated and acetone, C.jHy(), is evolved, capable of recognition by its odor. — By ilistfllaiion of acetates with phosphoric or sulphuric acid, free acetic acid is obtained, with its characteristic odor. — Acetic acid is a stalde compound, not oxidized by chromic acid nor by permanganates. e. — SejM rations-. — Aqueous solutions of acetates, if kept slightly alkaline with fixed alkali, can l)e concentrated without loss of acetic acid. The free acid distils very slowly, and its quantitative distillation requires thorough treatment. In distil- ling from acetates, phosphoric or sulphuric acid, or oxalic acid, is to be added, in sume excess of the (quantity needful to form nor- mal salts with all the leases present. To obtain all the acetic acid it is necessary to distil to dryness, adding water and repeating several times, until the distillate ceases to be acid to litmus. When various organic matters are present, it is therefore usually better to displace with phosphoric acid, avoiding the action of sulphuric acid in distilling to dryness. Care is to be taken that the phosphoric acid is strictly free from xolatile acids, and that salts of volatile acids other than acetic are not pi'esent. If hy- drochloric acid or its salts are present, the addition uf sufficient silver sulphate insures the retention of the chlorine. Further details respecting quantitative distillation are given under/'. To obtain the acetic acid of basic acetates insoluble in water, it is preferable to transpose them to alkali acetate by digesting with hut solution of sodium carbonate, filti'ring, and exhausting with hot water. The same oi)eration may witli advantage i)re- cede distillation in the case of lead acetate. Ethereal acetates, such as etljyl acetate, do not give up their acetic acid by dis])lac- ing it with a non-volatile acid, but require hrst to lie sapi'uitied by an alkali, when the alkali acetate is treated as liefore de- scribed. The saponification is effected by digesting with some excess of a solution of potassa in alcohol free from acetic acid, when all the alcohol may be removed liy evaporation. Also, a volumetric estimation of the acetic acid of etliercal acetates )nay be readily and exactly made liy saponifying with a known quan- tity of alcoholic potassa (see/'). NELbON M. lo ACETIC ACID. f.~Qiiiiiit!tiifii^i\ — In simple dilution with water, the spe- cific i;-ravitv (jf iicetic acid, if closely taken, is a practical >le indi- i'ation t)f ])crcentai;e, according to tables of accepted authority, hcariui;- in mind that acid of about It! per cent, ciiinciik-s in density with acid of 'JO per cent. Even within the range to winch it applies, the hydrometer is not exact enongh, unless cor- rected in its reading liytlie analyst himself. — Saturation nietliods id' estimation are to l)e preferred, especially that liy volitmctric sdhition of h.xed alkali. Phenol-phthalein is the best indicator, Init litmns will ser\'e. CoLjred li(puds may be diluted so as to show the phenol plithalein indication. If (i.doil grams ^ : Am. C/ifiii. Jour , 7, 2(i 12 ACETIC ACID. fifth to tenth hag, fairly representing both large and small pieces, and inclosed in rubber bags or air-tight jars while sent and held for analysis. The moisture is always to be determined in a portion taken as soon as the sample is opened to the air. The sample is then pulverized and sifted in preparation for the ana- lysis. Then a prepared portion taken parallel with that sub- jected to analysis is dried for estimation of its moisture, from "which the percentage of acetic acid is at last corrected for mois- ture, whether for the figures on a dry basis, or on the air-dry basis of the primary samples (Stillwell and Gladding). Crystal- lized acetate of calcium contains water of crystallization and is efflorescent ; the product " acetate of lime " may gain or lose water in the air, but in paper or wood packages it is likely to lose. (1) By (listiUation of the acetic acid. The most trustworthy method. Of the prepared sample 5 grams are dissolved in 50 c.c. of water, at least 25 grams of glacial phosphoric acid are added, and the liquid distilled, repeatedly adding water, not per- mitting tlie liquid to be reduced to dryness, and persisting until the distillate ceases to have an acid reaction, or the retort to smell of acetic acid. According to Messrs. Stillwell and Glad- ding, if the retorted liquid be not reduced too low, not more than traces of hydrochloric acid can be carried over from chlo- rides, and tlie excess of phosphoric acid prevents production of insohil)le calcium phosphate. All distillation of hydrochloric acid can be prevented by adding silver sulphate in the retort. JSTitric acid must be tested for. Fresenius (ISYS) and Endemann (1876) describe apparatus by which steam is introduced into the retort, in a current of regulated force, for continuing the distilla- tion. The total distillate is made to a desired definite volume, an aliquot part is measured out, phenol-phthalein added as an indicator, and titrated with standard solution of alkali (p. 10). (2) Methods depending on the quantity of soluhle lime salts ■present. Of these methods the one given by Fresenius (1874, ^d^ere cited) is one of the best, and is adapted to the assay of pure grades, free from acid empyreuma and from magnesium salt. Of the sample 5 grams are treated with about 150 c.c. of water in a quarter-liter flask, 70 to 80 c.c. of normal solution of oxalic acid added, and the mixture diluted with M^ater to the 250 c.c. mark. To compensate for the volume of the precipitate 2.1 c c. of water are added above the mark. After being shaken and standing for some time the precipitate is filtered out (through a di-v filter). Of the filtrate 100 c.c. are titrated with normal ACETATE OF LIME. 13 solution of alkali for acid as acetic acid. Then another portion of 100 c.c. is treated with calcium acetate to precipitate all the excess of oxalic acid. The calcium oxalate i>recipitate is filtered out, washed, tlried, igaiited, weighed as calcium carbonate, and the indicated quantity of oxalic acid calculated into its equiva- lent of acetic acid. The total acid as acetic acid in ] 00 c.c., minHs the oxalic acid as acetic acid in 100 c c, equals the true acetic acid in 100 c.c. of filtrate — that is, in f of the sample as- sayed (or in 2 j;-rams). (3) A method proposed by (tobel' is given as follows : For the titrations a solution of soda, of which 100(.t c.c. r= 100 grams absolute acetic acid ; a solution of phosphoric acid which titrates to phenol-phthalein of a strength equal to the soda solution ; and a solution of hydrochloric acid which titrates to litmus of a strength equal to the soda solution. A weighed quantity of the acetate under assay is treated with some measured quantity taken as an excess of the standard phosphoric acid ; the mixture evapo- rated t(i dryness ; the residue treated with watei- and evaporated again, and until the odor of acetic acid is no longer obtained ; the residue then treated with water and the mixture titrated for excess of phosphoric acid, with the standard soda, using phenol- phthalein, and noting the result in equivalent of acetic acid. Subtracting this figure from that for the acetic acid represented Ijy the phosphoric acid first added, the difference is the figure for the acetic acid in the acetate taken — subject, however, to cor- rection for free lime and lime carbonate in acetate of lime taken for assay. By titrating a weighed portion with the standard hydrochloric acid, adding an excess, expelling carbon dioxide, and bringing back to the neutral tint of litmus with standard Soda, the acetic acid ec.piivalent to the unsaturated earthy bases is found, and deducted for the coia-ection. A rapid method of assay, which has been much used, but is apt to give figures too higli, is carried as follows: A weighed <£uantity of the acetate of lime is supersaturated with a known (j^uantity of sodium carbonate in solution; the pi-ecipitate filtered out and washed ; and the alkali of the total filtrate estimated as soilium carlionate by titration of an alicpiot part. The loss of sodium carbonate due to the removal of acetic acid (and acid empyreuma) in the precipitation is calculated into acetic acitl, and figured upon the quantity of acetate of lime taken. — Blaik (Isyn, where cited) obviates the difficulty of the color of the ' 1884 : Repert f. anal. Chem., 3, 874 ; Zeitsch. dual ('hem., 23, 2l.i4. 14 ACETIC ACID. solution b}' filtering it through aniuuil charcoal, and then obtains good results l)y this method. g_ — Coiiiirwrcial (rrales uiid (Jommon Imj>ui'if''i's. — Tlie strengths of acetic acid have been designated by a " JS(o.," alto- gethe'r ditt'ereut from vinegar numbers, but probably originatiiig, under the British excise system, in the number of parts of four per cent, vineii'ar producible by dilution.' Thus No. S acid is that which diluted to eight parts will jiave about four per cent, strength. The two grades nundjered on this system, in this coun- try, are "No. tS" and "No. 12." Interpreted according to oi'igiiial intent, therefore. No. 8 shoiild be of 32 per cent., and No. 12 of iS pel' cent, strength. Dr. Squibb finds that the best qiuihties of No. S acid actiially prove of near :H)';l, strength, bearing laljel mark of s.g. 1.040 ; the poorer qualities of No. 8 ai-e near )>:>■! strength, and issued without a gravity mark. No. 12 acid is less common, and often runs from 38 to 40 p.r cent, of real acid. — Tlie strengths of vinegar numbers refer, in the British custom, to the numlier of grains of dried sodium carbonate neutralized by one Imperial fluid-ounce. i-Na/'Og : ("oH^O.-SS : CO::! : 1.132. The mnnber X 1.132 = grains absolute acid per fluid-ounce (of grains 437.5 X s.g.) The numlier x 0.2.59^ grams alisolute acid in 100 c.c. vine- gar. — In this country vinegar numbers have been grains of sodium bicarbonate neutralized by one fluid ounce, wine mea- sure. NaHCOg : ( 'oH/.*,, : : 84 : Ob : : 1 : 0.7143. The number x 0.7143 = grains absolute acid per fluid-ounce (of grains 455.7 X s.g.) The number X 0.1567 = grams absolute acid in 100 c.c. vinegar. Much of the " Glacial Acetic Acid " of commerce is not over 75 per cent, of real acid (iSyDiBB). It can easily be furnished of 99-j- per cent., as required by U. S. Ph. Of impurities in ordinary acetic acid, the more common are mineral acids, especially hydrocldoric, empyreumatic bodies, and metallic salts. Empyreuma, and other foreign bodies having odor or taste, are recognized by these senses after neutralizing with potassa or soda. " When diluted with flve volumes of distilled water, the color caused by the siddition of a few drops of test-sohrtion of permanganate of potassium should not be sensibly changed by standing five minutes at the ordinary tem- perature (absence of empyreumatic substances)." — U. S. Ph. According to Dr. Squibb,' when 1 c.c. of the acid, diluted with 5 ' Squibb, 1883 : Ephemerin, i, 258. = 1883 : Ephemeris, i, 260. I'lXEGAR. 15 c.c. distilled water, is treated with 3 di-ops of dccinormal solu- tiuii of permanganate, in eoniparisou -H-itli the same addition to the distilled water, if the color does "not heeonie fully hrown " within ten minutes, it is " a, \ery good aeid indeed," but the glacial acid " should stand this niuditication of the iierniaiiga- uate test for more than an hour." In vniegai' the most eonmion impurities are (1) free mineral acids, and (2) empjreumatic bodies (in " wood vinegar "'). Be- siiles, various made-up vinegars, and forms of diluted' acetic acid, are suljstituted for or added to cider-vinegar. The absence of/'/w iiiiiicrdi 0(J40 ^ per cent, of free mineral acid, as Md})luiric acid. Using the factor (1.00364, the statement is obtained for hydro- chloric acid, etc. Free sulphuric acid, in absence of chlorides, may be separated and determined as follows : loo c.c. are evapo- rated on the water-bath nearly to dryness, ti-eated with about 100 c.c. of alcohol, the mixture filtered, the alcohol evaporatiMl off, and the residue diluted for the gravimetric estiniatit^m of the sulphuric acid in it, by precipitation with barium chloride. If chlorides be pi-esent in the vinegar, it is necessary to add siher sulphate before adding the alcohol, when both the free sulphuric and hydrochloric acids of the vinegar are estimated as sulphuric acid. It must be remembered that sulphates and chlorides are liable to be present in legitimate vinegars, and the simple reactions with silver and barium, as j)rescrihed for acetic acid, ai'e not applicable in tests of vinegars in general. But, according to Davenpokt," " in a pure cidej' viiiajar, nitrate of silvei', nitrate ' " Report of Inspector of Viiio^-iir of the City of Bosldri," 1884, p. 4 ; of Inspector of Milk of the same, l.SH."), p. 10. 1 6 ACETIC ACID. of barium, or oxalate of ammonium added after an excess of am- monia water, will neither of them give more than the slightest perceptible reaction." Also, " a drop of it in a loop of platinum wire, when ignited in a Bunsen lamp-flame, gives a pure potash flame without any yellow soda rays visible." "The addition of any practical amount of a commercial acetic acid to tone up the strength will give another color to the flame." Cider-vinegars yield a residue " always soft, viscid, mucilaginous, of apple flavor, somewhat acid and astringent to the taste." " If any corn glucose is present, the residue, when ignited in the platinum loop, will emit the characteristic odor of burning corn ; and if the glucose was manufactured with the commercial sulphuric acid derived from copper-pyrites, it will, as the last spark glows through tlie carbonized mass, emit the familiar garlic odor of arsenic." The percentage of solids in cidei'-v'uiegar, by weight of residue, is generally required to be as much as 1.5 per cent. Dr. Davenport (18S5) recommends that the legal limit be 2 per cent. " When 20 grams of the vinegar are mixed with 0.5 c.c. of barium nitrate test-solution (1 to 19) and 1 c.c. decinormal silver nitrate solution, the filtrate from the mixture sliould give no re- action for chlorine or sulphuric acid. When two volumes are added to one volume of sulphuric acid and then one volume of ferrous sulphate solution poured over, no brown zone should appear between the layers. The evaporation-residue from 100 grams should not exceed 1.5 grams. The residue should not have a sharp taste, and its ash should have an alkaline reaction." — Ph. Germ. The required strength of mnegars is given by U. S. Ph. of 1870 at 4.6'^; Br. Ph., s'.ll^; Ph. Germ., 6^'; the "proof vinegar" of British Excise. 6^, or English "No. 24." In exe- cution of the British law against adulterations of foods, the minimum limit of strength has been held at Zle alkaloids of the aconite group are salts, or esters, of benzdic acid (or a derivative of this acid), and are readily saponlfiahle hi; action of alkalies or strong acids, to some extent even by water with heat. And the saponitictition results in the removal of either benzoic acid or a derivative of benzoic acid, and the formation of amorphous alh/loldsm place of the crystallizable alkaloids sapo- nified. The tendency of aconite alkaloids to become amorphous, with diminished physiological activity, is explained by saponifica- tion. Tlieir liability to another and less obvious class of chemi- cal changes, leaving them still crystallizable and with little loss of physiologictil activity, is shown by the proof that, l>// act Ian of stranej acids, they suffer delnjdratlon and form, apo-alkfdolds. That is to say, alk/dles, with more or less readiness, and eveti hot digestion with water, cause saponification; and strong mineral acld.i, even concentrated organic acids in a degree, cause both saponification and dehydration to apo-compounds.'' ^^arious ' C. R. A. WRionx, in part with A. P. Luff, and with A.E. Menke, 1H77- 1879 : Jour. ('hem. Soc, 31, 143 ; 33, 1.51, 318: 35, :!S7, 390. P/kii: Jour. Trans. [3] S, l(-ii4iN 09=C„7li37N Og (0H)3 . OH. Atropine, and Cocaine, agree in being saponifiable allialoicTs easily gi\;ing up either benzoic acid or some near derivative of benzoic acid. (Atropine: Kraut, ls(i,"i. Cocaine : Lossen. 1865. Aconitine : Wright, 1877.) Among other saponifialile alkaloids, yielding acids of the aromatic group, are piperine, and certain vcratrnni alkaloids. ' In saponification by alkali, the benzoic acid or its derivative is left in com- bination with the alkali, from which it is obtained by acidulation. In saponi- fication by acid I he amorphous alkaloid is obtained in salt of the acid. ' Weight (1870), in his last contribution upon the aconite alkaloids, sVi'ongly inferred the existence of a "hypothetical parent-base, C33Hi7NOi2" =C2»H3!,NO,.(OH)3.0.(C,HsO). Juergens (1885. wli ere before quoted), by a modified process of extraction from the root, and thorough purification, ob- tained aconitine which, in elementary analysis, gave him numbers for C33H47XO]a. The alkaloid gave the intense numbing sensation upon the tongue, without a recognizable bitter taste. ^ Mandelin (1885), by investigations (without elementary analysis), con- cluded that aconine and pseudaconine are the same, so that, in his view, aconi- tine and pseudaconitine differ only by their acidulous radicals as found by Wright. ACONITE ALKALOIDS. 19 Tlie amorphous alJcaloids are found in the plant, as well as obtained by alteration of the crjstallizablo alkaloids during sepa- ration from the plant. The changes of dehydration to apo-alJcaloids, by action of acids, is shown by the following comparisons of rational for- mulae : Aconitine, C33H^3NOio=Co,H,5N07 (0H)3 . . (C^HgO) Apo-aconitine, C33ll4iJN'^Oii=Co6H35N07 (0H)0 . . (C7I-I5O) Aconine, CoeII.,,^^Oii=CouIT35XO„(OH)3 . OH Apo-aconine, Co^; HsyNO^o = CogHgsNO^ (O II)oO Psendaconitine, C3gH49NOio=C27H37NO^ (011)3. 0. (C9H9O3) Apo pseudaconitine, 03qH4-NO;ii ' =C27H37K05 (011)0. O.lCgHgOg) The natural alkaloid, japaeonitine, has the constitution of a sesqui-apo-derivative. Gh/ef Sources of the Natural Aconite Alkaloids. A. Napellus. root. "Aco- Aconitine. Aconine. Pseudaconitine ) in small propor- Pseudaconine ( tion, if at all. Picraconitine I (exceptionally \ present.) Pseudaconitine. Pseudaconine. Aconitine ) t,,, Aconine ^^ry little. nite" of U. S. Ph. and Ph. Germ. A. ferox, root. " Indian Aconite " " Nepal Aco- nite." Bish, or Bikh. " Himalaya root." Japanese aconite, root. A. lycoctonum^ root. A. anthora, root. A. paniculatum, root. Japaeonitine. Japaconine. Other alkaloids. Aconitine. Pseudaconitine. Amor ph. alkaloids. Pseudaconitine. Amorph. alkaloids. Picraconitine. ' A report of alkaloids from this plant, amorphous, and having an ener- getic effect like curare — Dbagendoeff & Spodn, 1884. 20 A CONITE A LKA L OIDS. The chief Aconite Alhaloids ; _f!i/iwinjvis, Crij.'itallisa.tion, and Aotivoty. Xame. Synonyms. Forinfila. CrystaJlization. Physiolog. effect. Aconitine. Cryst. aconitine. Napaconitine. CaH.sNO,, Crystallizable, when free, as well as in salts. Of typical aco- nite activi- ty- Pseudaconiline. Naiielline. b'eraconitine. Acraconitine. English aeon. C36H.,9NO,l, Base and its salts crys- tallize with difficulty. Approaches to or erpialsthe activity of aconitine. Japaconitine. Cryst. alkaloid ot Japanese root. CaeHsslSrjOj, Crystadizable both free and in salts. Closely resem- bles aconi- tine iu pro- perties and efliects. Aconine. Amorphous aco- nitine. A pro- duct of aconi- tine, by alkalies or acid's. C^cHs.NOii Amoi'phous, both free and in salts. Of far low- £v activity than aconi- tine. Bitter. Pseudaconiue. Aniorplious aco- nitine. A pro duct of pseud- aconiline, by alkalies. C„H4,N0„ Amorphous, free or com bincd. Of far low er activity than aconi tine. Bitter. Japaoonine. Amorphous alka- loid of Jap. aconite. Pro- duct of japaco- nitine. G^eH^NO.o Amoi'phous, free or com- bined. Closely resem- bles aconine in properties and effects. Pioraoonitine. Inactive, bitter al- kaloid of A . pa- nieulatum anti other species. 03lH.,5NO,0 Base cryst. with diifi- culty. Salts crystallize well. Bitter. Not poisonous. Pioraconine. Amorphous pro- duct of picraco- nitine. CjJii.NOB Amorphous. Bitter. Not poisonous. Apo-aconitine. Product of aconi- tine, by action of acids. C33H4,NO„ Crystallizable. Of the same activity as aconitine. Corresponding apo-derivatives, by action of acids on Pseudaoonitine, Aconine, etc. (See p. 19.) ACONITE ALKALOIDS. 21 For medifhial uses the U S. Pli. and Pli. (iemi. admit only the tiiberons rodt of A. Napelliis; the \\r. Pli., also U. S. Ph. of 1ST(», admit lioth " root " and leaf of A. EapcUus ; the Ph. Fran, authorizes tlie use of root and leaf of A. Napellus and A. ferox. It is understood that both Japanese aeonite root' and root of A. ferox are largely used for the manufaeture of medicinal alkaloid "aconitine." A. Sterkeanum contains ])oiRonous alkaloids. ^Jf"^^'^^ "f '"^^'"'"^ Aeon He AlhADiils. — Wkioht obtained, in 1S76, from A. Napellus only 0.03 ])er cent, of pure aconitine, and pnly i).07 per cent, of total alkaloids fiee from other matter. Again, from Japanese aconite roots o.is poi- cent, of mixed al- kaloids. JuEEoENS (18sri) obtained, by a modified Diiquesnel's process, of thoroughly purified aconitine (for elementaiy analy- sis) 0.ti2 per cent. Py chemical assays (Is.SM) Labokde and DuQUESNEL found in A. Napelhis root, of " crystalline alkaloids " from 0.05 to 0.40 per cent., averaging (I. in jier cent. ; of "amor- phous, insoluble substance " having'an ell'ect like aconitine in kind, "a few" tenths per cent.; and of "amorphous, soluble, bit- ter substance," about 1.5 ])er cent. Zixoefski,' working bv volu- metric estimation with J\Iayer's solution (probal)ly an Inexact measure of total aconite alkaloids) in A. Kapellus and other species, from the fresh leaf (calculated to basis of dry material) 0.73 to 1.3S per cent, total alkaloid ; from tJie fresh stalks, 0.25 to 0.9(1 per cent.; and from the fresh flowers, 1.51, 1.05, and 5.52 (!) per cent, total alkaloids. Hagee (ly08) re])0T'ted find- ing in the best commercial root of A. Na])ellus from 0.04 to 1.25 per cent, [total alkaloids]. ^(iuiBB (1.S.S2) found the leaf of A. JS^apellus to have only about one-ninth of the physiological effect of the same quantity of the rcxit. Cui.lamoee (1S84) found the action of A. ferox to be more intense in degree than that of an equal quantity of A. Napellns. The "aconitine " of the market may contain any mixture of the aconite alkaloids — fi'equently aconitine, jajiaconitine, pseud- aconitine, and tlie wholly amorphous alkaloids. Systematic phj'- siological assay of fotir commercial grades of " aconitine," bj' Dr. Squibb in lss2, in com])arison with good powdered aconite root, gave the following results : (1) Of unknown make had only the physiological potency of the root ; (2; " Ordinary," S times the strength of the same weight of the root ; (3) Pseudaconitine, 83 times the power of the root; (4) "( Crystallized," 111 times the ' Respecting Japanese and Chinese Aconites, see Lanugard, also Waso- vioz, 1880 : Archiv d. Pliar., 14, 217, and 15, 161 ; I'liar. Jour. Trans., [;i] 10, 149, 1020 ; Pror. Am. Pharm., 29, 170-183. ' Dragendorff's " WerLhbestimmung," 1874. p. 13. 22 ACONITE ALKALOIDS. effect of the root. If we accept "Wright's analyses, first above given, the total aconite alkaloids should have from 500 to 1400 times the potency of the same weight of root. Further, Dr. Squibb found that the article (4) was a nitrate containing not more than 80.7 per cent, of hydrated alkaloid. Aconitine was dropped in the last revision of the U. S. Ph. and in the last re- vision of the Ph. Germ. It is retained by Br. Ph. and Ph. Fran. The ceystallizable Aconite Alkaloids are identified by their organoleptic effect (5), the agreement of their precipitations {d, p. 25) and solubilities (c), and by yielding benzoic acid or its derivative when saponified (p. 18, and under _/'). The amoephous ALKALOIDS of the aconites are distinguished from the crystalliz- able ones by greater solubilities in water (e), greater reducing power {d\ greater bitterness without lip-tingling effect (5), and by not yielding benzoic acid or its derivative when saj^onified (under/'). Aside from sources and accompaniments, amorphous aconite alkaloids are, with difliculty, identified by a general agree- ment of precipitations (d)^ solubilities (5), and melting points {d\ Aconite alkaloids are separated from the aconite roots, indeter- minate matters, etc., by assay processes of extraction (e) ; from tissues, etc., in analyses for poisons i?i the iody as directed, with procedure for identification (under e). The active alkaloids are separated by crystallization. The total ahvaloids of aconite are estimated gravimetrically, or volumetrically (f). Separate estimation of the active alkaloids is proposed, by saponification and determination of the quantity of benzoic acid and veratric acid (/). For J >ractt'ea.l estimation of active a/Ialoids alotie,hj physiological assay, under i, p. 23. For commercial grades and values, f/ sources, p. 19. «■ — Aconitine crystallizes anhydrous in rhombic or hexa- gonal tables, appearing in snow-white fiakes; and its salts crystal- lize well. Jajidctmitine crystaUizes well, both free and in its salts. Pseudacoiiitive and its salts do not crystallize without very careful treatment ; from ether, or better a mixture of ether with petroleum benzin, it forms needles or sandy crystals, with 1 aq., but unless the concentration be extremely sIom- only cau- liflower-like effiorescence or a varnisJi layer will be obtained. The nitrate crystallizes when treated with care. Pier aconitine crystaUizes with difliculty as a base ; its salts easily form good crystals. Aconi ne, j^seudaconine, SLuAjajxiconine, with their salts, are white, powdery solids, strictly uncrystallizable. The apo- aUmloids agree in crystallization with the aconite alkaloids from ACONITE ALKALOIDS. 23 "which they are formed — apo-aconitine being crystallizable, and apo-aconine amorphous. The iir. Ph. describes " aconitine " as " a white, usually amorphous solid '' ; the Ph. Fran, as " colorless rhombic tables.'' As found in thu shops, " aconitine" (mixed allvaloid) is usually amorphous, often colored, sometimes in thin, partly etttorcsced plates, sometimes in large needles. Aconitine melts at l^-\^' 0. {\NviiGii'v) ; jm^ndnconUine loses water of crystallization at 80° C, melts at 1U5° C, and de- composes at about 130° C. ; jajxicunltuie melts at 1^5-1° to 186° C. ; aeon i lie melts at 130° C. ; pseudaconine at 100° C. ; jiicraconitine does not melt on the water-bath; iipo-avonitlne melts at 183° C These alkaluids all preserve a constant weight on the water-bath ; when ignited they burn away slowly. As to sublimation, and microscopic identification of the sublimate, see Helwig (1801:) ' and Blyth (1878).' h. — Aeoii.it I lie, in solutions dilute enough to be safe for the trial, causes a tingling and characteristic numbness of the Kp and tongue and pharynx, commencing after a delay of from a minute to a c^uarter uf an hour, according to the extent of dilu- tion. Dr. ISyuiBB' found that 0.006 gram ((J. 1 grain) of good aconite root, in a solution of 3.7 c. c. , or 1 fluid-drachm (of its soluble constituents), held in the anterior part of the mouth (pre- viously rinsed) for sixty seconds, and then discharged, gave the tingling sensation (as a rule), cummeneing within ITi minutes and then continuing for a quarter or a half an hour. When the same vc^lumc of solution was inaseudaronitl'neioY a man is placed l)y Mandelin (1SS5) at 0.0001 gram (-j-^-jj grain) in a single dose, and O.oOdS (y^-jj- grain) during ^2A hours. Of Duquesnel's "aconitine" Sequin (1878) gave 0.0005 gram (rir g™ii) as a single full dose ; and the same Cjuantity of liot- tet's " acunitine " "was given as a single maximum dose by Gtjb- LEE (1880). Of commercial crystallized "aconitine " of unknown strengtli, current authorities limit the first (or trial) dose at about O.OOUii gram (^-^j grain), but this is double the dose of absolute aconitine declared by Mandolin, as above. — The smallest fatal dose of absolute aconitine, or j^seudaconitine, for a man is placed by Maxdelin (1885) at 0.003 gram (near t,V grain) ; for warm- blooded animals, ().()(M.)05 to 0.0(10075 gram per kilogram of body- weight ; for frogs, 0.0012 to 0.0024 gi'am per kilogram of body- weight. Bltth (1884) deduces that, of French aconitine or Morson's aconitine, by the mouth, tlie least fatal dose for a man is 0.0o2 gram (Jj grain), ecjual to 0.000028 gram per kilogram of body-weight ; for the cat 0.000075 to 0.00009 gram per kilo- gram of body- weight. "With the frog (Dragendoeff) 0.002 gram [aconite alkaloid] causes paralysis of the hind legs in a few minutes. Dilatation of the pupil is not a constant effect of aconitine, but usually occurs in some stages of its action. PseHiia<'onltine,\i\(^efm\te\j repi'esented by the old " napel- line," undoubtedly has nearly or quite the same physiological effect as aconitine. Cullamoeb (1884) found the action of Aconitum ferox root to be similar in kind to action of A. ISTa- pellus. The vjJwlly amorplious aconite alkaloids, aconine and pseud- aconine, have but in a very low degree the specific activity of aconitine. Husemann (1884 : Pliar. Zeitung) found aconine to have a toxic effect on frogs and mice, an effect 300 to 400 times less than that of aconitine. "Wright stated of aconine and of irritation and lachrymation, lasting for hours ; whilst similar particles, if in- haled, produce great bronchial irritation, or profuse sneezing, and considerable catarrh or ' sore tliroat,' according to the part where they lodge." — U. R. A. Weight, first report. ACONITE ALKALOIDS. 25 pseudaconiiie that it is of extremely bitter ta.ste, hut does not pro- duce the sl'ujldeH Iij>-tuio-(i/ltdoidi! of aooiiite have the effect of the alkaloids from which tlicy are derived. Apo-aconitiue has the full physio- logical activity, aud apo-aconine is an inactive hitter. Pieriteoiiithie is very bitter, and quite destitute of the spe- cific potency of aconitine. Aconitine, and its allied bases, have a decided alkaline re- action, and neutralize acids perfectly, forming salts more stable than the free alkaloids. The nitrate is a favorite salt for crystal- lization. c. — Aconhine is very little soluble in cold water (in 72fi parts, JuEEGEXs, 1SS5), but dissolves in hot water, and in alcohol (24 parts of 90^0 alcohol), ether, benzene (sparingly when cold), freely soluble in chloroform, soluble in amylalcohol (Deagendoeff), does not dissolve in petroleum benzin or carbon disulphidc. It requires 2S0tJ parts of petroleum benzin for solution (Jueegens). It is not dissolved from aqueous solutions of its salts by ether, or chloroform, or benzene. — Pnemdacuvltine is sparingly soluble in water, more freel}' soluble in alcohol and in ether than aconi- tine is (Weight). Jajiaconitine is soluble in alcohol and in ether; jpicraconitine is very sparingly soluble in water. Aco- nine is freely soluble in water, alcohol, or chloroform, almost in- soluble in ether, especially when free from alcohol (AVeight). Pseudaconine dissolves in water, or alcohol, or ether (Weight). Afo- aconitine and apo-aconine dissolve in ether. d. — The most delicate and distinctive test for tlie active al- kaloids of the aconites is the physiological test for lip tingling, described on p. 23. Aconite alkaloids — namely, aconitine and pseudaconitine — and their amorphous products, aconine and pseudaconine, are precipi- tated, from their nearly neutral solutions in hydrochloric acid, as follows (Weight) : by " bromine water, iodine dissolved in potassium iodide, tannin, gold chloride, mercuric iodide dis- solved in potassium iodide, mercuric bromide in potassium bro- mide, and mercuric chloride. These precipitates dissolve on more or less largely diluting the fluids, the aconine precipitates being more soluble than the corresponding pseudaconine ones, whicn again, save in the case of tannin, are marl^•edly more soluble tnan those of aconitine or pseudaconitine. Other things being equal, the mercuric chloride precipitates are more soluble than those formed with mercuric bromide, which are more solu- ble than those thrown down by mercuric iodide. Aconine is 26 ACONITE ALKALOIDS. not precipitated by sodium carbonate or ammonia, save when the solution is evaporated almost to dryness, so that an oily liquid separates along with the solid sodium or ammonium salt ; pseud- aconine behaves similarly, whilst aconitine and pseudaconitine are but sparingly soluble in excess of these reao;ents. Strong caustic potash precipitates all four bases, the aconitine and pseud- aconine precipitates being only sparingly soluble in excess, the pseudaconine being much more readily soluble on diluting the Huid, and aconine being precipitated only in very concentrated solutions. Platinic chloride throws down precipitates only with strong solutions, especially with pseudaconine and aconine, the precipitates in all cases dissolving readily on dilution. — It is noticeable that jjicraconitine is scarcely distinguishable from acouitine in these reactions, excepting that with sodium car- bonate and ammoiiia it is precipitated much less readily, the precipitate being formed only in concentrated solutions, and dis- solving readily on dilution." Further (Wright), the amorphous alkaloids, aconine and pseudaconine, are distinguished from the crystallizable aconite alkaloids by greater reducing powers — reducing silver (slowly) from hot solution of silver nitrate or of ammoniacal silver ni- trate ; and gold from the gold chloride precipitate, on standing. Aconine reduces Fehling's solution on boiling, a distinction from pseudaconine, which does not. — Both crystallizable and amorphous aconite alkaloids (like the ptomains) promptly reduce ferricyanide of potassium, as shown by a drop of ferric salt solution. Lim'iU. — The precipitation by iodine in potassium iodide is distinct (on a glass slicfe) in one grain of a solution of the al- kaloid in 5(),0U(i times its weight of water (Woemley). With the gold chloride, one grain of a solution of the alkaloid in 6,000 parts yields in a little time a quite fair precipitate ; diluted to 20,000 parts, after some time a just perceptible turbidity. With bromine in hydrobromic acid, one grain of a solution of one part of the alkaloid in 10.000 parts of water gives a quite fair precipitate (Woemley). The limit of the precipitation by potas- sium mercuric iodide (Deagendoeff) is about 0.0009 gram in 1 c.c. of acidified solution, acidulation diminishing the solubility of the precipitate. Phosphomolybdic acid gives a yellow pre- cipitate, changing to blue on standing, and dissolving blue in ammonia — 0.00007 gram alkaloid in 1 c.c. water acidulated with sulpliuric acid giving a distinct precipitate after half an hour (Deagendoeff).' ' A test for completely purified aconitine is given by Jueegens (1885) as follows : The particle of solid alkaloid, or residue of its solution, on a glass ACONITE ALKALOIDS. 27 The color reactions by acids, Froehde's reagent, etc., are so widely varied liy alterations and differences (impurities) of the aconite alkaloids that no deijendencc can be placed npon them, unless the residts are interpreted l>y results of control tests made by the analyst upon strictly parallel aconite products.' e. — Si'paiudioiifi. — Aconite alkaloids are not vaporized, but are very slowly saponitied, by concentration of their aqueous so- lutions on tile water-bath. Such concentratitm should, if pos- sible, be done in neutral solution, and action of alkalies is gene- rally more destructive than action of acids. Dr. Squibb stated {18S2) that the attenuated solutions of aconitine, and those of tluid extract of aconite, diminished in strcngtli, shown by physio- logical action, after the second day ; and in four days, the weather being warm, they became quite inert, tiie growth of cryptogams keeping pace with the loss of strength. — Aconite alkaloids can be shaken out or extracted fn.im slightly alkaline (not from aci- dulous), cold, aqueous solutions, l)y ether, chloroform, etc., ac- cording to the solubilities in thcsu respective liquids, given on p. 2."i. xVnd from solution in these ]i(|uids acidulated water takes up the alkaloids In sejiaratiuii, fro)ii aconite /v;r;?', the process of Duquesnel, modified by Wriglit and otherwise varied in details, well serves the purpose of an assay. The powdered root is percijlated to exhaustion with alcohol (not acidulated) This is done much the best by the continuous operation of an extraction apparatus. The solution is concentrated, preferably by boiling under reduced pressure, to remove the alcohol, the liquid diluted with water to a limpid state, and just acidulated with tartaric acid. One part of tartaric acid to 100 parts of the root is the propor- tion of Duquesnel's process, in which the acid is added to begin slidf, is treated with a drop of water acidulated with acetic acid, and a minute fragment of potassium iodide added, when presently rhombic tables appear under mierrisfO|jic inspection. Obtained with 0. 0000.15 gram. ' When aconite is dissolved in hot phosphoric acid previously fully concen- trated on the water-bath, there appears, according to the purity of the alkaloid, a violet to brnwn color — at all events crystallized aconitine is but feebly colored by the phosphoric acid, and eryslallized aconitine nitrate is not colored at all. The yellow color bv sulphuric acid diminishes in the same way (Fluokiger's "Pharm. Chem.," iHTfl). Concenlraled aqueous phosphoric acid dissolves aconi- tine, giving on the water-bath a beautiful violet color, remaining f(ir a day in the cold — a distinction from "pseudaconitine" (that is, " napelline," " Morson's aconitine," or "English aconitine"), which remains colorless (ITeppe's "Die chemischen Reactionen." 1S7.5. from TTunscnMANV, Hasselt, IIerdst, Praao). "I found the color vcllow at 80° 0., reddish at 89° ('., violet at 13.<)° C'— Dra- GENDORFF in " Ofganische Giftc," 1R72. .Tuergenb (1HH5) obtained purified aconitine which gave no color reactions with phosphoric acid, sulphuric acid and sugar, or phosphomolybdic acid and ammonia. 28 ACONITE ALKALOIDS. with. The hqiiid is now filtered, by help of the filter-pump, and the resinous residue washed with a little water. The solu- tion is now washed several times with ether, the total etherial washings being washed with a little water slightly acidulated with tartaric acid, returning the aqueous washing to the acidu- lous solution. Sodium carbonate is now added to a clearly alka- line reaction, and the liquid shaken out with ether to complete exhaustion. The etherial solution is concentrated in a flask as far as it may be witliout formation of residue, and then washed several times with water slightly acidulated with tart;iric acid ; seeing- that the reaction is distinctly acid after shaking with the ether. The aqueous liquid is at once made barely alkaline by adding sodiuiii carl)(jnate (if deemed advisory, is washed once with light petroleum benzin), and then shaken out with ether, re- peatedly, as before. The united etherial solution is concentrated,, at last spontaneously, to crystallize ; or when partly concentrated a little light petroleum benzin is added and the solution set at rest to concentrate and crystallize. In either case all resinous residues are thoroughly washed ■with ether by the filter-pump, anlum<>ti'u' estimation oi (total) alkaloids of the aconites are made by ]\Iayer\s solution — witli approximate I'csnlts — as follows (Dkac;exdorff) : The solution is made (by a previous approxi- mate assay) to contain one ]iart alkaloids to 150 or 2(10 parts of water, and slightly acididated. The end of the reaction is fotmd by filtering a dnip or two, through a very small filter, upon a watch- glass, and adding a drop from the burette, when, if turbidity ap- pears, file watch-glass and filtei- are drained and rinsed with a few drops of water into the alkaloidal s(.ilution, and another ad- dition made from the Imrctte. Each c.(/.of the Mayer's solution indicates t).():>7i gram of the alkaloid (empirical), the amount to be increased by U.UUOU.j gram for each c.c. of the total liquid containing the precipitate. The results are near enough indica- tions of tiie ijuantity of total alkaloids to be prai-tically useful for commercial assays of aconites and their preparations — pro- vided always that (piantity of total alkaloids could serve a com- mercial purpose in absence of any index of the proportion of amorphous alkaloids. A method of entl nin.tlon of the crijutdirizatilc and ■phijahilngi- callij act'i iy>, nthitluUlK was ])ro|)osed by ]\[r. A\"eriht in 1S7T,* to be done liy saponification, and estimation of tlie resulting iicnzoic ' For the instructive aeeoiint of analysis by Drs. DrrRi!: ami Stevenson, inihe Lampson case, in Lnmldu, in li-<8'3, see Ttie Lmici'l, Jiarcli IM, ls«2, p 455 ; Wltarton and Slllir!, •' Med. Juris.," vol. 3, 1884, Pliilu. od., p. 034. •' '-Geriohll Ciiemie," 1872, p. 62. ^Phar. Jour. Trans., [3] 8, 104-178. 30 ACONITIC ACID. acid, and dimethylprotocatecliuic acid (see p. 18). Saponifica- tion is made complete by boiling alcoholic potash, or by water with digestion at 14()°-150° C, in sealed tubes. Distilling with water separates the benzoic acid from the dimethylprotocatecliuic acid. The weight of the benzoic acid is \ that of the aconitine. The weight of the dimethylprotocatecliuic acid is |- that of the pseudaconitine. g. — Commercial grades and values. — An elaborate pharma- cological valuation of several brands of aconitine was made, using frogs, rabbits, dogs, and pigeons, by Plugg-e in 1882." It was determined that retit's "nitrate of aconitine" was eight times stronger than Merck's " nitrate of aconitine," and one hun- dred and seventy times stronger than Friedlander's ; also, that " German aconitine " is variable. Of the samples examined by Plugge he found the following order of diminishing strength : " Nitrate of aconitine " : (1) Petit's, (2) Morson's, (3) Hottet's, (4) Hopkins and Williams's " pseudaconitine," (5) Merck's " aco- nitine nitrate," (6) Schuchardt's '• aconitine sulphate," (T) Fried- lander's " nitrate of aconitine." These figures iimst not be taken as indicating the strength of all the alkaloids furnished under these respective brands. Dr. Squibb (p. 23) found tlie relative strength of four articles to be, in proportion : Duquesnel's " crystallized aconitine," 111 ; Merck's " aconitine from Hima- laya root " (pseudaconitine), S3 ; Merck's " aconitine " (ordi- nary), 8 ; unknown " aconitine,'^ 1 ; the powdered root of A. JSTapelhis, 1. — The " Aconitine japonicum " of Merck claims to be japaconitine. ACONITIC ACID. HgCgHgOg = 174. —Found in Aconi- tum Nnpellas (monks-hood) and other species of Aconitum, in Deljdi/niuiii Consolida (larkspur), in JEguisetum,, Helleboras niger, AcKRlea Mdlefoliutn (yarrow), Adonis vernalis, and other plants. It is a product of citric acid by heat, and occurs in various citric acid concentrated juices of commerce, in sugar- cane juice," and in the scale from sorghum-sugar pans,' but it is not manufactured for use. — Crystallizes in white, warty masses, or very slowly in four-sided plates or hard needles. It darkens at 130° C, melts at 140° C, and boils at 160° C, when it gradu- 1 Archiv d. Phar., [3] 2o ; Am. Jour. Phar., 54, 171. Also, on this ques- tion, Harnack and ^Fenxickb, 1883. 2 Behb, 1877 : Denf. Chem. Ges. Ber., 10, 351. ^ H. B, Pabsons, 1882 : Am. Chem. Jour., 4, 39 ; Jour. Cliem. Soc, 42, 766. ' A com TINE. ^^SCULIN. 3 1 ally decomposes into Itaconic acid, CgllgO^ , and carbon dioxide. Citraconic anhydride and other pyrocitric acids occur at higher temperature. Aconitic acid is soluble in water, alcohol, and ether ; its solutions have a strongly acid reaction, and a purely acid taste. It is tribasic and forms three classes of salts. — Free aconitic acid solution is precipitated by solutions of mercurous nitrate and lead acetate, and alkali aconitates are precipitated by lead nitrate, silver nitrate, and ferric cldoride (red-brown). Calcium aconitate is only sparingly soluble in water. Phos- phorus pentachloride, with heat, gives a cherry-red hquid, de- colored by water. Nitric acid in boiling solution is deoxidized with evolution of brown vapors. Aconitic acid is prepared from plants in which it exists as calcium salt, by evaporating the clear decoction to crystallize. The crystals of aconitate of calcium are dissolved by slight acidu- lation with nitric acid, and precipitated by acetate of lead, and the lead salt decomposed by hydrosulphuric acid. The residue of the filtrate is taken up by ether, and the acid remaining on evaporation of the ether is dissolved in water and crystallized in vacuum over sulphuric acid.' It is also separated from im- purities by adding (to the dry mixture) five parts of absolute alcohol, then saturating the filtered solution with hydrochloric acid, and adding water, when aconitate of ethyl will rise as an oily layer, colorless and of aromatic odor. This ether may be transposed by potassium hydrate. Aconitic acid may be best obtained, artificially, from citric acid." ACONITINE. See Aconite Alkaloids. .^SCULIN. CigHieO9=240 (Schiff, 1870; Liebeemann, 1880). — The bitter principle of the bark of the horse-chestnut (JSsculus hippocastanum). Not identical with gelsemic acid ("WoEMLEY, 1882). Obtained by precipitating a decoction of the bark with lead acetate, filtering, and, after removing the lead from the filtrate by hydric sulphide, concentrating to a syrup and allowing to crystallize. It may be purified by repeated crystallization from alcohol and finally from boiling water. Crystallizes in snow--svhite, very small needles, arranged in ' BucHNEB : Pliarm. Repert., 63, 145. A method of separation from Equisetum was given by Baup in 1850 : Lii-hig's Annalen, 77, 393 ; Jahr. d. C^iera., 1850, 373. - Pawollei-k, 1876: with process, LieUcfs Annalen, 178, 150; Jour. Ghem. Soc, 29, 375. 32 ALKALOIDS. fflobukr masses or in the form of fine powder. Tliey have the composition Ci-.IlieOg 21120, and lose lUIoO at 110° C, and the rest of the water upon melting at 1(10° It is odorless, slightly bitter, and reddens litmns. ISoliible in 6i2 parts cold and 12]- parts boiUng water, in about 100 parts cold and 21 parts boiling alcohol ; insoluble in al isolate, sHghtlj soluble in ordinary ether ; soluble in dilute acids and alkalies. The aqueous solution (con- taining the merest trace of the glucoside) exiiibits a distinct blue fluorescence, wliich is more marked if well-water is used, and is destroyed by addition of acids. The alkaline solutions are yel- low, but exhibit a blue fluorescence. It is dissolved by chlorine water with red color which changes tlirough brown-red to yellow. Nitric acid forms a yellow solution with it, which becomes red upon addition of excess of potassium hydrate. Boiling with dilute acids converts it into CBHCuJet'ni, (3gIIg()4,' and glucose. Ferric chloride colors its solutions green, it reduces alkaline cupric solution upon boiling. It is not precipitated by any of the metalHc salts except lead subacetate. If a small portion of sesculin be treated with four drops of concentrated sulphuric acid, and to the sliglitly colored solution there be gradually added a solution of sodium hypochlorite, a bright violet colora- tion is obtained (Kaisy, 1SS5). ALKALOIDS. — Nitrogenous carbon- compounds capable of neutralizing acids. Contents : — Basal character ; solubilities in water, in the immiscible sol- vents, free and acidified ; extraction 1 13' solvents ; management of emulsions; filtering out ; styles of "se|iaratnr.s" ; stoppers; siphon for separators; tests of completed extraction ; tlie purity of the immiscible solvents ; liquid-extrac- tion apparatuses ; forces affecting solubilities. Precipitation by alkalies ; the scheme of Presenius ; the "general reagents" for the alkaloids, with the re- covery of the alkaloid from each — (1) iodine, (3) JMayer's solution, volumet- ric uses, (3) pliospliomolybdate, (4) bromine, (5) cadmium iodide, (6) bismuth, (7) tungsten compounds, etc., (8) tannin, (9) picric acid, (10) platinic and auric chlorides; color-reactions, with sulphuric acid alone and the several oxidizing agents, cane-sugar, etc. ; Proehde's reagent ; nitric acid ; ferric chloride, etc. Microscopic metliods ; microsublimation, and "tlie subliming cell." In their most obvious characteristics these compounds are mosilj illvisihle inlo two classes: (1) !N"on- volatile Alkaloids, com- pounds of C, H, ]Sr, ; solids, melting and subliming usually with partial decomposition when heated. (2) Volatile Alkaloids, compounds of C, PI, N ; liquids of slight vaporization at ordi- nary temperatures and high boiling points. The natural alka- ■ On the constitution of aasoulin and assculetin, Liebekmann, 1880 ; Will, 1883. ALKALOIDS. 33 loids of the first class are far nmre numerous than those of the second class. Both classes mostly inchulc bodies of decided basic power ; of an alkaline reaction restricted by sparing ae[ue(ius solubility; bases neutralizing acids in the production'of their salts, which crystalhze in cluiracteristic forms of a good degi-ee of perma- nence. In water the free alkaloids have generally little solubility, but their sulphates, nitrates, hydrochlorides, and acetates mostly dissolve with abundance in this vehicle. In alcohol the free alkaloids dissolve in must cases with moderate abundance, and their common salts almost invurialily dissolve largely. In the solvents iiiuDiscihlc wltli water — ether, chloroform, benzene, petroleum benzin, amyl alcohol, etc. — the free alkaloids differ among each other as to their solubilities, which thus be- come important meana of separation. The salts of the alka- loids are, with some important exceptions, insoluble in the sol- vents immiscible with water. Separations of alkaloids soluble in a liquid not miscible with water, from other substances soluble in the same menstruum, are, therefore, accomplished by first washing the acidulated aqueous solution to remove whatever non-alkaloidal matter is soluble in the applied menstruum, and then washing the alkaline aqueous liquid to take out the alkaloid itself.' Then, again, the non-aqueons (ethcrial) solution of the free alkaloid may be washed with acidulated water, when a salt of the alkaloid is formed and transferred to the aqueous liquid, as a step in separation. The washing of the aqueous liquid with a solvent immiscible with water, sometimes designated as the shal-iruj out., is com- monly done by agitating in a cylindi'ical stoppered vessel (Fig. 1, p. 35), and leaving the mixture at rest foi- the immiscible sol- ' This mode of using ether was proposed in 185(j by Otto, in modification of Stas's process for the reeovory of alkaloidal poisons. The plan was adopted for chloroform by Rodgers and Girdwood in hsHfi ; and for aiiiyl alcohol by U.SLAR and Erdmax.v in 1801. In 1807 Dragendorfp {Phar. Zeiisch. f. Russ- land, 6, Heft 10; Zuitsch. anal. O/uan., 7, 531; " Ermitttlung von Giften," St. Petersburg, 180^, p. 243) presented a quite comprehensive scheme of separa- tions by solvents immiscible with water, iipplieil both in acidulated and in al- kaline solutions. This scheme was traiislatrd by the author, in "Outlines of Proximate Organic Analysis" in 1875, and. more in detail, by S. Dana Hayes (Am. Chemist, 6, :t78) in 1870, The plan of separation, first published lu u, pharmaceutical journal, and primarily for the uses of the toxicologist, has been extended by chemists everywhere, so that it is now the most common mode of separation of alkaloids for any purpose, in analysis or manufacture. IMoreovcr, the way of " shaking out" by solvents immiscible with water is in frequent use for fats and acids and other bodies besides alkaloids. 34 ALKALOIDS. vent to separate in a clear layer, which is then drawn off or de- canted in some way. The solvent layer will be over the aqueous layer in the case of the ordinary solvents except chloroform, the layer of which will be under the waterj' liquid. A mixture of one volume of chloroform with three, or at the least two, volumes of ether is sometimes used as an inniiiscible solvent, lighter than water. Mixtures of alcohol (as a solvent) with ether, or chloro- form, or amyl alcohol cannot be used in " shaking out," because the water removes the alcohol fi-om the innniscible liquid. In fact, this liquid becomes water- waslied by the operation, and there are advantages in taking a water- washed ether or chloroform to begin with, so that the disturbing presence of alcohol (and pos- sibly of acids) may be avoided. It is to be borne in mind that ordinary stronger ether contains 4 or 5 per cent, of alcohol, and ordinary purified chloroform contains alcohol not exceeding 1 per cent. ; also that both these liquids are liable to contain, and to acquire, free acids. It is even possible that, in shaking out with several portions of acidulous ether, the reaction of the aque- ous liquid may be changed from alkaline to acid, and if this change be overlooked the separation may be reversed without the knowledge of the operator. The absence of free acid, therefore, is to be required of ether, chloroform, or amyl alcohol when one of these is used as a solvent upon an aqueous liquid. Washing with water, readily done by the analyst, serves to remove both alcohol and acids,' but the removal of acids is done sooner and with less waste l)y washing with alkaline water. "What is said of " water-washed " solvents by no means applies to the commercial article known as " water-washed ether," which is of low grade, containing much alcohol, a slight extent of water- washing being substituted for other more efficient means in its purification. Although the presence of alcohol somewhat lessens the sepa- rative power of the solvent, yet the addition of small quantities of alcohol is sometimes resorted to to promote the formation of a clear layer of the immiscible solvent, and (as a diluent) to resolve obstinate emulsions which now and then hinder the analyst. The various resources for preventing and destroying emulsions are named from time to time in the directions in this -work. The resolution of an emulsion into the two clear layers of the immiscible liquids concerned is always promoted by some degree of miscibility between these liquids, just as a precipitate that has some slight degree of solubility, or that crystallizes, usually sub- ' The use of water-washed solvents, as standard grades of constant compo- sition, was proposed by the author in 1875 (Pro. Am. Asso. Adv. Sci., 24, i., 114). ALKALOIDS. 35 sides the more readily to leave a clear liquid. Ether forms a layer sooner than chloroform, and benzene is liable to give more trouble in the formation of emulsions than either of the former. The operator will learn that in most cases it is better to avoid the production of an obstinate emulsion, not shaking violentlj^ enough to cause it, but, if necessary, obtaining tlie desired contact of the two liquids by a slow and prolonged reversing of the upper ami lower ends of the separator. Precautions against emulsions, and devices for their resolution, are given with the various direc- tions for separations of Atropine, Cocaine, Strychnine, and else- where in this work. Among such measures may be here enume- rated : (1 ) the application of heat enough to cause a very slight or incipient boiling of the solvent, or of the water when amyl alcohol is the solvent; (2) the introduction of small portions of the clear solvent, with or without clear water, througli a little tube, into the intermediary layer of emulsion ; (3) the addition of a small portion of the fresh solvent, then gently agitated and set aside for separation of layers, this being done eitlier with the whole liquid or with the emulsified portion of the liquid drawn off for the purpose ; (i) the dilution of the solvent with alcohol ; (5) gently jarring the separator ; (6) filtrations. The euiulsitied intermediary layer, drawn off by a siphon or pipette, or, if need be, the entire mixture, may l)e iiltered, using a double paper filter (with four thicknesses all around), and wetting the filter \\'itli the heavier of the two constituent liquids. That is, with fresh chloroform, if this be solvent ; with distilled water, if the solvent be other than chloroform. The first portion of the filtrate, or even the whole of it, may be returned through the filter, and the filter and lighter liquid remaining in it may be washed with successive small portions (or with a fine, continuous stream) of the heavier liquid. As a " separator " the author prefers one with a cylindrical body and a short, conical base, the exit- tube being of small diameter and closed with a stop- cock next to the* body. The stoppered opening at the top of the separator should be of good width. Fig. 1 represents a convenient article, to be held by a " condenser clamp." But instead of a " separator," a large test-tube, or test-glass with foot, may be used with convenience, if ])rovi(k'd as follows : The top of this cylindrical tube is fitted just like that of a wasli- bottle, with a stopper bearing a delivery-tube and blow-tube, as Fig. 1. 36 ALKALOIDS. illustrated in Fig. 2. The delivery-tube is to be narro\v_ and play up and down iu the stopper, to take off the liquid content, either the upper or lower layer, at any point. The blow-tube is so bent and long enough to enable the operator while blowing to see clearly the movement of the liquid at the inner end of the delivery-tube, when this is brought near the line. The division between layers may be carried to very near the outer end of the delivery-tube, when the remaining liquid is drawn back again. To rinse the delivery-tube the stopper is transferred to a tube containing a little of the clean solvent, which is shaken up and then blown out. To make an exact separation of the layers, a small quantity of the fresh chloroform or other solvent may be di-awn in through the delivery-tube of the apparatus last above mentioned, next to the aqueous layer, without disturbing the layers, which are thus separated from each other. In other apparatus the introduction may be through a pipette. RiiMer stoppers and tubes are acted on by ether and chloro- form, and can only be used when the liquid does not come in contact with them, and then only for a short time, as they are soon injured and swollen by the vapor of these menstrua. Good, ALKALOIDS. 37 well-pressed corks serve for brief uses without special prepara- tion; but to avoid waste of vapor in standiiijj;, and especially where the solvent is to be distilled, as described hereafter, the cork-s should he rendered Jmpervious, after being iitted, by an application of chrome-gelatine. Four parts of gelatine are dis- solved in 52 parts of boiling water, the solution filtered, and 1 part of amiuonium dichromate added. This mixture is apphed as a coating to the corks, and permanent cork connections may be completely sealed by covering the corks in place over upon the glass. After application the coating should stand two days in the light to harden. It will occur to any analyst sumetinies to make separations with immiscible solvents, as preliminary trials, or as small quali- tative or (Quantitative tests of a tentative character, when a test- tube or vial is a sufficient container, and the one liquid may be drawn off from the other with a pipette. In using a mouth f)ipette, however, it is usually better to take out the aqueous ayer, this being the less volatile li(|uid, and less liable to drip when the pipette, closed at the top, is being withdrawn. Also a simple siphon of narrow glass tubing bent in U-form may be filled with the solvent or with water, and used to draw off either layer from any container. In any case, a separation hj or from an inmiiscible solvent is of the nature of a washing, and complete removal of the dissolved body is not accomplished by a single division into the two liquid layers, or with a single portion of the solvent. Suc- cessive portions of the solvent must be applied, in repetition of the " shaking out." Especially is this true with ether, chloro- form, and amyl alcohol, which dissolve in water to some extent. From two to five washings may be i-eqiiired. In any case of doubt and of importance, positive information must be gained by a test of the last " wash-liquid," as in ordinary quantitative analy- sis, and the washings repeated until the last liquid drawn off, or the residue therefrom, gives a negative result tinder some deli- cate test for the alkaloid operateil upon. In all the cases where assay operations, by a single shaking out with (say) chloroform, have been verified by good authority as giving a correct result under a control analysis, it may be almost certainly set down that the correctness of the result lies in a happy balance of errors rather than in the clear truth. The loss of the alkaloid taken is just balanced by the gain of foreign matter which goes into the weight at the end. And if all the conditions of loss and of gain can be held constant, or nearly so, the method may give results of substantial correctness. 38 ALKALOIDS. The purity of the immiscible solvents chosen for use must be assured. Let a good portion be evaporated to dryness in a weighed beaker, and the absence of fixed residue ascertained. The residue may well be taken up with acidulated water, and the solution subjected to test by some of the " general reagents for alkaloids," or by the chief qualitative test to be used in the contemplated analysis. purified by distillation. If necessary, the solvents are to be To avoid the attenuation due to the use of repeated portions of solvent, as well as the expense of considerable quantities of the same, a plan of distillatory use of the solvent has been recently proposed, in the so-called "extraction-apparatus for liquids." This apparatus corresponds in principle to the ex- tr;icti(jn-apparatus of Tollens and others for the continuous per- ALKALOIDS. 39 eolation of solids, which have been for some years the favorite means of applying solvents to organic bodies, and is described under Plant Analysis. The immiscible solvent is distilled from its solution while it is being applied, in the apparatus of later device, to the aqueous liquid. The apparatus of 8chwakz (1884)' is shown in Fig. 3. It is connected above with a returning con- denser. The two connecting tubes serve, the one to carry vapor to the condenser, the other to conduct the overflow of condensed solvent back to the warmed reservoir— both these tubes having a mercury-joint provided for by an inclosing cup. Neumann's apparatus " will be understood from Fig. 4. A. Eiloaet (1886)' describes a simple apparatus (Fig. 5) which can be set up by any chemist with glassware at hand, including a small condenser, the small glass tubing to be bent and fitted in stoppers, as shown in the figure. The tube delivering the solvent into the aqueous liquid may be made with a funnel-end, as figured, so that perforated platinum foil may be bound over the expanded orifice, and the solvent distributed in fine streams. This apparatus, in Fig. 5, applies the hot vaporous solvent to the liquid to be ex- tracted, which is therefore maintained at near the temperature of boiling of the sol- vent. The same is true of the apparatus of jS^eumann and of Schwarz (Figs. 4, 3). For fats this heat of the aqueous mixture is needful, and for many substances, includ- ing some alkaloids, it may be desirable, but with some alkaloids it is not admissible. And Eiloart presents a modification of his apparatus in Fig. 6, whereby the solvent reaches the aqueous liquid from the con- denser, and not directly from the distilling flask ; so that, if the condenser be kept cold enough, there will be no heating of the aqueous liquid, the temperature of which may be regulated at will. All the forms of liquid-extraction apparatus so far described in publications are devised for light volatile solvents, constitut- ing the layer above the watery liquid. For cldoroforDi, received in the layer below the aqueous one, the apparatus illustrated in ^ Zeitsch. anal. Chem., 23, 368. ' 1885 : Ber. d. chem. Ges., 18, 3061. » Chem. News, 53, 381. 40 ALKALOIDS. Fig. 7 may be used, with atteation now and then, to transfer the chloroformic layer to the distilling Hask. In doing this the valve leading to the con- denser is closed, the lower valve is opened, and pressure then applied at the outer opening of the blow-tube until the chloroformic layer is siphoned over. The degree of sohthUity m the immiscible sol- vents varies with forces of adhesion and coliesion not operative in dissolving from the drj' mass. The solubility of an alkaloid, in agitating its acidulous watery solution with ether or benzene at the mo- ment the liquid is made alkaline, may be more or less abundant than the solubility of the dry alka- loid in ether or benzene.* The moment of liberation of the alkaloid from its salt is certainly the most favorable time for its free solubility. Therefore many operators, in dissolving by agitation, add first the immiscible solvent and agitate, and then add the alkali for liberation of the alkaloid, when the agi- tation is con- tinued. And it is to be borne in mind that the fac- tors of solubil- ity, reported for a certain sol vent with great minute- ness precisely as obtained by experiment at a given tem- perature, are liable to vary within liberal limits by influence of several condi- tions besides temperature. ' " Comparative Determinations of the Solubilities of Alkaloids in Crystal- line, Amorphous, and Nascent Conditions : Water-washed solvents being used." The author, 1875 : Pro. Am. Asso. Adv. Sci., 24, i. Ill ; Am. Chem., 6, 84; Jour. Chem. Soc, 29, 403. FIG.7. ALKALOIDS. 41 A common plan for separation of alkaloids l)y reascm of their diverse solubilities, brought int( > use at a very early period, re- quires no other menstruum than water, and consists in dissolvini^ out the alkaloid as a salt, by use of acidulated water, and prcci- pitathig the a/lnlo/d./rce, by adding an alkali to the clear a(iue- ous solution. In operations of this sort alkaloids have relations like those of metallic bases other than the alkalies. Like the metallic bases, alkaloids are in some instances dissolved by free fixed alkalies, or an excess of this alkali precipitant, in other in- stances dissolved 1)y an excess of ammonia, and in many cases not dissolved by excess of any alkali. An acidulous watery so- lution of cinchona bark, in the clear but colored filtrate, on add- ing solution of sixlium hydroxide to excess, presents an abun- dant precipitate of tlie mixed impure cinchona alkaloids, colored by extracted matters. Precipitation by one of the alkalies or alkali earths has a place in various processes for preparation of alkaloids from vegetable sources, and a share among the means of qualitative ami quantitative analysis. Tlius in most of the methods of the morphiometric assay of opium, ammonia is added to the a(|ueou8 solution of morphine salt, when simple trans- position occurs, as follows: ((\-I-IigN( ).,).J-I.,804-f 2^114011= aCi^Hif.XOg II„0(cryst. morphine)+(]Nn^)JS()^. In one of the preferred methods the morphine is dissohed out of the opium by an excess of lime, the resulting lime-solution being treated with ammonium chloride, when a transposition occurs, precisely corresj^onding to that of a precipitate of aluminium hy- droxide according to the eijuation : K.,A1._,< )^-|-:3XI-l4Cl-[-4HoO = Alo(0ri)g+2Iv(Jl-f 2NII4OII. And" no" more absolute separa- tion of the chief alkal(.)iil of opium than this crystalline preci- pitation (favored by tlie contact of immiscible solvents) has yet been estabhshed. The action of certain of the alkalies, used in excess, to re- dissolve the precipitates they form in solutions of alkaloid salts^ has been made available in analytical separations. Fresenius's manual of qualitative analysis has long presented a scheme of separation, or of classification, of a few common alkaloids, as follows : ( )f Non-volatile Alkaloids, (1) those which are precipitated by potassa or soda from the solutions of their salts, and redissolve readily in an excess of the precipitant (morphine) ; (2) tliose whicli are precipitated liy jiotassa or soda from the solutions of their salts, but do not re(bssolve to a, per- ceptible extent in an excess of the precipitant, and are preci]ii- tated by sodium bicarl)onate even from acid solutions (narcotiiie, quinine, cinchonine) ; (3) those which are precipitated by potassa 42 ALKALOIDS. from the solutions of their salts, and do not redissolve to a per- ceptible extent in an excess of the precipitant, but are not pre- cipitated from (even somewhat concentrated) acid solutions by the bicarbonates of the fixed alkali metals (strychnine, brucine, veratrine, atropine). The solubility of quinine, and the far more diflficult solution of the other cinchona alkaloids, in an excess of ammonia, is used in the valuable method of Kerner for separa- tion of quinine from other cinchona alkaloids, and estimating the proportions or fixing the limits of the latter. Finally, it remains to notice that, although the salts of the common mineral acids (sulphuric, hydrochloric, nitric) with the alkaloids, are soluble in water, there are certain double salts whereby nearly all alkaloids are precipitated, in somewhat com- plex compounds nearly insoluble in water. The precipitants are known as The General Reagents for Alkaloids. The most use- ful of these are (1) Iodine in solution of potassium Iodide, (2) Potassium Mercuric Iodide, (3) Phosphomolybdate, (4) Bromine in aqueous hydrobromic acid, (5) Potassium Cadmium Iodide, '(6) Potassium Bismuth Iodide, (7) Tungsten compounds, phos- phoantimonic acid, and ferric chloride with hydrochloric acid, (8) Tannic Acid, (9) Picric Acid. In applying a precipitant to a solution of an alkaloid, when it is desired to avoid expenditure of the material under examina- tion, a drop of the solution is to be treated with a drop of the reagent, on a glass slide placed over black paper. A hand- magnifier is serviceable. (1) Iodine in Potassium Iodide Solution (WAaN^n, 1866).' — A deeinormal solution of the free iodine : 13.66 grams of iodine in a liter of solution of iodide of potassium ; or, 20 grams iodine and 50 grams potassium iodide per liter (Woemley'). Applied, as it is, in acidified solution, it is in efliect iodized hydriodic acid. Brown and flocculent ' precipitates ; generally with very little solubility in water ; formed more perfectly in acidulous solutions, and in those containing a little free sul- phuric acid. Iodine tincture is a less useful form of the re- agent. The precipitates are more or less soluble in alcohol. A very slight addition of the reagent is' suflScient, and it is better not to use enough to give color to the solution. In a liquid liable to contain dissolved substances not alkaloids, the fact of precipitation is not strongly characteristic, while the absence of precipitation is conclusive for ordinary alkaloids. ' Zeitsch. anal. Chem., 4, 387. GENERAL REAGENTS. 43 On standing, the precipitates in most instances crystallize in somewhat characteristic forms, more perfectly from solutions in alcohol. In composition (Hilgee, 1869 ; Bauer, lS7i) the precipitates are addition compoimds, of different but related types. When quinine sulphate solution is treated with a little of the reagent, there is formation of CjolIo^NoO^.HI.I ; with more of the re- agent, quinine pentiodide, Qo^t^^Si,,.'^!. . I^, is formed ; and in presence of excess of alcoholic iodine and sulphuric acid, various iodosulphates are formed, as stated more fully un- der Quinine, d, -' Herapathite test." Atropine pentiodide, C^-HogXOg.HIg, obtaiucd l)v excess of the reagent, crystallizes from hot alcoholic solution, in fine blue-green, lustrous needles or plates. A corresponding tri-iodide is obtained by adding less of the iodine. Strychnine tri-iodide crystallizes from alcoholic solution in long, dark-brown prisms, of rhombic shapes, with bluish-metallic lustre. Tlirown down as an amorphous preci- pitate it is red-brown. Berberine tri-iodide, CoqII 3^7^04.1113, crystallizes from hot alcohol in li.mg, red-brown, diamond-lus- trous needles. Piperine tri-iodide, (Cj-rii,,X03)uIll3 (Joegen- SEX, isTT), crystallizes from hot alcoholic sdhition in long, steel- blue needles of metallic lustre. Recovery of the free alkaloid from the precipitates of hy- periodides may be accomplished as follows : Tlie washed pieci- pitate is dissolved in excess of aqueous sulphurous acid, and the solution evaporated on the water-bath, the sulphurous acid being kept in excess until the hydriodic acid is expelled, when the former is also driven off and the alkaloid remains as a sulphate. — The hvperiodide precipitates dissolve in solution of thiosulphate, and niay be thereby separated from various foreign matters carried down by adding free iodine to organic extracts. If the thiosulphate solution be treated with the iodine solution in ex- cess, the alkaloid is again precipitated. (2) T'otdsshnn Mercuric loiliile. M(njer''s Svlution.^ — The 'F L Wixi KLER, ISoO. A. V. Planta-Reichbnatj, " Das Verhalten der wichtigstcn Alkaloidegegeri ReagL-iitieii " (S. 41). Heidelberg, 1846. Thomas B. Gboves " On some compounds of iodide and bromide of mercury witii the alkaloid's " 1S59: Jour. Cliem. Soc, ii, !t7, 188 ; P?iar. Jour. Trans., i8, 181 ; Am Jour Plurr 36,535. Ferdinand F. Mavbb, 1862-3: Pro. ^m. P/tarm., 1862 2.38- and rin-m Xfi™. 7, 1.59; 8, 177, 189 ; A711. Jour. Phar., 35,20 ; Zeihch aval Chem. 2, 225; Jahr. r'/iem., 1863, 7(»:i. G. Draobndorff. "Werthbeslimmnng," 1874, p. 9 and elsewhere. A. B. Peescott, ■'Estima- tion of alkaloids bv potassium mercuric iodide," 1880: Am. Chem. Jour 2, 294; Jour. Chem. Soc, 42, 604 : Chem. i\>«w, 45, 114; Ber. d. Chem. Oes., 14, '1421. 44 , ALKALOIDS. solution proposed by Mayer is tlie one generally used for pur- poses qualitative or quantitative. It is a decinormal solution of i(HgCl.,+6KI) = the hydrogen equivalent of Hg. Of dry, crystallized mercuric chloride, 13.525 grams ; potassium iodide, 49.680 grams ; separately dissolved in water, and the mixed solu- tions made up to one liter. The reactions of the solution appear to correspond with the formula KIHgl3.(KI)3+2KCl,' instead of (KI).,HgI„+2KI+2KCl. Dragendorff prefers to make quan- tities, above "specified, to 2 liters instead of 1. Mayer's solution is applied only in acidulous solutions, in testing for alkaloids ; therefore ammonia does not interfere, as the precipitate of mercurammonium iodide is not formed in pre- sence of free acids. The acidulation may be with sulphuric or hydrochloric acid, and may be strong without dissolving the precipitate. The solution " tested must not be alcoholic, and must not contain acetic acid. Some organic matters other than alkaloids cause precipitates. With strychnine the precipitate is obtained in dilution of 1 to 150000 ; with quinme, in solutions of about the same dilution ; while with morphine, or with atro- pine, solutions of 1 to 4000 do not give the precipitate. The precipitates are curdy or flocculent, and for the most part of a yellowish-white color. Caffeine and theobromine are not precipitated by potassium mercuric iodide. The composition of some of the alkaloid iodomercurates varies with conditions of concentration, excess of reagent, and acidity ; while the precipitates of other alkaloids are nearly con- stant in composition. With strychnine the precipitate is not far from C2j^Ho2iSr„03llIHgl2° ; with morphine the precipitate cor- responds to a variable mixture of (C;^7lT;^g]Sr03)4(riI)4(Hgl3)3 and (Ci7H^g]Sr03)4(HI)g(Hgl2)3 ; with quinine the precipitation ap- pears to be most nearly, though not closely, represented by (C2oIT24N2C*2)2(HI)3(HgIo)3 ; and with atropine the gravimetric value of the precipitate does not correspond to its volumetric factor. In volumetric use the " end-reaction " is denoted only by the 'In the proportions lor (KI)2HgT3-l-2KCI, the mercuric iodide remains dis- solved only in concentrated or hot solution. The quantity of alkali iodide adopted by Mayer cannot be very much reduced and retain solubility at the decinormal dilution in the cold. A permanent solution with the help of bro- mide can be obtained as follows: HgCl3 + 4KT-FKBr : mercuric chloride, 13.525 ; potassium iodide, 33.13 ; potassium bromide, 5.94; water to 1000 by volume. This solution may be supposed to contain (KI)jHgl3H-KBr + 2KCl. (The author, 1880: Am. Ghem. Jour., 2, 304.) 'The author, 1880 : Am. Chem. Jour., 2, 296. GENERAL REAGENTS. 45 completed precipitatimi.' After the last addition from the bu- rette the precipitate is either allowed to subside, or a little por- tion is iiltered out and a drop of the reai^^eiit added from the bu- rette to the clear si.kition. Some of the precipitates subside readily, strong acidulation usually favoring this result ; with others much time is reipiired, and titration in this way is gene- rally slow. Filtration is the better way : using a nuu"ute filter, not over 5 mdlimeters or ^ inch in radius, held in a loo]5 of pla- tinum wire or a coil of drawn-out glass tubing, over a glass slide placed upon black paper. A drop or two is taken, with the stir- ring-rod, from the mixture containing the pi-ecipitate, iiltered through the wet filter, and treated over the black ground with a drop of the reagent from the burette, when the slightest turbid- ity can 1ie seen. Before the end of the titration all the test-p(jr- tions are drained and rinsed witli a few drops of water passed througli the niter into the mixture containing tlie precipitate. In volumetric estimation the strength of tlie alkaloidal solu- tion should usually be 1 of alkaloid to lino of solution — a second estimation being made, if need be, for this graduation. The quantity of alkaloid precipitated l)y 1 c.c, under given condi- tions of cijncentration, etc., is stated with the directions for (j^uan- titative work on the se\'eral alkaloids described in this work. A quite full list of the volumetric factors for Mayer's sohition was given by ifuyer, and some of these have been subjected to con- trol analyses l)y Dragendoi'ff and others; but the jiresentation of such a list is here intentionally avoided. It miist lie understood that flie alhihiidnl eqv'ivuh'ni of o/ie r.c. vii/y'/'fi /rtt/i the oondi- tionx, especially with that of concentration. Unless the analyst has good authority for an alkaloid equivalent, given with speci- fied conditions, he should standardize his Mayer's solution, with an alkaloid solution of known strength, for himself, holding de- grees of concentration, acidulation, mass, and time the same for the titration of the solution of unknown strength that they are for the solution of known strength of alkaloid. The end of the reaction is the point when further addition of the reagent ceases to cause a precipitate. Before this point is reached, howe^'cr, in some cases tlie addition of a drop of the solution of the alkaloid will catise a precipitate — the mixture having attained a conqiosi- tion of equilil)rium (not very rare among chemical reactions) in which precipitation is caused by a drop of eitlier the ioclomercu- rate or the alkaloid solution. AVhen tlie precautions here re- ' Trials of various indicators for the eiid-reiiction Wfi-i' reported l)y tlio author in Am. Glifm. Jour ,.2, ;!04, where also attention is called to the error of Mayer's direction to titrate back with silver nitrate. 46 ALKALOIDS. quired are observed, titration with Mayer's solution becomes a trustworthy means of estimation. The alkaloids can be obtained from their iodomercurate pre- cipitates by triturating the washed precipitate with stannous chloride solution and potassium hydroxide to strong alkaline reaction, and then exhausting with ether or chloroform or ben- zene as a solvent for the alkaloids. Strong alcohol can be used as a solvent if potassium carbonate be taken instead of potassium hydroxide. — Also, the mercury can be removed from the precipi- tates by dissolving in alcohol, adding acid if need be, treating with hydrogen sulphide gas, and filtering. The filtrate can be freed from iodine, if this be desired, after expelling the hydrogen sulphide, by adding some excess of silver nitrate solution, filter- ing, adding hydrochloric acid to the filtrate, and filtering again . (3) Phosphojudlyhdufe.^ — A fixed alkali phosphomolybdate in strong nitric acid solution — in effect a solution of jahosphomo- lybdic acid. Applicable in acidulous solutions and in absence of ammo- nium salts and free ammonia, which also precipitate it. It is prepared as follows : The yellow precipitate formed on mixing acid solutions of ammonium molybdate and sodium com- mon phosphate — the ammonium phosjjhomolybdate — is well washed, suspended in water, and heated with sodium carbonate until completely dissolved. The solution is evaporated to dry- ness, and the residue gently ignited till all ammonia is expelled, sodium being substituted for ammonium. If blackening occurs, from reduction of molybdenum, the residue is moistened with nitric acid and heated again. It is then dissolved with water and nitric acid to strcmg acidulation ; the solution being made ten parts to one of the residue. It must be kept from contact with vapor of ammonia, both during preparation and while pre- served for use. The precipitates of alkaloids, by adding this reagent to their acidified solutions, are amorphous, and of yellowish colors, some- times orange-yellow, in other cases brown-yellow. In general tliey have very little solubility, and are obtained in very dilute solutions. Besides ammonia, other bodies not alkaloids are liable to give precipitates with this i-eagent. A negative result is trust- wftrl-hy for the exclusion of more than traces of alkaloids in the solution tested. Most of the precipitates are soluble in ammonia, and those of alkaloids that are strong reducing agents mostly dis- ' SoNNENSCHEiN, 1857: Ami. Chem. Phar., 104, 45. Db Vmj: Jour, de Pharm., 26, 319. Struve, 1873: Zeitsch. anal. Chem., 12, 170. GENERAL REAGENTS. 47 solve with the blue color of reduced molybdic acid, or with some shade caused by admixture of blue. Tlae ammoniacal solution is blue with aeonitine, aniline, atropine, berberine, morphine, nicotine, and physostigmine. Alcohol and ether do not dissolve the precipitates, and acetic acid has but a slight solvent action. The alkaloids can be recovered from the precipitates by add- ing potassium or sodium hydroxide solution, and shaking out with an immiscible solvent for the alkaloid, as ether, chloK)form, benzene, or amyl alcohol. Adding potassium carbonate instead of hydroxide, strong alcohol can be added instead of an immis- cible solvent. A gravimetric value of the phosphomolybdate precipitate has been obtained for a few of the alkaloids, but it has not been ascertained what conditions are necessary to secure a constant composition.' (4) Bromine in aqueous hydrohrmnio acid. — Woemlet di- rects the use of aqueous hydrobromic acid saturated with bromine. Applicable to aqueous solutions of the salts of the allialoids, neutral or slightly acidulous with a mineral acid, and in absence of acetic acid and of alcohol, which dissolve the precipitates. Besides alkaloids, the phenols and other bodies give precipitates with bromine. (See Phenol.) The limit of precipitation of the alkaloids is at dilution to from 5000 to 100000 parts — with mor- phine, 1 to 2.500 ; with nicotine or conine, 1 to 10000 ; with aeo- nitine, codeine, or brucine, 1 to 25000 ; with strychnine, narco- tine, or veratrine, 1 to 100000 (Woemley). In general the pre- cipitates are amorphous ; with atropine, crystalline. (5) Potassium cadmium iodide (MaIrme, 1866). — Prepared by saturating a boiling concentrated solution of potassium iodide with cadmium iodide, and adding an equal volume of cold-satu- rated solution of potassium iodide. In diluted solution, precipi- tation is apt to occur. — This reagent precipitates the aqueous so- lutions of alkaloid salts, acidified by sulphuric acid, the precipi- tates being soluble in excess of the precipitant, or in alcohol. Amorphous at first, the precipitates become crystalline. — The al- kaloids can be recovered from the precipitates as directed for those formed by potassium mercuric iodide. (6) PotdxHiutn hismufJi, iodide (Deagendoeff, 1866). — Pre- pared from bismuth iodide, in tlie way directed for the lust- ' It appears probable that a dilute solution of the phosphomolybilatn, standardized by solution of an alkaloid of known strength, could be used I0 estimate the quantity of the same alkaloid under strictly parallel conditions. The end-reaction can be found as directed for Mayer's solution. 48 ALKALOIDS. named reagent. Cannot be diluted. Applicable as a precipitant to aqueous solutions of alkaloid salts, strongly acidified with sulphuric acid. (7) Metattmgstic acid, Phosphotungstic acid (Scheiblee, lyOO), Silicotungstic acid (Godeffeoy, 1876), and Phosp>ho-anti- iiwiiio acid (ScHULTZE, 1S59), have been used as general preci- pitants for the alkaloids. Godeffeoy (1S77) iises a solution of ferric chloride in hydrochloric acid as a precipitant for alkaloids. (8) Tannic acid (Beezelius, Heney, Dublanc, Hagee), in solution with 8 parts of water and 1 part of alcohol, gives whitish, grayish-white, or yellowish precipitates with nearly all the alka- loids. In the larger number of instances these pirecipitates are easily soluble in acids, frequently dissolving in excess of the tannic acid ; on the contrary, some of the alkaloids are precipitated by tannic acid only in strong acid solutions. Ammonia dissolves the taunates of the alkaloids. Dilute acetic acid dissolves the precipitates of taunates of acouitine, brucine, caffeine, colchicine, morphine, physostigmine, and veratrine ; acetic acid not dilute, the precipitate of quinine. — Gold dilute hydrochloric acid does not dissolve the precipitates of taunates of acouitine, bL-rherine, brucine (dissolves sparingly), caffeine, cinchoniiie, colchicine (dissolves slightly), narcotine, papaverine, thebaine, solanine, strychnine (dissolves slightly), veratrine. — Cold dilute sulphuric acid does not dissolve the pre- cipitates of taunates of acouitine, physostigmine, quinine, sola- nine, veratrine. — Precipitates are completely formed in solutions str(ini(lv acidulated with sulphuric acid, by aconitine, physostig- mine, and veratrine, tliough none of these alkaloids gives a full precipitate in slightly aci(hilated solution. — Alkaloids are recovered from their taunates by mixing the moist precipitate with lead oxide or carbonate, drying the mixture, and extracting with an imniiscil)]e solvent or with alcohol. (9) Picric acid, HCgIl3(N03)30 (Woemley, 1869 ; Hagee, 1869). — Used in very dilute, saturated aqueous solution, or in a sparing addition of the alcoholic solution. Applied as a preci- pitant of alkaloids in their neutral solutions, or, better, in solu- tions acidulated -with sulphuric acid. Many of the precipitates become crystalline, and give characteristic forms under the mi- cr()Pco])e ; in general they have a yellow or yellowish-white color. With morphine the precipitate is formed, in drop-tests, in solu- tion of 1 to 500 ; with aconitine, atropine, or veratrine, in solu- tion of 1 to .5000 ; with brucine or narcotine, in a solution of GENERAL REAGENTS. 49 1 to 20000 ; with strychmiie, 1 to 25000 ; with nicotine, in solution of 1 to 4000 (AVokmley).— The alkaloids can be re- covered from their picratu precipitates by uddinf,^ an alkali solu- tion and exhausting with a solvent iminiscihle with water, or by evapurating- to dryness with a solution of potassium or sodium carbonate, and extracting with alcohol.— IIagee has used preci- pitation with picrate in some estimations of alkaloids. For cinchona alkaloids,' 10 grams of the powdered bark, covered with 130 c.c. water, witli 20 drops of caustic potassa solution of s.g. 1.3, are digested at boiling temperature and stirred for a quarter of an hour. Of dilute sulphuric acid, s.g. 1.115, 15 frams are added, and the mixture boiled 15 to 20 minutes. Hien cold the whole is made up, by the addition of water, to 110 c.c. ("the volume of 110 grams of water"). The mixture is filtered, through a paper filter of 10.5 to 11.0 centimeters (8^ inches) diameter, into a graduated jar, and the volume of the filtrate (about 60 c.c.) noted. To this fihrate (100 c.c. of which represents the 10 grams of bark) picric acid solution saturated in the cold is added, in quantity about 50 c.c, or enough to complete the precipitation (as ascertained by aHowing a few drops to fiow down the side of the vessel). After half an hour the precipitate is gathered on a weighed filter, washed, and dried between blotting-papers over the water-bath. The dried preci- pitate of picrates of cinchona alkaloids cnntains (according to Hager) two molecules of picric acid as anhydride, 440 parts, to one molecule of cinchona alkaloid, 308 to 324 parts, without water of crystallization. Or 8.24 parts of the precipitate indi- cate about 3.5 of mixed cinchona alkaloids. Then the noted number of c.c. of decoction taken : lOt) : ; the indicated quan- tity of mixed alkaloids in the precipitate : * =: quantity mixed alkaloids in the 10 grams of bark. (10) Phdinir C'fiJoride. Auric CliJor'ide. — Solutions of these salts, hardly to be classed as special reagents for alkaloids, yet give precipitates with the greater number of them. Platinic chloride is often required in establishing distinctions between alkaloids, as noted in this work under the qualitative reactions of the respective compounds. The same may be said of auric chloride. The melting points of the alkaloidal compounds of these metals serve as constants useful for identification, esjiccially in distinguishing the derivatives of alkaloidal I'adicals. The composition of these metallic precipitates has in most cases been '1869 : Phar. Centralh., p. 145 ; Zeitsch. anal. Chem., 8, 477. so ALKALOIDS. estimated from the percentages, respectively, of metallic platinum and metallic gold, left after ignition. These percentages were much depended upon in the earlier years of the chemistry of the alkaloids, and are given full and prominent statements in Gme- lin's Hand-book of Chemistry. — The platinum precipitates are divisible into those which do and those which do not dissolve in hydrochloric acid — cinchonine and quinine, morphine, and strychnine lieing placed among those not readily soluble in this acid. — The platinum precipitates have a yellow or yellowish color. The gold precipitates of a number of the alkaloids blacken by reduction on standing. Color-reactions of the AlJcaloids. — In general it should be borne in mind that color-reactions are subject to variation (1) by impurities of the alkaloidal material, (2) by impiirities of the reagent, and (3) by conditions of concentration, mass prej^onde- rance, temperature, and time. Also, that the best authority to guide the operator is the result of a control-test upon a known portion of the alkaloid in question, holding all conditions to be the same. Conceii-traf eil S'i>?j)/n/rie Afir/ ' dvo'p-ped upon the dry alka- loid, on a white porcelain surface or on glass over a white ground, without heating, reacts as follows : colorless with atro- pine, caffeine, chelidonine, cinchonidine, cinchonine, codeine, hyoscino, hyoscyamine, morj^hine, nicotine, pilocarpine, quini- dine, quinine, staphisagrine, strychnine, theobromine. Of these, on warming, a purplish to brown color is given by moi'phine. Yellotoish colors are gi\'en by colchicine, gnoscopine, and jer- vine ; m/d/s/t. colo/'s a.ve i^iven (either at once or after a short time) hj apomorpliine, brucine (pale rose), conine (pale), gelse- minine, meconidinc, narceine (to black), narcotine (yellow-red to violet and blue), ncpaline, physostigmine, rhocadine, sabadilline, , sabatriiiG, solanine, taxine, thebaine, veratrine, and veratroidine ; il>t/s/i, ro/ or s iwe given ]>y crvptopiiie, curarine (on standing), and papaverine ; and greeiiisli colors \)\ beberine, berberine, emetine (brown to greenj, piperine, pseudomorphine, and rhoeadine. — Of glucosiiles, rcdilish colors (^mostly bright) are given by amygda- lin, colombin, cubebin, elaterin, hesperidin, phloridzin, populin, salicin, sarsaparillin, senagin, smilacin, syringin, tannic acids. ' Traces of nitric acid, not infrequent as an impurity in " C. P. sulphuric acid," cause a great difference in the reaction with morphine and other alka- loids colored by nitric acid. See the composition of " Erdmann's reagent," given in the foot-note under Nitric Acid Color Tests. On the Reactions of Alkaloids with Sulphuric Acid, cold, warm, and hot — alone, with nitric acid, and with permanganate — see Gut, 1861-2: Phar. Jour. Trans , [2], 2, 558, 063 ; 3, 11, 113 ; Zeitsch. anal. Chem., i, 90. GENERAL REAGENTS. 51 Froelide's liett/iii/'io acid containing iniiJyhdio acid.' — A solution of 0.001 grain of molybdic acid or alkali molybdate, in 1 cc. of concentrated sulphuric acid (Dra- gendorff), freshly prepared by the aid of heat, and used when cold. Froehdb took 0.005 gram of the molybdate to 1 c.c. of sulphuric acid, and Buck[N(iham took as jnuch as 1 i)art of molybdate to 15 of the sulphuric acid ; but the more uttenuatud proportion of the molybdate (1 to 1840) gives the more dis tinctive reactions. — The reduction of niol)'bdic acid to hydrated molybdic molybdate is attended with a bright blue color. This reduction occurs in concentrated sulphuric acid, by heat alone, at the temperature of incipient vaporization of the sulphuric acid. Xunierous inorganic and organic reducing agents cause the reduction and give the color to mol>'bdate. As a chai'acter- izing reaction it is applied mostly to alkaloids, when non-alka- loidal matter must be excluded, and the more dilute solution (jf molyli(late is the more trustworthy. Froehde's reagent gives no color with atro])ine, caffeine, cin- chonidine, cinchonine, conine, delphinine, hyoscinc, hydscya- mine, nicotine, strychnine, theobromine ; i/clloirisli cii'oj-x with aconitiiie, colchicine, piperine ; red(Ht; Arii. .Tonr PAkc, 45, 170. OrAci-.x- DORFF, 1873: '• Bciiiii;,'!! zur },'ciicht. ('Iictii. organ. Giftc" A. B. Prcsrolt, 1871): " Froehde's Kriijjeiil us a Test fur Mor|iliiiie,'Mm. Jy"c. Pliar.. 48, .lit; Jnin- der Pharm., 187(i, 502. On various reactions nt the bluo oxide of iiiolyb- ileiium, seeMASCUKB, 1873. 52 ALKALOIDS. with aconitine (yellow to brown or red, variable), codeine (orange-yelluw), morphine (yellow to red), narceine, nareotiiie, papaperine (orange), piperine (orange), rlioeadine, sabadilline (yellow), thebaine, \-eratrine. Red colors are obtained by aconi- tine (red-brown, variable), aponiorpjiine, berberine (red brown), brucine (blood-red), papaverine (orange-red), pseudomorphine (orange red), physostigmine. A Mue color is given by colchi- cine and by solanine (Drageudorff). Some ghicosides give bright colui's ; ligustrin and syringin, blue tints. SdliLniric (ichl {cowci^niY-dXcd)^ follo'inei! hy a niiimfe addi- tion of nitric acid (s.g. 1.40-1.4L'), or of solid potassium nitrate." No color is, given by atropine, caffeine, cinchouidine, ciuchonine, nicotine, pilocarpine, (piinidine, quinine, stapliysagrine, strych- nine, theobromine, lied colors are given liy brucine, curarine, narcotine (red-violet), nepaline, physostigmiue, sabadilline, the- baine, veratriue (gradually, cherry-red). A violet color is given by morphine (under directions specified for that alkaloid). Co- deine gives a succes>ion nf culdi's, as also does colchicine. Sidjdntric Acid and Cane Sugar.'' — The substance to be tested, in the dry state, is mixed with (i to 8 i)arts of cane-sugar, and a few nulligrams of the mixture are placed upon a drop or two of concentrated sulphuric acid, over a white ground. The gradual browning of tbe sugar itself is disregarded, and will be covered by the bright colors of characteristic reactions. Wo colors are given by atropine, brucine, caffeine, cinchonidine, ciii- chonine, conine, nicotine, C]uinidine, Cjuinine, strychnine, and theobromine. Rcddixh colors are given by codeine, curarine, gelseminine, morphine (pnrple-red, then blue-violet, dark blue- green, and lastly blackish-yellow — limit 0.0001 to 0.00001 gram), nepaline (gradually), sabadilline (red dish- violet). Kliluish color by veratrine. — Various oils, and albuminoids, give bright colors with sulphuric acid and sugar. Hydrochloric Acid, concentrated, gives colors with only a few alkaloids. lieddisJi colors are given by physostigmine, sabadilline, and veratrine. ' Eedmann, 186] : Ann. Pharm. Cliem.. I20; Zeitsch. anal. Ghem., i, 234. Erdmaim mixed six drops of nitric acid of s.g. 1.25 with 100 c.c. of water, and added ten drops of this mixture to 20 grams of sulphuric acid. Of this — " Erdmann's reagent " — 8 to 20 drops were added to 1 or 2 milligrams of the solid to ))e tested, and the color noted after ^ to -J hour. — Husemann, 1863: Ann. Cliem. PJiar., 128, 303 — Ihe well-known test for morphine. Dbagen- DORPF, 1868: "Rrniittelung von Oiften," p. 239. ^ ScHNEiiiKR, 1S72: Ann. Phys. Chem. Pogg., 147, 128; Zeil'ich. anal. Chem., 12, 2iy. Respecting reactions with substances not alkaloids, ScHULTZE, Ann. Cliem. P/iar., 71, 266. MICROSCOPICAL CHARACTERISTICS. 53 Other lieaijcntsfov aUcalouh as a class, or for groups of alka- loids. — Iodine in liydriodic acid, gold bromide, sodium gold thiosulphate, jiotussium gold iodide, lead tetra-cliloride, and manganese perhydroxide in sulphuric acid, were reported upon by F. Skliii in 1ST7. Perchloric acid, Feauhk, 1KT!J-1880. Sodium arseniate with sulphuric acid, Taiteesall, 1«79. Cu- pric ammonium hydrate, N"adlee, IsTi. Ferric chloride and sulphuric acid, llow, 1S7S. Fused antimonious chloride, Smith, IJiTlt. Nitroferricyauide of sodium, as a precipitant, HoESLEY, 1802. The Ilivroscojjical Chariicteristics of alkaloids, in their various combinations, recei\e attention to some extent in all chemical literature upon these bodies, and in the description of the several alkaloids in this work. Among the special contri- butions are the following: IIklwio, 18(15: "Das Microscop in Toxicologic."' GoDEFFEOY and Ledeemann, 1877 : oncincliona alkaloids. Woemley, 1SS5 : " Microchemistry of Poisons," 2d ed., Philadelphia. A. Percy Siirrn, 1880 : identification of alka- loids by crystallization under the raicroscojje, Analyst, 11, 81. On 2[icrosriNimation of All'aloids : Helwig, 1861: Zcitsch. anal. Chem., 3, 13; "Das Microscop in Toxicologic," 1865. Guy, 1867 : Phew. Jour-. Tnins., [2], 8, 718 ; 9, 10, 68, 106,195, 370; "'Forensic Medicine." London, 1875. Stoddaet, 1867. Ellwood, l8t!8. Blyth, 1878 : Joiw. Chem. Soe., 33, 313. In this work, see under Caffeine. — The Subliming Cell of Dr. Guy, improved by Blyth, consists essentially of a ring of glass, about \ inch in thickness, or from 1 to f inch. This glass ring rests on an ordinary " cover-glass " — a thin disc used under this name in microscopy. Another cover-glass is placed upon the ring, which is of a diameter, to fit the Cdver-glasses, and with them make a closed cell. The ring can be made of a section of glass tubing by grinding the edges. The cell, so constituted, was heated by Dr. Guy through a brass plate on which it rested. Dr. Elyth prefers to rest the cell upon li(|uid metal, using mercury for tem- peratures below about 100° C'., and fusible metal for tempera- tures above this point. The liquid metal is contained in a porcelain capsule of about 3 inclies diameter, supported on the ring of a retort-stand, and heated directly by the flame. A flask of suitable size, from which the Ixittom has been removed, is placed over the capsule, upon the ring of the retort-stand, and made to carry the thermometer, held in a perforated stopper and with its bulb immersed in the liquid metal by the side of the subliming cell. — A minute speck of the article tested is placed 54 A LOINS. on the lower disc of the cell. Blyth's definition of a sublimate is this : " The most minute films, dots, or crystals, which can be observed bj a quarter-inch power, and which are obtained by keeping the subliming cell at a definite temperature for sixty seconds." ALOINS. — Varieties of a neutral crystalline principle ob- tained from the several kinds of aloes. As first described (T. & H. Smith, 1851), it was obtained from Barbadoes aloes, and was the body now named barbaloin. There have been described : Barbaloin Aloes. Barbadoes YieU.^ 30-35 per cent., at most, TiLDEN, 1873. SOMMARUGA and Eqger, 1874. C17H20O7 Nataloin Socaloin IN'atal Socotrine Zanzibar 16-35 percent., at most, 'i per cent, average, Plense, 1885. C„H,sO, CisHieOr TiLDEN ascribes to barbaloin the formula 03^11330^^4.1120, and to nataloin C33H2gO^;L ; and Flockigee (1871) obtained for socaloin 03411330^^5. 5HgO. Aloins are identified by their color-reactions with nitric and sulphuric acids, by which, also, and by production of chrysammic acid, they are distinguished from each other id). Aloes is found in mixtures by treatment with acids, or by extraction with amyl alcohol and treatment with various reagents (d, p. 55). Ohrysammic Acid, p. 56. As to physiological effects, with reference to valuations, 5, p. 55. a.—Barljolo'in, crystaUized from a concentrated aqueous solution of Barbadoes aloes, appears in tufts of small yellow prisms, losing 2.69 per cent, of water by drying at 100° 0. or in vacuum. Nataloin exists in a crystalline state in JSTatal aloes, from M'hich it is left on treating with an equal portion of alcohol at 48° 0. or under, and when recrystallized forms thin, brittle, rectangular scales with some of their angles truncated. It loses no water at 100° 0. Socaloin exists in Socotrine or Zanzibar aloes in prisms of good size ; when recrystallized from methyl alcohol, tufted acicular prisms, which may be obtained 2 to 3 millimeters long. At 100° 0. it loses about 12 per cent, of water. h. — Aloins are without odor and have the taste of aloes. Their purgative power has been questioned, and while they have ' Of 18 varieties of aloes, yields of from 3.2 to 31.3 per cent, were ob- tained: Dragexdorff, 1874: " Werthbestimmung." A LOINS. 55 had some little medicinal use as therapeutic representatives of aloes, more in Great Britain than elsewhere, yet this use has not extended, although aloin is more agreeable for administration than the aloes from which it is extracted. Deagendobff states (1874 : " Werthbestimmung "), on experimental data, that (1) the resins of any variety of aloes, separated as insoluble in cold water, in doses of 0.35 gram (5 to 6 grains), prove inactive ; (2) that perfectly pure aloins, in doses of 0.3 to 0.5 gram (5 to 7 grains), prove inactive with many persons ; and (3) that the so- called aloes-bitter, soluble in cold water and containing either amorphous aloin or oxidized products, represents the activity of the drug ; also (4) that the purgative power of an aloes is measured by the quantity of bromaloin precipitated from an aqueous solution of the drug, also by the quantity of precipi- tate by tannic acid. Dragendorff infers that aloin is converted into bodies having the purgative action of aloes. Tilden (1876) found that all three aloins are decidedly uncertain and variable in their action, and seem to present no advantage over an equal dose of aloes, except perhaps that griping was rather less com- mon under their use. c. — The aloins are soluble in water, barbaloin the most freely of the three, socaloin in about 90 parts, and nataloin very spar- ingly. Alcohol dissolves all the aloins, socaloin requiring about 30 parts, and nataloin about 60 parts (230 parts absolute alcohol). In ether aloins are but slightly soluble, though socaloin dissolves in about 380 parts. Aloin "from the different varieties of aloes " is described in Br. Ph. (1885) as " sparingly soluble in cold water, more so in cold rectified spirit, freely soluble in the hot fluids. Insoluble in ether." d. — Nitric acid (s.g. near 1.40 or 1.42), applied to the dry aloin on a porcelain slab, gives a bright red color with harbaloin or nataloin, not with socaloin. The crimson red of barbaloin fades quickly ; the blood red of nataloin does not fade unless heated (Histed, 1871 ; Tilden, 1876). BoiUng with nitric acid produces chrysammic acid, (i\J:l^(^0^fi2 (tetranitrodioxyan- thraquinone), of intense red color, from both barbaloin and nataloin, not from socaloin. Oxalic and picric acids, in addition, are obtained from harlaloin by action of boiling nitric acid (distinction from socaloin or nataloin). If nataloin be wet with concentrated sulphuric acid, and then touched by the vapor of strong nitric acid from a glass rod or by a minute fragment of potassium nitrate, a fine blue color is obtained (distinction from barbaloin or socaloin). Concentrated sulphuric acid, applied to 56 AMYGDALIN. the dry substance, and followed by a minute fragment of potas- sium dichromate (as in the fading- purple test for strychnine), causes a green or greenish-purple color, changing to greenish- yellow. — Alkalies cause the decomposition of aloins. Solu- tions of aloes, too, lose their bitterness and their purgative power when made alkaline (G. McDonald, 1885). Cheysamjiic Acid (see above) crystallizes in gold-glittering needles, or in yellow fern-leaves resembling picric acid. It de- tonates on heating. It is acidulous in reaction, and of intensely bitter taste. It is insoluble in cold water, easily soluble in alco- hol and in ether. It forms colored salts with metallic lustre. Potassium chrysammate crystallizes with bright green lustre, or (from acid solutions) as bright crimson needles with a slight golden reflection. Aloes. If a grain of aloes or dry mixture be dissolved in 16 drops of strong sulphuric acid, 4 drops of nitric acid (s.g. 1.42) added, and the mixture diluted with one ounce of water, a deep orange or crimson color will be obtained. On adding ammonia the color changes to a claret. All substances containing cliry- sammic acid behave nearly the same in this test, except that they turn pink on adding ammonia directly to their aqueous solutions, while the solutions of aloes do not (Cripps and Dt- MOND, ISSo). — If a fluid containing aloes be extracted with amy I alcohol, the residue left by evaporating this solvent will have a bitter taste, and when this residue is dissolved in water the solu- tion will give precipitates with bromine in potassium bromide solution, basic lead acetate, mercurous nitrate, and tannic acid, and will reduce gold chloride and Fehling's solution. The dry residue will give a blood-red color with potassium cyanide and hydroxide (Deaoendoeff, Lenz, 1882). AMYGDALIN. CoHa^l^On = 45Y (Liebig and Wohler, 1837). Ci2Hi404.(OH)7.CvHe.CN (Schiff, 1870).— A gluco- side which occurs m the bitter almonds and in numerous other plants which yield hydrocyanic acid by natural fermentation. The bitter almonds, after removal of the oil by pressure, are di- gested twice with hot 95$^ alcohol, and allowed to stand for some time. The alcohol is decanted and concentrated to a syrup, from which the amygdalin is precipitated by ether. The precipitated amygdalin is washed with ether and recrystallized from boiling alcohol. Amygdalin crystallizes from alcohol in colorless scales anhy- drous or with 2II2O, from water in transparent prisms, becoming opaque in the air, and containing SHgO. It becomes anhydrous ARBUTIN. 57 at 110-120° C. It is odorless, of a slightly bitter taste and neutral reaction, and rotates the plane of polarization to the left. It is soluble in any proportion of hot and 12 pai-ts cold water ; in 11 parts boiling and 901 parts cold alcohol (s. g. 0.S19) ; in 12 parts boihng and IIS parts cold alcohol (s. g. 0.939) ; insoluble in ether. Concentrated sulphuric acid dissdlvus it with violet-red color, which turns black on warming. The other mineral aeiils decompose it. In contact with einuhin and water (10 parts amygdalin, 1 part emulsin, and 100 parts water) it is changed into benzoic aldehyde (oil of bitter almonds), hydrocya- nic acid, and glucose, as follows : CooH.,,XOii+2II„0=07HgO+HCN+Ci3lIoiOi3. Through farther change of the hydrocyanic acid, formic acid also is formed. By boiling with dilute sulphuric acid the same reaction takes place, when formic acid is always formed. 17 parts of anhydrous amygdalin, or about 21 to 25 parts (theoretical- ly, 19 parts) of the ordinary commercial amygdalin, yield, when fermented with emulsin, one part hydrocyanic acid and 8 parts bitter- almond oil. Boiling amygdalin with aqueous alkalies or baryta changes it to ammonia and amygdaltc acid (CgoHgeOig)- ANALYSIS, ELEMENTARY. See Elementary An- alysis. ANALYSIS OF PLANTS. See Plant Analysis. ANALYSIS, ORGANIC. See Oeganic Analysis. ARBUTIN. CioHigO^ = 272.— A ghicoside found (about 3.5^) in the leaves of the bearberry {Arctostaphylos Uva-ursi) and in a number of other plants, especially in those belonging to the order Ericaceaj. It may be obtained by precipitating the decoction with lead subacetate, freeing the filtrate from lead by hydric sulphide, treating with animal charcoal, and crystallizing. Crystallizes in bunches of silky needles which have the com- position (Cj^IIjgOy)^ . H3O. They become anhydrous at 1< 10° C. and melt at 170°, have a bitter taste and neutral reaction. Sparingly soluble in cold water, readily soluble in hot water and in alcohol ; slightly soluble in ether. Boiled with dilute sulphuric acid, or subjected to the action of ennilsin or another ferment contained in the bearberry, it is converted into hijiJro- quinone, CgllgOg, and glucose. Treated with manganese diox- ide and sulphuric acid, it is oxidized U) quiiione, GqH^O.^, aiid formic acid. It does not reduce alkaline cupric solution, and is S8 A SPA RA GIN—BEBIRINE . not precipitated by salts of the metals. Concentrated sulphuric acid dissolves it without color. Nitric acid turns it black, gradu- ally dissolving it to a yellow solution. If an aqueous solution be rendered alkaline with ammonia and then phosphomolybdic acid added, it becomes blue [one part in 140,000 parts water gives a distinct color — Jungmann, 1871 : Am. Jour. Phar., 43, 205]. ARICINE. See Cinchona Alkaloids. ASPARAGIN. C4H8N303=132.— Amido-succinamic Acid. Exists already formed iu asparagus {Asparagits officinalis) and a great many other plants. It ci-ystallizes from the cold-water ex- tract of asparagus upon concentration to a thin syrup, and may be purified by treatment with animal charcoal and recrystalliza- tion from hot water. The crystals are hard, brittle, transparent prisms of the tri- metric system having the composition C^HglSTgOa . HoO. They are odorless, have a slight, disagreeable taste, are permanent in the air, and become anhydrous at 100° C, above which temperature they are decomposed. Asparagin is soluble in 58 parts cold and 4.4 parts boiling water ; in 500 parts cold and 40 parts boiling 60^ alcohol ; in 700 parts boiling 98^ alcohol ; insoluble in abso- lute alcohol, chloroform, ether, and benzene; easily soluble in acids and aqueous alkalies. It forms weak compounds with both acids and alkalies. In contact with the accompanying extractive substances, yeast or casein, etc., it is changed by fermentation into succinate of ammonium (sometimes with the intervening formation of aspartate of ammonium). When boiled with acids or alkalies it is resolved into aspartio acid (C4ll7]Sr04) or amido- succinic acid, and ammonia. Respecting the quantitative estimation of asparagin, see the current reports of E. Schulze, 1881 to 1885. ATROPINE. See Mideiatic Alkaloids. BAKING POWDERS. See Taetaeic Acid. BEBIRINE. Bilerine, CigHoiNOg, dried at 100° C— In Greenhart or Bibirin bark (Eritish Guiana), H. Rodie, 1835 ; as '■'■Buxine" in bark of Buxus sempivirens or Common Box, Faury, 1830, identified with bebirine by Walz in 1860 and Fluckiger in 1869 ; as Peloshi, in Pareira Brava root (Chon- drodendron tomentosum and Cissampelos Pareira), Wiggers, 1839, identified with bebirine by Fliickiger in 1869. BENZOIC ACID. 59 a— A white, amorplious powder, melting at aLoat 145° C, and decuinposiug at a higher temperature. Its salts of common acids are uncrybtallizable, pulverulent or resinous, and white or yellowish-white. h. — The alkaloid and its common salts are odorless, with a strong and persistent bitter taste. Its etiect is held to resemble that of quinine, and is given in about the same quantities. ."?•— ^ery slightly soluble in water (6600 parts cold, 1.500 boiling); soluble in 5 parts absolute alcohol and 13 parts of ether ; soluble in chloroform, benzene, amyl alcohol, and carbon disul- phide. Its solutions are strongly alkaline to test-papers. The sulphate, hydrochloride, and acetate are readily soluble in water ; the solutions having a neutral reaction. d. — The alkali hydrates and carbonates give precipitates, soluble in excess of the hydrates. Precijntates are caused by potassium mercuric iodide (white), pntassiimi iodide, mercuric chloride, gold chloride (yellow-white), platiiiic chloride (pale yel- low), and sodium phosphomolybdate (dissolved blue l)y ammo- nia, decolored by boiling), jiicric acid (vellow). sulphocyanate (reddish-white). Nitric acid dilute and juitd.wiinn nitrnte give a vjhite precijjitate (YliickiireT); sodium phos])liate, a white precipitate. The pure alkaloid does not reduce iodic arid. e. — Bebirine has been prepared from the different plants in which it occurs, by extraction with acidulated water, and precipi- tation with soda or ammonia, with a precipitate by lead subacetate and extracticm therefrom liy dilute sulphuric acid (or by digesting the precipitate witli magnesia and extracting with alcohol or ether). Purification by animal charcoal is sometimes used instead of, or after, the lead precipitation ; theoljject in either operation being chiefly removal of resinous matter. f. — The precipitated alkaloid loses 8.2 p. c. water (near- ly HIIoO) at 1 00° C— Bebirine platinic chloride (riJI„;LN03)., (■HCl)oPtCl4(Bodeke)-).— TheHvdrocldorideisC\8Tl.,iN03.IlCL —The" Sulphate (CiJLiNOgjJIoSO^ [IMaclagen]. BENZOIC ACID. Benzoesiiure. Acide Benzoique. C7TIgO.,=122 (monobasic). C,.Jig.COjl. Carboxyl-benzene. Without isomers. — Sain'Oftt : — licnzoic acid is found, uncom- bined, in the proportion oi 10 to 11» per cent., in Benzoin, the balsamic resin of Styrax Benzoin, produced in Siaiu and Suma- tra ; also in smaller proportions in Balsam of Peru, in Balsam of 6o BENZOIC ACID. Tolii ? (Bussy, 1876), in fruit of Vacciniiim vitis-idsea (cowberry)' (O. Low, 1S79), and in the Xantliorrhoea resins. It has been found in certain plums and other fruits. In combination with ethereal bases, forming essential oils, it is found in numerous bal- sams and resins, and in the oils of cinnamon, bergamot, origa- num, and eananga (ylang-ylang). The fragrant oil slightly per- vading the Benzoin is reported to be ethyl benzoate. The benzoates frequently accompany or substitute the compounds of cinnamic acid, and sometimes occur with cqumarin. The suint of sheep's wool contains benzoates (Tayloe, 1876). Benzoic acid is slowly formed by the atmospheric oxidation of oil of bitter almond (benzoic aldehyde), appears among the oxidation-products of cinnamic acid and various aromatic compounds, and results from certain decompositions of albuminoids. Schulze • (1885) finds benzoic acid in the heavier (phenol-containing) coal-tar oils. Hippuric acid, in decomposing urine, may change to benzoic acid. Benzoic acid is manufactured (1) from Benzoin, either, as "flowers of benzoin," by direct sublimation,' or in the wet way, as "crystallized benzoic acid," by dissolving with lime, precipi- tating from the calcium benzoate solution by adding hydrochloric acid, and recrystallizing from hot water to remove resin. (2) From the Hippuric acid of graminivorous animals, chiefly horses and cows, by concentrating the urine, acidulating with hydro- chloric acid to obtain crystallized hippuric acid, and boiling the latter -with crude hydrochloric acid, when benzoic acid and the by-product glycocoll are promptly formed : CH., . NH(CO . CgHg) . COoH+H„0 ^CeHgCOgH+CH^ . NHg . COgll (3) From the coal-tar product, Naphthalene, Cj^gHg, which by treatment with nitric acid is converted into phthalic acid, CgH4(C02li)2, when the latter, heated to about 350° C. with its equivalent of calcium hydrate, in absence of air, forms the lime salt of benzoic acid : 2CeH4(CO„)3Ca+Ca(OH)„=(CgH5C02)2Ca+2CaC03. And (4) from Toluene, of the coal-tar distillates, CgHg.CHg, known as toluol, by formation of trichloro-toluenes (Cgllg.CClg), and conversion of the latter to benzoic acid. The pharmaco- poeias require the " natural benzoic acid." Of " artificial benzoic ■ LoEWB, 1869, and Rump, 1878, maintain that part of the benzoic acid obtained is not ready formed in the benzoin, but requires to be separated from some combination, or union with another acid. The combination with cinna- mic acid, 2C7H8OJ . CsHbOj, has been reported. BENZOIC ACID. 6i acid " the production from toluol is increasing, and little is made from phthalic acid. (See, further, under Impurities.) Bkxzoic acid may he 'Klentijicd hy its hehavior in suhlima- tion (a), toward ,sol\ents and preeipitants (c), in reduction to bit- ter-almond oil, and in its reaction with ferric salts {sely estimated volinitetricaRtj with a standard solution of alkali (Bockman : '• rntersuchu'ngsmetlioden." l^^Sl), using litmus as the indicator. The weighed material for estimation is ti'eated directly with an excess of the volumetric alkali measured from the burette, stirred to bring all the lienzoic acid into solution as benzoate, when the liquid IS titrated back with the proper volumetric acid. Each c.c. of normal solution of alkali (after deducting c.c. of normal solution of acid) = 0.122 gram of benzoic acid. Taking 1.22 gram of the material, each c.c. of decinormal solution of alkali (after deducting for the acid used in titrating l)ack)=l per cent, of benzoic acid. Benzoic acid may be weighed, directly, as C-TIiiC).,. For this purpose the be^t form is that of good crystals, either from a so- lution or bv slow sublimation. The residue obtained liy spon- taneous evaporation, of chloroform, ether, or other separative solvent of free benzoic acid— also a clean preci]Mtate— may be weighed. The acid is to be dried over sulphuric acid, any excess of liquid or adhering moisture being first taken up with Ijlotting- paper. 66 BENZOIC ACID. Salts of benzoic acid are usually treated to obtain the free acid, as above described (e), but they may be precipitated, in a neutral solution, by lead acetate, as stated under d. The lead benzoate, Pb(C7H 503)2, is washed with cold alcohol acidulated with one- half per cent, of acetic acid, and dried at 100° C. The weight multiplied by 0.5416 gives the quantity of benzoic acid. g. — Impurities. — Chemically pure benzoic acid is precisely the same in all properties, whether manufactured from the bal- samic benzoin or from urine, toluol, or naphthalene ; but a chemically pure acid has not been manufactured, on a commer- cial scale, from any source. The chief uses of benzoic acid are (1) in medicine and (2) in the production of dyes. It is used, also, for the manufacture of food flavors a.nd as an antiseptic. For medicinal purposes the pharmacopceias designate its source as follows : Ph. Germ. — " From benzoin by sublimation . . . yellowish to yellowish-brown . . . with odor of benzoin, somewhat empy- reumatic." Br. Ph. — " From benzoin ... by sublimation. ISTot chemi- cally pure. ISTearly colorless." Ph. Fran. — " From benzoin " prepared by alternative direc- tions (1) hy sublimation, (2) by humid method. U. S. Ph. — White scales or needles, " having a slight aroma- tic odor of benzoin." There may be two reasons for requiring medicinal benzoic acid to be sublimed from " the gum " : (1) the essential oil of benzoin obtained with the sublimed acid has a stimulant effect and an agreeable odor ; (2) by outlawing the artificial product the injurious impurities frequently present in it may be avoided. The artificial acid, quoted as " German benzoic acid," has been for several years priced at from one-third to two-thirds the value of the natural acid, quoted as "English benzoic acid." Un- doubtedly chemically pure benzoic acid will be made from hip- puric acid or from toluol (Dymond, 1883 ; Jacobsen, 1881), and furnished at prices lower than those for the natural acid. But hitherto, in any production of the artificial acid for medicinal uses, with little encouragement for open statement, there has been more effort to counterfeit the chemical impurities of the natural sublimed acid than to avoid the chemical impurities of the arti- ficial product. A chemically pure benzoic acid, from any source, is acceptable for the preparation of medicinal benzoates. In sensible properties the acid recently sublimed from ben- BENZOIC ACID. . 67 zoin has a white or pearl color if suhliined slowly, at tempera- ture of about 125°-140° C, with rejection of the last fraction of sublimate, even this, from some varieties of benzoin, being nearly colorless. But a sharp heat, of about 200° C, gives a yellowish sublimate, becoming yellowish-brown in its last por- tions, and in proportion to increase of color is the distinctness of empyreumatic odor obtained, in addition to the proper ethereal and vanilla-lilie odor of tlie benzoin obtained with colorless sub- limates. The acid sublimed from Sumatra or Penang benzoin has only a faint odor, not vanilla-like. Any empyreumatic oil pervading the crystals darkens gradually by action of air, and colorless samples of sublimed benzoic acid are liable to ac(|uire a yellowish tint on long keeping. Benzoic acid well prepared in the wet way (p. 60) is in water-white crystals, larger and not so much in flocculent masses as the " flowers of benzoin." It has but a slight ethereal odor of benzoin, without empyreuma. But if it has not been crystallized from the precipitate it will contain much resin of benzoin, with some color, and will not dissolve clear in hot water. — Artificial benzoic acid is frequently obtained in distinct prismatic crystals of considerable size. That from liippuric acid is apt to have a horse-stable odor ; that from to- luol, an odor of bitter-almond oil ; and imitated " flowers of benzoin " nuiy have ethereal or empyreumatic odors. Cinnaraic acid is occasionally present in all varieties of ben- zoin. In sublimation it requires a higher heat than benzoic acid, and its vapors are denser. Sublimed benzoic acid with empyreu- matic odor and yellowish-brown color is likely to contain cinna- mic acid, if it were present in the benzoin. Benzoic acid from benzoin by the wet way is by no means likely to be free from cinnamic acid, if this were present in the benzoin. The impurities incidental to sources may be enumerated as follows : In natural benzoic acid by sublimation : Ethereal oil containing more or less styrol (cinnamene, Cf^IIg), vanillin (CgHgOg) if prepared from the true Siamese benzoin (Jannasch and Bu^tp, ls7S), and sometimes empyreumatic distillate. Also cinnamic acid. — In natural benzoic acid by the wet , way : Cin- namic acid, resins, calcium chloride, ethereal oil. — In the j)roduct from hippuric acid : Ammonia or nitrogenous bodies readily yielding it, substances giving the odor of urine or of the perspi- ration of the horse, hydrocyanic acid (a prochict of hippuric acid by heat), and clilorides. — In toliiol-benzoic acid: Chloro- toluenes, oil of bitter almond (benzoic aldehyde)— which is formed from dichloro- toluene, while benzoic acid results from tricldoi'o- toluene — ammonium compounds, chlorides and sulphates. 68 BENZOIC ACID. Imitated natural Leuzoic acid is jDrepared by subliming from a mixture of (odorless) artificial benzoic acid, and either benzoin or the resinous residue after sublimation of the natural acid. Also, by addition of ethereal oils, etc. Testa. — Far cinnwtiuc acid, by its oxidation, giving benzoic aldehyde, with odor of bitter-almond oil. One gram of the acid (itself free from almond odor) with half as much permanganate of potassium, rubbed in a mortar with a fe-w drops of water (U. S. Ph.) A mixture of the acid with equal quantity of the permanganate and ten parts of wafer is warmed for a short time in a test-tube (Ph. Germ.) The test is dehcate and sufiieieut, but the decoloration of a permanganate solution has no meaning in the quest for cinnamii^ acid. — Fo7' the etliereal and einj[jyreu- matic oils peculiar to natural benzoic acid by sublimation (chemi- cal impurities in evidence of medicinal genuineness), their reac- tions as reducing agents upon permanganate, or upon silver in alkaline solution, are resorted to, as follows : Of the saturated water solution, when cold, lU c.c. are treated ^vith about 10 drops of solution of potassium permanganate (1 to 1000). "With the true sublin:ed acid the color changes to red-brown and brown in from I to 2 minutes ; with natural benzoic acid by precipitation and crystallization the color changes in 4 to 8 minutes ; with various samples of artificial acid treated to imitate the natural sublimate, over 2 minutes (Ilagers Commentwr , 2d ed., 59).' — Boil 0.1 gram of the acid Math 3 c.c. of water of ammonia ; add about 5 drops of silver nitrate solution, and then drops of diluted hydrochloric acid until a permanent and decided turbidity is just reached (while there is still a very slight excess of ammonia). With true sublimed benzoic acid the slight precipitate is not white, but yellowish. — Concentrated sulphuric acid, M-ith a smaller quantity of the benzoic acid, gives a yellowish color with the sublimed acid, becoming brown at 150"^ C. ; while at this high temperature the chemically pure acid remains coloi'less, and traces of hippuric acid give a, brown to black color. — For am- monium or other nitrogenous co'inpounds accompanying an acid made from the urine, dissolve in a wide test-tube with a little alcohol and fixed alkali to strong alkaline reaction, heating to near l)oiling, and testing the vapor with moistened red litmus-pa- per and by the odor, for ammonia. — For chlorides and sulphates, ' Hager severely criticises the Ph. Germ, direction to give 8 hours for this reaction. Upon this and other tests of genuineness of natural benzoic acid, see Lenken, 1882; Schaer, 1882; Sohneidee, 1882; Sohickih, 1882; Schaoht, 1881; Jaoobsbn, 1881 ; Bymond, 1883. CINNAMIC ACID. 69 test tlie saturated aqninius sohition with silver nitrate solution, and barium cldoride solution. Fur clihiro-loluiiics, slowly lieat a portion under solid potassium or sodium hydrate (free from chloride) on platinum foil, dissulve the mass in water, filter if neeessary, aeididate with nitric acid, and test with silver nitrate solution. Or apply the blow-pipe test for chlorine, with the copper bead, as directed by the L^ S. Ph. — For Jujipurui acitl^ and (j/'i>ss (i/'ijK/iic itates are not mark- edly characteristic, that with iron resembling benzoate (*/). It is separated by methods used for benzoic acid, and from the latter with some difRculty {e). Estimated gravimetrically as free acid 70 CINNAMIC ACID. (f). Its natural combinations, and sources of production, are described in g. a. — Cinnamic acid is a colorless solid, crystallizing (from vapor or solution) in monoclinic prisms or plates. Specific gra- vity (at mean temperature, water at 4° C. as 1.) 1.247 (Schecedkk, 1879). It melts at 133° C. (271.4° F.) (Millek, 1S77 ; Tiemann and Heezfeld, 1877). It boils at 300° to 304° C. (572°-679° F.) (E. Kopp, 1849), suffering partial decomposition unless heated gradually, the products containing cinnaniene (CgHg), stilbene, carbon dioxide, etc. It vaporizes much below its boiling point. i. — Without odor, and of an aromatic, slightly sharp taste. The vapors are pungent and excite coughing. — In doses of 5 to 6 grams (80 to 90 grains) it causes a just perceptible irritation of the throat. After its administration the urine contains cinnamic acid with hippuric acid, the latter probably preceded by oxida- tion to benzoic acid (Eedmanx and Maechand, 1842). G. — Very sparingly soluble in cold water, moderately soluble in boiling water, freely soluble in alcohol, soluble in ether. With litmus and other indicators it shows an acid reaction. The me- tallic cinnamates are monobasic, stable salts. Those of the alkali metals are soluble in water ; of alkaline-earth metals more soluble in hot w^ater ; most others little soluble in water. Aqueous solu- tions of alkali cinnamates, on adding an acid, give a precipitate of cinnamic acid. By dry distillation they yield, among other pro- ducts, benzaldehyde. Ethyl cinnamate boils at 266° C, is of specific gravity 1.3, nearly insoluble in water, soluble in alcohol and in ether. Methyl cinnamate has a specific gravity of 1.106, boils at 241° C, and is insoluble in water. Keaut a,n'd Meeling (1881) mention a compound of cinnamic acid with hydrochloric acid. d. — Oxidized with permanganate of potassium, or with dichromate of potassium and sulphuric acid, cinnamic acid yields benzaldehyde, or bitter-almond oil, recognized by its odor. The solid material may be treated with half as much solid perman- ganate, rubbing with a little water in a mortar. Or the solu- tion may be charged with permanganate solution, and warmed. Cells . CH . CH . C02H-|-40 = CeH5 . COH + 2CO2+ H^O. The oxidation may continue to the conversion of the benzaldehyde into benzoic acid. — Ferric salts with solutions of cinnamates give a yellow precipitate of ferric cinnamate ; manganous salts with excess of cinnamates, a white precipitate (none with ben- zoates) ; lead acetate, a precipitate of lead cinnamate ; and silver BERBERINE. yi nitrate, a stable white precipitate of normal silver cinnamate. The barium and calcium precipitates dissolve in hot water. e. — Aqueous solutions of free cinnamic acid can be concen- trated, and the residue can be dried on the water-bath, without loss of more than traces of the acid. Sublimation cannot be em- ployed, under ordinary conditions, without waste by decomposi- tion. Precipitation of cinnamic acid, in cold and not dilute solutions of cinuamates, by adding hydrochloric acid, serves well for separation. The free acid may be dissolved from a(jueons ■or dry mixtures by repeated portions of ether. — Benzoic and salicylic acids are liable, if present, to appear in separates with ciunamic acid. Among solid sublimable acids may be further named succinic and gallic acids, but these are soluble in water. As to separation of cinnamic from benzoic acid, see the latter (tf, 7, etc.) f. — Cinnamic acid may be weighed, as CgHgOg. For this purpose it may be prepared in crystals from alcohol or hot water, or in residue from ether, or in precipitate from cold concentrated solution. g, — The appearance of cinnamic acid in analysis raises the question of its production, or liberation, by the operations of the analysis, from an ethereal salt of cinnamic acid, or from its alde- hyde, or alcohol. Cinnamein, benzyl cinnamate, making a large part of Peru balsam and a small part of tolu balsam, is liquid at ordinary temperature, neutral in reaction, of sp. gr. 1.098 at 14° C, boiling with some decomposition at 340°-350° C, not soluble in water, soluble in alcohol, ether, or carbon disulphide. Styracin, cinnamyl cinnamate, is fonhd in storax, crystallizing in needles or four-sided prisms, of sp. gr. 1.085 at 16° C, melting at .38° to 44° C, and distilling with steam at 180° C. without de- composition. It is insoluble in water, soluble in hot alcohol and in ether. Both cinnamein and styracin are easily saponified by digestion with fixed alkali or alkali carbonate, when the aqueous solution, by acidulation with hydrochloric acid, yields cinnamic acid. The stvrone of storax and Peru balsam is cin- namic alcohol (CgHg.CIi.CH.COHg); and the cinnamene or styrol, of storax, is the related hydrocarbon, Cgllg . CH . CHg. The union of benzoic acid with cinnamic acid, (C7Hg02)3C9H802, melts at 95° C. BENZOYL-ECGONINE. See Cooa Alkaloids. BERBERINE. C2oHi7N04=335.— The yellow alkaloid of 72 BERBERINE. Hydrastis canadensis, species of Berberis and Ooptis, and other plants. As a hydrochloride, often commercially named hy- drastine.^ Found as follows : In Hydrastis canadensis, Kanunculacese, 1.3 to 1.8 per cent. (Lloyd). '' Coptis trifoliata, 4^ (Perrins). " " teeta (India), S..5r;, (Pekeins). " Xanthoriza apifolia. " Eerljeris vulgaris, Berberidaceee, 12^ (Perrins). " " aquifolium. " " aristata. " Jeflersouia dipliylla. " Caulophylnm thalictroides (Husemann's Pii.) " Jateorrliiza culumlia (calumba root), Menispermacege. " Miuispermuni cauadense. " Coscinium fenestratum (Ceylon calnmba wood). " Gcelocline polycarpa, Anonacese. " Xanthoxylura clava Herculis, Rutacese. In several of these sources berberine is accompanied with a colorless alkaloid. Its chemical relation to hydrastine is men- tioned in the description of the latter. Berberine responds to the general tests for alkaloids {d), among whicli it is at once distinguished bj^ its color and by the crystalline precipitations of its hydrochloride and nitrate {d). These precipitations, as well as its abundant solubility as a free alkaloid in hot water, serve to separate it from otlier alkaloids. Its separation from its vegetable sources is outlined, with refe- rences, under e. It is estimated as free alkaloid or crystalline salt, graviraetrically ; by Mayer's solution, volumetrically. a. — In brown-red pencils, grouped in irregularly radiate clus- ters ; also in branched, curved, and pointed prolongations ; some- times appearing orange-red to yellow. In amorphous and ob- ' As first found in different plants, this alkaloid was named as follows: In GefEraya inermis, bai'k, by Huttensohmid, in 1824, as jnmaicine. " Xanchoxylum clava H., by Chevallier and P., in 1826, as xanthopicrite. " Hydrastis canadensis, by Raflnesque, in \'i!&?i,3.s hydrastine. " Berberis vulgaris, by Buchner and H., in 1830, as berberine. " We . . . think it unfortunate that, since the name Hydrastis was ac- cepted by botanists, it was not followed by chemists in the naming of its pro- minent constituent, the yellow alkaloid ": J. U. and C. G. Lloyd, in " Drugs and Medicines of North America," 1884, p. 98. — An early paper on this alkaloid was that of J. D. Perrins, 1862: Jour. Ohem. Soc, 15, 339. BERBERINE. 73 scurely crystalline forms it is yellow. At 120° {). it melts to a red-brown resinous mass. As crystallized from water, it loses 19.2tl,'-i water at about 100° C. (Fleitmann), indicatiiiii; about 5II„() of crystal-water in air-dry crystals. — Tiiu hydrocliloride, C.joH^^NOjlIOl.'illoO, forms lari^^u, lustrous, p,-i)ly the murexoin test {//), and the form in which it crystallizes under the microscope (a). It shares its most distinctive tests with Theobromine, from which it differs greatly in solubilities. It is i M. V7IEGAND, rw ■* , CANTHARIDIN. ' 83 diate coloration. Caffeine should be colorless, should dissolve in 10 to 15 times its weight of boiling water, the solution remain- ing clear when diluted to 80 or 100 times its weight and cooled, and being neutral to test-papers. Respecting presence of theo- bromine, see under the latter. CAFFETANNIN. • See Tannins. CANTHARIDIN. CioHi204=196.— The highly poison ous, vesicating principle of the Spanish Fly {Lytta ■ivfticuftifin), which contains about OA^L It is also found in a great many other coleopterous insects. The powdered insects, after being moistened with acetic acid, are exhausted with chlorofonn or ether ; the extract evaporated to dryness ; the residue boiled with carbon disulphide (to remove fat), evaporated to dryness with a little caustic alkali, washed with chloroform, acidified, and agi- tated with chloroform, from which the cantharidin cryf-tallizes on concentration. It may be purified by recrystallizing from alco- holic chloroform or from acetic ether. Cantharidin crystallizes in colorless prisms of the dimetric system or in laminae, which become soft at 210° V. and melt and sublime at 218° C. 'it sublimes, in part, at ]S(i° ('., but vola- tilizes at a much lower temperature togetlier witli the vapor of water, alcohol, etc. It is soluble in bodii parts cold and ;!S(> parts boihng water (more readily when just liberated by acids); in about 3500 parts cold and readily in hot alcohol ; in !tlO parts ether; 84 parts chloroform; 500 parts benzene; KitW! parts carbon disulphide. It is soluble in volatile and fat oils ; very easily in aqueous alkalies. It is extracted from acid solutions by benzene, ether, chloroform, and amyl alcohol. Putassium hydrate solution extracts it completely from its solution in chlo- roform ; and by tliis means it is easily purified. Cantharidin acts as a weak acid', forming salts which are (especially the combina- tions with the fixed alkahes) easily soluble in water, anS), and from sour oranges of Florida and bergamot oranges of southern Europe, no interfer- ing acids l)eing present in these sources.' Cranberries contain over 2 per cent., with no other acid ;* unripe gooseberries, 1 per cent. ; and the red currant, about 1.3 per cent.' Used chiefly in ' .Timr. Ghem. Sue, 1877, i. 477. ' " Werthbestimmung," p. 103. ^ Warm gton {Jour. Clu-m. Soc, xxviii. 0:57) found in lemon-juioe, lime- juice, and bergamot-jiiice formic and acetic acids, and some non- volatile acid giving soluble calcium salt. ' L. W. Moody and tlie author : Am. Jour. Phar., 50 (1878), 566. ' ' Ilager's "Pharmacputische Praxis," I., 53., with directions for manufac- ture. For lists of filants containing citric acid see Hager's " Untorsiichung^n," II. 109 ; Husomann's " Pflanzenstoffe," 555 ; Gmelin-Kraut's " Handbuch," v. 827. SiLVESTRi, 1869: Jour, de Phar. et de Chim. [4], x. 305, reports 1 to \y, per cent, citric acid in Gyphomandra betacea, Mexico and South America. 86 CITRIC ACID. articles of food and medicine, but also to some extent to inten- sify certain colors and to remove mordants in dyeing. Citric acid is characterized by its crystallization [a) ; by its reactions with calcium and lead salts, its barium salt in well- marked crystals, and a color reaction with ammonia (d\ also by the limits of its reducing power [d). From Tartaric acid it is distinguished by its crystallization, its failure to give caramel odor when heated (Tartaric acid, a), and its weaker reducing power with chromate, etc. (<^), and is well separated by not pre- cipitating with potassium (Tartaric acid,^/"). From ordinary fruit acids it is approximately separated, by treatment of lime salts, in the scheme given under Malic acid, e. Other separations are noted at e, p. 88. Estimation, by volumetric alkali, and from weiglit of bariiim precipitate (/', p. 88) ; in fruit juices, by direc- tions under Tartaric acid. Commercial forms and impurities are noted at g, p. 89. a. — Citric acid crystallizes, from water solutions in the cold, as CgHgO^ . HgOr^aiO, and this is the hydration of the acid of commerce.' In very moist air tlie crystals deliquesce slightly ; at temperatures from 38° to 50° C. they eftioresce, and then at 100° C. become anhydrous ; but exposed at once to heat of 100° C. the crystals melt. From boiling and saturated solution anhydrous crystals are obtained. The hydrated crystals are large, water-clear, right rhombic (trimetric) prisms. — At about 175° C. citric acid decomposes, giving off pungent vapors, containing Acetone, while Aeonitic acid (soluble in ether) is formed in the residue and then decomposed (CgHgOy^CgHgOg-l-HgO). h. — Citric acid is soluble in its weight of water at com- mon temperature, and in half its weight of boiling water ; in about its own weight of ninety per cent, alcohol ; insoluble in absolute ether or chloroform,' and but slightly soluble in phar- macopoeial stronger ether or chloroform. Its water solution is inactive to the plane of polarized light. Standing in water solution it decomposes, and then gives misleading reactions of reduction. c. — Citric acid, tribasic, forms normal salts, acid salts of one- third and two-thirds basal hydrogen, and basic double salts. The alkali metal salts are freely soluble in water; iron, zinc, and cop- ' 8.57 per cent, of water. Warington (Jour. Chem. Soc, xxviii. [1875], 927) found 8.73 per cent, as ttie mean of 17 representatives, with 8.46 per cent, and 9.35 per cent, as extreme ranges. * Soluble ill 44 parts ether, at 15° C. — Bourgoin: Zeitsch. an. Ghemie, 17 (1878), 503, from Bull. Soc. Chim. Paris. 2g, 242. CITRIC ACID. 87 per normal citrates moderately soluble ; otlier non-alkali normal citrates mostly insoluble. Calcium citrate is somewhat soluble in cold, nearly insoluble in hot water. Citrate precipitates dis- solve in citric and other acids by formation of soluble acid citrates ; and dissolve in alkali hydrate solutions by forming basic double salts, such as the " soluble " citrate of iron and ammonium of pharmacy. Citric acid prevents the alkali preci- pitation of most heavy metals, the soluble double salts being formed. Indeed, numerous precipitations are prevented or hin- dered by presence of alkali citrates,' including most carbonates, phosphates (not ammonio magnesium), oxalates, sulphates, lead and barium chromates, ferric ferrocyanide, lead iodide and bro- mide, and arsenious sulphide. On the contrary, zinc and mag- nesium hydrates, lead sulphide, and most silver precipitates are not affected by citrates. Barium sulphate is precipitated in pre- sence of citrates only on boiling. Equal basal proportions of citrate and of the precipitates most favor their solutioii, which seems to be due to the formation of double salts. — Alkali citrates are sparingly soluble in hot alcohol, less soluble in cold alcohol. d. — Solution of lime, added to solution of citric acid to alka- line reaction or to citrates, causes no precipitate in the cold (dis- tinction from Tartaric, Racemic, Oxalic acids) ; but on boihng a slight precipitate is formed (distinction from Malic acid). Solu- tion of chloride of calcium does not precipitate solution of free citric acid even on boiling, nor citrates in the cold, but precipi- tates citrates (neutralized citric acid) when the mixture is boiled. The precipitate, Q-A.j^^^r^r^ . 2II3O, is insoluble in cold solution of potassa (which should be not very dilute and nearly free from carbonate), but soluble in solution of cupric chloride (two means of distinction from Tartaric acid) ; also soluble in cold solution of chloride of ammonium and readily soluble in acetic acid. — Solution of lead acetate precipitates irom solutions of neutral citrates, and from even very dilute alc(jholic solution of citric acid, the white citrate of lead, Y\{Q}^\-()~).y\\l.,('>, somewhat soluble in free citric acid, soluble in nitric acid, in solutions of all the alkaline citrates and of cliloride and nitrate of ammonium, soluble in ammonia (formation of basic ammonium lead citrate). {Malate of lead is not soluble in malate of ammonium). — The precipitation with barium is given in d. But if now the solution, with excess of barium acetate (and a little free acetic acid — Feesenius), be heated about two hours on the water-bath, the '.T Spillbr: Jour. Chem. Soc, 10, 110; Phar. Jour. Trans., [3] 17, 383; Jahr. der Chemie, 1«57, 569. 88 CITRIC ACID. barium citrate, as Ba3(CgHg07)2.3]H20, crystallizes in clino- rhombic prisms (Kammerer '). A color-test for citric acid is made by heating with ex- cess of ammonia- water — as 5 grams of the acid to 30 c.c. am- monia-water — in a sealed tube, at 120° C, for six hours.' On exposure to the air and light in an evaporating-dish the solution turns blue, slowly changing to green and becoming colorless. Usually small crystals form in the heated tube and afterward dis- appear. At 150° C the solution turns green in the tube, but at 160° C the reaction is not obtained. Tartaric, oxalic, and malic acids do not interfere. The least (quantity of citric acid revealed by the test is 0.010 gram. Nitrate of silver precipitates from neutral solutions of ci- trates white normal citrate of silver, not blackened by boiling (distinction from Tartrate). — Solution of permanganate of po- tassium is scarcely at all affected by free citric acid in the cold. With free alkah the solution turns green slowly in the cold, readily when boiled, without precipitation of brown binoxide of manganese till after a long time (distinction from Tartrate). — Dichromate of potassium solution is not reduced by citric acid (distinction from Malic, etc.) e. — Citric acid is separated from acids making soluble lead salts, through precipitation with lead acetate and subsequent treatment with hydrogen sulphide. From tannins and gallic acid, as noted under Grallotannin. Insoluble citrates are con- verted to alkali citrates, as noted under gravimetric estimation, below. f. — The acldunetry of citric acid, with litmus as an indicator, can be accurately done only by standardizing the alkali solution with weighed pure crystallized citric acid, using the same litmus- paper and holding the same conditions both in standardizing and in the estimation.^ Warington states that the litmus color " changes in a perfectly gradual manner," that " the amount of allvali used is a little less than that required by theory to form trisodic citrate," and " the more delicate the litmus-paper the nearer does the experiment approach " a neutral reaction for the normal salt. But with phenol-phthaleiii as an indicator sharp results are obtained, the end reaction being exactly at formation ' Zeitsch. anal. Chemie, 8, 298, with oats oX the crystals. ' Sabanin and Laskowsky: Zeitsch. anal. Chemie, 17(1878), 73; Jour. Chem. Soc, 1878, Abs., 342. The reaction was declared earlier in a Russian Dissertation by Sarandinaki, and in Ber. d. chem. Ges., 5(1872), 1100. 3 Waringtc?*: Jour. Chem. Soc, 28 (1875), 929, 927. CITRIC ACID. 89 of KgCgTTjOy, or tlie (.'orrespoinling sodiujii salt.' In i)r()dnction of tliis normal salt each c.c. (if a normal alkali solutidii rcpi-escnts O.OTn gram rrvstallizcd, or ().()(!4 of anhydrous acid. For ijrdoiiiii'tric v.tti nuttlon the precipitation most appro\cd is that of barium citrate, to he weighed as sulphate.'' It is most complete in solution of alcohol of (i.',»()S sj)ecitic gravity. J'l-e- viously the citric acitl is ohtained as alkali citrate; if tree, hy neutralization with soda; if combined with a non-alkali base, hy warm digestion with an excess of sodium hydroxide oi- potassium hydroxide, tiltering and wasliing — the filtrate being neutralized by acetic acid. In either case the carefully neutralized and not very dilute solution is treated with a slight excess of exactly neutral solution of acetate of barium, and a volnnic of SLO per cent, alcohol, equal to twice that of the whole mixture, is added. The precipitate is washeil on the filter with 63 percent, alcohol, and dried at a moderate heat. The citrate of barium contains a variable (|uantity of water, and is transformed into sulphate of barium by transferring to a porcelain ca])snle, burning the filter, and heating with sulphuric aciil several tunes till the weight is constant. 3BaS0^ : ^HaCglJsO^.HoO:: 1 : 0.601. Eager di- rects that barium or calcium citrate (washed with alcoh(jl) be dried at 120° to 1.50° and weighed. Ba3(CeHg07)o : SlIaCglV'^.H^O:: 1 : 0.53232. For estimation in Fruit Juices see Tartaric acid,/' (AVaring- ton, Fleischer). g. — In commerce the first form of citric acid is concentrated lemon-juice, lime-juice, and bergamot-juice, sometimes contain- ing alcohol added for preservation, and liable to contain formic and acetic acids from decomposition. Crude calcium an' mag- nesium citrates are made for transportation. In the citric acid manufacture normal calcium citrate is juvcipitated, and this is transposed with dilute sulphuric acid. Among ivijivritien tar- taric acid is the Tiiost frequent adulteration, being sometimes substituted altogether in some medicinal preparations, especially in dry "citrate of magnesia." I^ead may be present from manu- facture or storage, and calcium salt and traces of sulphuric acid may be left from manufacture. — The detection of Tartaric acid may be done by its jvitassium precijiitation, applied as described under that acid at d, or by its reduction of dichromate in the way specified under Tartaric acid, il. Phosphoric acid is said to Ik^ ' Thomson, 1883: Chsm. News, 47, 135; Jour. C/iem. Soc, 44, 830. 'J. Creuse: American Chemist, i (1871), 424; Zeitsch. anal. (Viemi,-. n (1872), 446. 90 CINCHONA ALKALOIDS. sometimes present in tlie citric acid of comnierce (Baefoed). It is most clearly detected after calcining the alkali salt. CHAIRAMIDINE and CHAIRAMINE, CHINOI- DINE, CHINOLINE. See Cinchona Alkaloids. CHRYSAMMIC ACID. See Aloins. CINCHAMIDINE. See Cinchona Alkaloids. CINCHONA ALKALOIDS.— Alkaloids of the bark of species of Cinchona and certain allied genera of the cinchoneae. In the leaf and wood in very small quantities ; most abundant in the Icirk of the root. Contents: — List of alkaloids, with description of those not used ; the com- mercial alkaloids ; the amorphous alkaloids and ehinoidine ; yield of the total and several alkaloids indifferent barks; chemical constitution; tabular com- parison of characteristics ; enumeration of means of analytical distinction ; mi- cro-chemical distinctions; separation and estimation of total alkaloids, (l)the plan of ProUius, (2) by extraction apparatus, (3) by amyl alcohol, Squibb's process, the Br. Ph. process, (4) by etliyl alcohol, the U. S. Ph. process ; sepa- ration of the alkaloids from each other, enumeration of methods; quinine sepa- ration as sulphate in detail ; separation by ether, Liebig's plan ; by ammonia, Kerner's plan; cinchonidine separation, as tartrate, with subsequent removal of quinine; De Vrij's process; Muter's method; rotatory power of the alkaloids, in methods of estimation. — Quinine, analytical outline ; (a) crystals and heat- reactions of the alkaloid and its salts : (i) taste and physiological effects ; (c) solubilities of the alkaloid and its salts; {d} qualitative tests and their limits; (e) separations in general, from pills; (/) quantitative methods, gravimetric, volumetric, in herapathite ; (g) tests for impurities ; Kerner's quantitative method; the pharmaeopoeial tests of V. S., Germ., Fran.; ammonia test of salts other than sulphate, and of the free alkaloid and bisulphate ; test of ef&o- resced salts; Hesse's test; history of Liebig's test; Br. Ph. tests; water of crys- tallization of sulphate. — Quinidine, nomenclature, analytical outline; (a) crys- tals and heat-reactions; (c) solubilities; (d) qualitative tests; (e) separations; (/) quantitative work; (gf) tests of purity. — Cincho7ndine, analytical outline; (a) crystals and heat-reactions ; (b) effects ; (c) solubilities ; (d) qu'alital ive tests ; (e) separation; (/) estimation; (g) tests of purity. — Cinchonvne, analytical out- line; (a) crystals and heat-reactions; (r) solubilities; (d) qualitative tests; (e) separations; (/) estimations; ig) tests of purity. — Quinolive., production; {a) forms and heat-reactions; (b) effects; (c) solubilities; (d) qualitative tests; tests for impurities. — Kairines. constitution and produclion, description and means of identification. — TJinUine, constitution, description. — Antipyrine, con- stitution, description, tests, and impurities. (Crystallizable alkaloids in italic ; amorphous alkaloids in Roman.) Quinine, CoqUo^X.^O.^. Pelletier and Caventou, 1820. See p. 125. ~ - ~ " Quividi7ie,Q,o(^L,'^:fi2- VonHeijningen, 1849. {Conchinine oi Hesse.) See p. 154. CINCHONA ALKALOIDS. 91 Cinchonine, Cj^gHooN'oO.' Pelletier and Caventou, 1820. See Index. Cinchonidiiw, C^gllwNoO.' Henry and Delondre, 1833 ; Winckler, 184:4';"' IIesse. Diquinicine, <^^4o^^46-'^4*-^3- Hesse, 1878. Diconchinine. Apo- diquinidine. The chief amorphous alkaloid existing in barks and found in chinoidine of commerce (p. 94). Fluo- resces in sulphuric acid solution ; gives the tlialleioquin reaction ; rotates to the right ; forms only amorphous salts ; and does not yield quinicine. Its relation to quinine or qui- nidine is shown by the equation : 2C^Qir.j^Xo02 — HgO =040^46^403: Dicinchonicine. Hesse, 1878. Dichonchonine. Apo-dicincho- nine. Derived from cinchonidine and cinchonine ; found in chinoidine of commerce ; probably existing in amorphous condition in the bark ; has not been completely isolated. (CggH^oN^O?) See Amorphous Alkaloids of Cinchona, p. 94. [Quinicine, CooHo4XoO^,. Pasteur, 1853; Howaed, 1872; Hesse, 1878. Formed by melting sulphates or other salts of quinine or quinidine. Also liy action of liglit. jSTot found in cinchona barks. Not fluorescent. Gives the tlial- leioquin reaction. Rotates feebly to the right. Amorphous, but can give rise to certain crystalline salts.] [Cinchonicine, Cj^9Ho2N„8 ; Howard, 1872 ; Hesse, 187^. Formed by melting sulpluites or other salts of cinchonine or cinchonidine. IN'ot contained in cinchona barks. Rotates to the right. Amorphous, but forms some crystalline salts.] Hydroquinine, CooHoeNyOg. Hesse, 1882. Fluoresces. Gives thalleioquin reaction. Rotates to the left. Hydroquiuidine, CgoHoeNoOa. Hesse, 1882 ; Foest and Boh- RixGER, 1882. Accompanies the quinidine of commerce. Also formed by action of permanganate on quinidine. Ro- tates to the left. Fluoresces. Gives the thalleioquin reac- tion. Hydrocinchoriidlne, Cigl^.^XoO. Hesse, 1882. Found in com- mercial cinchonidine (when this is not in loose needles). Rotates to the left. Not fluorescent. The pure base melts below 100° C. Heated with acids it becomes amorphous. iSkbaup, 1877; Laurent, 1848. The formula CjoHj.NjO, which has been long accepted, is from Reonaiilt, anil supportod liy Illasiwetz, 1851. Skraup: Chem. CtMtr., 1877, 629; Liebig's Annalen, 197, 220. 92 CINCHONA ALKALOIDS. In the bark of Kvinijid Purdieann and R. pedunculata {0. cujnva).' Quliumiine, Cj^gHo^NgOo. (Found in other barks, though most ahundant in "cuj^rea" bark.) Dextrorotatory. Hesse, ISTi!, l'S77; OuDEiiAjjs, 1879. With sulphuric acid and a trace of nitric acid, colors orange to red. Con<2uiuamine, C^iglloj^NoOo. Quiniduiiiine. Acconipaniesqui- namine. Hesse, Oudkmaxs, ISSl. Quinamidine and Quinamicine, auiorplunis isomers of quinamine. Ilovwijuiiiine. In " cuprea bai-k.'' A cuinpound of Cu2Jreine, Cj^gllooNgOo, aiid quinine, into which two alkaloids it splits and from which it may be synthesized. Levorotatory. Paul and CowNLEY, 1S81, 1885 ;' Hesse, 1885." CinchoRaiiii)i<\ Cj^gHg^XgO. Arnai'd, 1881, 1885; Hesse, ISsf) ; Ske and Kochefontaine, 1885. Dextrorotatory. Colored reddish-yellow by sulphuric, yellow by nitric acid. IVith nitrates forms characteristic insoluble crystals ; hence proposed as a test for nitrates {Phar. Jour. Trans., [3], 15, 772). (Jf a strong toxic effect. Cuscouine, CogHogXgiJ^. Hesse, 1877, in barks shipped from Cusco, in Peru. Difficult of crystallization. Kotates to the left. Accompanies Aricine. Concu.^cuninf, C^3H2g]Sro04. Hesse, 1883. Dextrorotatory. With sulphuric acid gives a green color. Free alkaloid is tasteless. Chcdramine, CooHogXoO^. Hesse, 1884. Dextrorotatory. Conc/iai/'am/'iie. f 'n.^HggNoO*- Hksse, 1884. Dextrorotatory. Chairamidine, CoolLjeNgO^. PIesse, 1884. Amorphous. Dex- ti'orotatory. Conchaivatnidine, CooHogNgO^. Hesse, 1884. Levorotatory. Turns green with sulphuric acid. In otJicr liarlcs. Paytine, C^xH^^JSToO. In 1870, from a white Cinchona bark from Payta. Levorotatory. With chlorinated lime gives a dark red color. See, further, Wulfseeeg, 1880.' Aricine, C03H28N0O4. Hesse, 1870. Pelletiee and Cobiol, in 1829, in a bark from Arica. Foimd by FIesse, in 1882, in ''cuprea" bark. Levorotatory. Not bitter, astringent taste {IIusemann''s "Pflanzenstoffe"). ' Hesse's summary : Jour. Chem. Soc, 1885, Abs., 64. 'Phar. Jour. Trails., [3], 15, 221, 401. Liebig's Annalen, 230, 55. *Phar. Jour. 3'ra»5.,[3], 11, 369. CINCHONA ALKALOIDS. 93 Pai-icine, C\gTTj^X„(). WinekliT, 1S45. In bark from Para. Fluokiuer, 1S7(>. Clnchot'tne^ C\gIIo4NoO. The U yd rochichgN.jO. Accompanies cinchonidine. Levo- rotatorv. Rksse, 18S1. Tlie existence of Honiocinchonidine (Hesse, ls77) is denied hy Skeaup (ISS(i). Hesse's Hydroconijuinine is helieved by Foest and Boh kixger to be identical with hydr( xipiinidine. TIesse (18'S5) reports that the substance previously (1883) named by him as Concnsconidine jm-dvcs to be a mixture (if alkaloids. Paytamine is an amorphous alkaloid accompanyiii<;' Paytine. Of le alkaloids of the cinchonas. All the crystallizable alkaloids in use imder pharmacopceial authority are carried under these four n:imes In elementary constituents, cincliDnino and cinchonidine have each one atom of oxygen less in the Tnolecule, aud, according to recent determina- tions, have eneli 011., less in the molecule than (|uinine and qui- nidine : C'.,.,II.,^N,0.,— r!,pII.„_,N.,Or=riT._,+0. To a liTnitcd extent other crystallizable iilkaloids of ciTichona are certainlv carried into use under tlie names of the four princi- pal alkaloids. It is specifically stated that liydroquinidine ac- 94 CINCHONA ALKALOIDS. companies commercial qxiinidine ; that hydrocinchonidine and cinchamidine are found with commercial cinchonidine, and that cinchotine sometimes contaminates cinchonlne. Hydroquinine may go with manufactured quinidine or quinine, being found in the motlier-liquors of the former. Quinamine, and probably conquinamine, are found in other barks besides " cuprea " bark, and may find their way into manufactured salts, where they should then be detected by reactions with sulphuric and nitric acids. Then the amorphous products quinicine and cinchonieine may be carried into crystalline forms of salts to some extent. And it is always understood that separations of cinchona alka- loids in manufacture are not absolute, so that the quinine salts of the market always contain, under certain limits, cinchonidine and cinchonine, perhaps quinidine, and under narrower limits may contain the amorphous alkaloids in general. The quinidine of commerce, according to Hesse, 1875, consists most often of cinchonidine with a little quinine. Amorphous cinchona alkaloids. — The name Chinoidme {Qni- noidine) was given by Sertiirner, in 1828, to the amorphous alka- loidal substance left after separating quinine and cinchonine as then known, and which he believed to be a distinct alkaloid. Chinoidine was recognized as an easily fusible base, of strong alkalinity, forming uncrystallizable salts, and of full virtues as a febrifuge. Until about 1855 it was prepared, in connection with the crystallizable alkaloids, by uniform methods, from Calisaya barks of good strength, and therefore possessed a fairly constant character. About 1817 Winckler stated that chinoidine was in large part an amorphous transformation product of the crystalli- zable alkaloids of cinchona then known. During investigations commencing about 1 853 Pasteur made it known that by fusing for some time a salt of one of the crystallizable alkaloids, or, in part, by hot digestion in acidulous solution, an amorphous modi- fication is obtained, without change of elementary composition. The amorphous product of quinine and of quinidine he narried Quliiiclne ; and the amorphous product of cinchonine and of cinchonidine he named Cinchonieine ; and it has been generally believed that these are the uncrystallizable alkaloids which exist already formed in the barks, as well as result from chemical treat- ment of the barks. All barks contain amorphous alkaloids; sometimes the larger portion of the alkaloids is amorphous. And the amorphous alkaloidal matter of cinchona has been in great part accounted for according to the nomenclature of Pasteur, almost down to the present time, so that we have had the familiar classification of the leading natural cinchona alkaloids, as follows; CINCHONA ALKALOIDS. 95 C20^~l-H-^-j^ \> • Qwinine, Quinidine, [Quinicine]. C20H04X2O : Ciiiclionine, Cinchonidine, [Cinchonicine]. Howard, in 1872. found quinicine and cinchoriicine, made from quinine and cinchonine, to be capable of crystallizable com- binations, while no salts crystallizable could be produced from natural amorphous alkaloids. And Hesse affirms (1878) that quinicine and cinchonicine, as isomers of ({iiinine and cinchonine, are not present in the barks, are not formed to any great extent by ordinary methods of manufacture, and not found in chinoidine. They would be formed in the manufacturing treatment, the melt- ing of chinoidine, only so far as the crystallizable alkaloids are subjected to this treatment, for it is stated by Ilesse that the chief natural amorphous alkaloids, taken from the bark or from chinoidine, are not convertible into quinicine or cinchonicine, which are partly crystallizable. The most prominent natural amorphous alkaloids, those making up the larger part of the by- product chinoidine, according to Hesse, are (with a little liberty in translating Hesse's nomenclature) diquinicine and dicinchoni- cine, amorphous alkaloids having the constitution of anhydrides (apo-derivatives) respectively of quinine and cinchonine (see the equation under Diquinicine, p. 91). In this view the leading natural cincli(jna alkaloids are to be grouped as follows : Crystallizahle. Amorphous. C 20^1 2-^ 2^^ i : Quinine, Quinidine. C^oH^gN^Og : Diquinicine. Ci9H„2Xo(J : Cinchonine, Cincho- CggH^gN^O {'.): Dicincho- nidine. nicine. By heating the chief crystallizable cinchona alkaloids with hydrochloric acid, at 140° to 150° C, in sealed tubes, for 6 to 10 hours, Hesse (1880)' obtained an apo-derivative from each. Apoquinine and apoquinidme each had the formula CjgHooK^.O.j , the removal of CHg being effected by production of CH3CI, and both these new alkaloids were found to be amorphous in all their salts. They gave the thalleioquin reaction, wcie soluble in ether or alcohol, and showed fluorescence. Apocinchonine and apo- cinchonidine were each CipH„..]Sr.,0, isomeric with cinchonine, and each was crystallizable. But a iViapncivclin'nine, ^z^^'P-z 1 forming only amorphous salts, was obtained, readily solubk' m alcohol, ether, or chloroform, and, ITesse states, distinct from the natural alkaloid dicinchonicine (p. 91), as well as from cinchoni- cine, formed by melting. ' B'r (Init rhem,. (lea , 205, 314; Jour. Ohem. Snc, 1881, Abs., 615; Atn Jour Phar., 53, 105, 160. 96 CINCHONA ALKALOIDS. The amorphous alkaloids difficult of separation have been less satisfactorily studied than the crystallizable ones, and it is strongly probable that dii|uiiiiciue and dicinchonicine very imper- fectly represent the amorphous alkaloids of the barks. Cliinoi- dine usually contains quiuidine in proportion larger than that of the other crystallizable alkaloids. Further than this it has as yet only been ascertained, that quinamidine and quinamicine are amorphous alkaloids found in some other barks besides those of Remijia ; and that cuscouine, chairamidine, and paytamine are amorphous accompaniments of the special crystallizable alkaloids of certain exceptional barks. Elementary analysis has been ob- tained of all these except paytamine. Yield of Cinchona Alkaloids. Of total alkaloids : ' In barks of different species and localities, from a maximum of about 15 per cent, to entire absence of alkaloids. " Calisaya Ledgeriana, Java, 80 specimens, Moens, 1879, 12.50 to 1.09 per cent. " Calisaya Javanica, De Vrij, 1879, 10.3 to 1.3 per cent. " Cinchona officinalis, Beoughton, 1872, 6.9 to 3.1 per cent. " C. succirubra, Java, 1881, 9.8 to 3.2 per cent. " China regia, 1855, 0.99 per cent. In China cuprea, 5.9 to 2 per cent. " "Cinchona" of IT. S. Ph., dried at 100° C, at least 3 per cent. " " Red Cinchona Bark " of Br. Ph., between 5 and 6 per cent. " " Cinchona Barks" of Ph. Germ., at least 3^ per cent. " Cinchona barks. Ph. Fran., at least 2|- per cent. In Red barks, at least 3 per cent. Of Quinine : In Cinchona succirubra, Java, harvest of 1881, Moens, 2.5 to 0.4 per cent. " C. Ledgeriana, Java, 1879, 11.6 to 0.8 per cent. " C. officinalis, India, 1872, Beoughton, 4.18 to 1.6 percent. " "Red Cinchona" and in "Yellow C," dried at 100° C, U. S Ph-, at least 2 per cent. " "Red Cincliona bark," Br. Ph., at least 3 per cent, quinine and cinchonidine. ' For a report of the yield of individual and total alkaloids in 13 Bolivia Cinchona Barks, see Stobdek, 1878: Archiv d. Phar., [3], 13, 243; Am. Jour. Phar.,51,22. CONSTITUTION. 97 In Eed Cincliona bark, Ph. Fran., at least 2 per cent, quinine as sulphate. Of (Jinchonldtne : In C. succirubra, Java, harvest of 1881, Moens, 5.2 to 1.3 per cent. " C. Calisaya, 1873, Moens, 8 samples, 1.2 to O.-i per cent. Of Chichon ine : In C. Calisaya, 1873, Moens, 8 samples, 1.1 to 0.1 per cent. " China de Quito rubra, Reichaedt, 0.39 per cent. " China Huauuco, Reichardt, 2.24 per cent. Of Qutnidlne : In C. CaHsaya, 1873, Moens, 8 samples, 0.9 to 0.86 per cent. " China cuprea, in comparative abundance, Gehe & Co., 1884. Constitution of CincJiona Alkaloids. — The derivation of cin- chonine and quinine from Quinoline, CgH^N, inferred Ijy Weidel in 1873, has acquired additional light every year, and promises to become clearly understood. The remarkable interest of the pyridine series and the derived quinoline series, in relation to natural alkaloids, is mentioned under Midriatic Alkaloids, with a statement of the central ^Josition of pyridine in the theoreti- cal chemistry of natural alkaloids. Quinoline vras obtained by Gerhardt in 1842 l)y distilling quinine with potash, and is so obtained from certain other alkaloids, cinchonine, strychnine, brucine. It is also found in consideralile quantity in the heavier distillates (dead oil) from coal-tar. The hypothetical formula of pyridine and quinoline, as aromatic compounds analogous to ben- zene and naphthalene, with N in the place of one CH in the benzene ring and naphthalene double ring, was proposed about 1870. The midriatic base tropine is derived from pyridine. The synthesis of quinoline has been effected in several ways; that by Skraup in 1881, from aniline, nitrobenzene, and glycerine, is a practical working method, yielding quinoline identical with that distilled from cinchona alkaloids: iCgll^N (aniline) +CeHsXO., (nitrobenzene) + ?,C^YLf>^ (glycerine) = SC.II^N" (quinoline) + IIH./). Since about 1880 there has been a most active interest in the field of pure chemistry lying between the quinoline series on the one side and the natural cinchona alkaloids on the otlu'i- side. A vast amount of well-directed experimental work has been done, and great numbers of derivatives, both of the quino- line bodies and of cinchona alkaloids, have been produced and 98 CINCHONA ALKALOIDS. examined. It is an opinion sustained by men acquainted with the methods and difficulties of organic syntliesis that quinine will be produced artificially. Meantime artificial quinoline de- rivatives, such as those brought before the world as Kairines,, have been found to present physiological effects like those of quinine. As to the commercial production of quinohne itself, as a medicinal material, should its products come into general demand, it would perhaps continue to be made from cinchonine,. unless manufacturers should exercise great care, in its production by Skraup's process, to avoid contamination with nitrobenzene (p. 97). It IS to be observed that both pyridine and quinoline bases have the characteristic of holding Hg, H^, Hg in addition com- binations. The hydrogenized members of the quinoline series (hydroquinolines), with ^•arious substitutions, take character ap- proaching that of the natural alkaloids. The gradually accumu- lating evidences, to which references are below given, render probable the following rational formulae., with two quinoline nuclei in the alkaloid molecule : Cinchonine: CgH^LoN. CgllgN.vO.CHg) ^Q^^l.,.^,0. Quinine : CgH^oN . CgHgN . (O . G^^^-^Q^^~^~^Q>^. Both quinoline and pyridine tend to form tetra-hydrides ; and tetrahydro-quinoline, C9Hy[Il4]]Sr, or CgH^^N, is fruitfiil of de- rivatives having resemblances to natural alkaloids. In the hypo- thetical formulfe for cinchonine and quinine, the quinoline tetra- hydride molecules drop an atom of hydrogen for union with each other, and another atom of hydrcigen for each molecule of meth- oxide (O.CH3) taken. The systematic names, therefore, are respectively methoxy-tetrahydro-diquinoline and dimethoxy- tetrahydro-diquinoline. ' ' L. Hoffman and W. Kontgs, 1883: Ber. deut. chem. Ges., 16, 727; Jour. Cheni. Soc. 1883, Abs., 1148. Konigs, with Comstock and with Feer, 1885, 1884, with G. KOrneu, 1884. Konigs. 1881: Ber. deut. chem. Ges., 14, 1852; Jour. ahem.. Soc, 1883, Abs., 224: 1880: Ber. deut. diem. Ges., 13, 911. Skraup, 1879: Ber. deut. chem. Ges., 12, 1107: Jour. Chem. Sue, 36, 810. "VViciiNBGRADSKY (stnittiire of cinchonine with both a quinoline and a pyri- dine nucleus), 1881: Bull. S"C. Chim., [2], 34, 339; Jour. Chem. Soc, Abs., 444. I)e Coninok, 1882-83. Knorr and Antrick (positions in the structure of quino- line), 1884: Ber. dent. chem. Ges.. 17. 2870, 2032; Jour. Chem. .'-■oc, 1885, Abs., 273: 1884, Abs., 1378. Claus and others. Diquinolines : Williams, 1881, r/iem. News, 43, 145: Claus, 1881-82; Dewae, 1881; Tressider, 1884; Fisch- er (and Loo), 1884, 1885; Oestermatee, 1885. Krakau, 1885. Berend, Hartz, Kahn, Spady, Einthorn. 1885-86. Michael. 1885: Am. Chem,. Jour., 7. 183. " Ladenburg's Handworterbuch der Chemie," i. 243-298, ii. 532-595 (63 pages on quinoline). Summaries of progress, 1883-85: Am. Chem. Jour., 4, 64, 157; 5, 60, 73; 7, 200, (183). COMPARA ri J 'E CHA RA C TERIS TICS. 99 o «1 <^ » ^ -^ ■__ e 740 parts vater e in 2o parts of e e in some excess ystals but very s ;u ^ OJ ,- "*"- Iphiites soluble Normal tartr ui l-H D ui "z l-H Q I— 1 E3 Stals take 125 ition. in 30 parts eth in 100 ])arts of in larger exc s C ^-3 -s i^s 3 rjj c s Ss3-e m i-i M 3 = phate ta lution. alnid sol aloid sol ■apnthite soluble. 03 Hydriodide water fo: Alkaloid sol Sulphate sol Alkaloid sol mania. ■T) -^-^ J M -^^ tq ^ 3 ^ S o5 JS § = M J. S S" ?3 Vj CD S 5 *" ^ '" "^ -c: w^ ^' '^ o— r: "o ^^ a 2 i; rt^ ^ «w o ^ -- tS a b ►- o ^^ c«o o 5 soS o g- _ -§_« o«J M. O CJ -c . M c S 5 lOO CINCHONA ALKALOIDS. Cinchona Alkaloids, Distinctions hetween (for test-metliod.«, conditions, etc., see under eacli alkaloid, d) : I. Of Quinine. A. — From ClncJionidiiie anil Cinohonine : 1. Fluorescence, in aqueous solutions of the sulphate and other- oxy-salts. 2. The thalleioquin test — with bromine or chlorine followed by ammonia. 3. Sulphate crystallization. ) -p, . -, . . -, . o 1 J.- ■ 'ii f Jtrom cmchonine more perfectly 4. holution m ether. >• t.^ c • i • v '' c- o 1 X' • • than from cinchonidme. 5. boiution-in ammonia. ) 6. Formation of herapathite, a crystalline iodosulphate. 7. Rotatory difference : from cinohonine, in direction ; from cin- chonidine, in degree. 8. Microchemical examinations (p. 101). B. — From Quinldine : 1. Sulphate crystallization. 2. Non-precipitation Ijy potassium iodide. 3. J^on-solution of the sulphate in chloroform. 4. Formation of herapathite. 5. Rotatory differeuce, in direction. II. Of Cinchonidine. A. — From Quinine (I. A, 1, 2). B. — From Cinchonine : 1. Tartrate precipitation. 2. Chloroformic solution of sulphate. 3. Rotatory difference, in direction. 4. Greater solubility in alcohol and in ether. C. — From Quinidine : 1. Tartrate precipitation. 2. ISTon-precipitation by iodide. 3. JSTon-solution of sulphate in chloroform. 4. Rotatory difference, in direction. III. Of Amoephous Alkaloids. A. — From the crystaUizaMe alluloids : 1. By non-crystallization of the sulphate, and other salts, and the free alkaloid, under ordinary or microscopic observation. B. — From Ginchonine : 1. By greater solubility in ether, or in dilute alcohol. MICROCHEMICAL DISTINCTIONS. loi 3£u'r amyl alcohol and benzene (Br. Phar., 1885). 4. The powder mixed with lime is exhausted by digesting and wasliing with alcohol (De Veij, 1873; U. S. "Ph., 1880, p. 78). 5. The acidulous decoction, in a part of the filtrate taken as a fraction of the total solution, is precipitated by picric acid, and the dried precipitate weighed (Hagee, 1869 ; given in this work under Allcaloids, p. 49). The use of an extraction apparatus, best adapted to ether as a SEPARATION AND ESTIMATION. 103 solvent, is a most rigidly exact and generally satisfactory way in this as in most solvent operations npon plants. But it loads the solution with more coloring and other extraneous matters, and takes longer, than the method placed first above. An aliquot part of the liquid, taken with due precautions, gives the operator ■quick and trustworthy results, and for ordinai-y uses this plan is here given the preference. Other operators prefer percolation or hot digestion, or both. The plans above enumerated have been carried out, in many cases with separation of the alkulitids from each other, or of the quinine from tJie other alkaloids, by different chemists, as follows : 1. Jlethods on the Plan of P roll i us.' — The directions of the German Phannacojiwia of Isy^i are in effect as fullows: Pre- 'Peollius, ISyl: Arch. d. Phur., 209, 85, 573; Am. Jour. Phar., 54, 59; Kew Rem., 11, 3:3. J. Biel, 1883: Pliar. Zeitschr. Russland, 21, 350. De Veij, 1883: Jour, de Pliar. et deCliim.; Sew Hem., 11, 358; Am. Jour. Phar., 54, 59. Kissel, 1883: Arch. d. Phur., 220, 130. Ph. Germ., 1882, 63. Fluck- IGEE, 1883: Phar. Zeit., vol. 28 ; Xeiv Ue>n., 12, 374. A. Pettit, 1884. Ci- tations from above-niiiiK'd autlioritie?-: Zeit. anal. Chein., 22, 133; Pruc. Am. Pharm.. 30, 304; 31, 133, 134. Prollius proposed the ethereal solvent mixture (making it by weight of ether 88 per cent., of amraonia-watei- 4 per cent., of 93 lo 9lj piT cent alcohol 8 per cent.) for assays of the ether-soluble alkaloids only, and directed a chloroform mixture for assays of the total cinchona alkaloids. But Biel, and Kissel, and De Vrij agree in the statement that ProUins's ethereal solvent removes all the alkaloids. Prollius, however, used only half as much of the solvent as is here directed, according to De Vrij. Do Vrij emphasizes the required fineness of the powder. He would prefer a less aqueous solvent, made by saturatinir the alcohol with ammonia, and adding the ether. Biel says the time of maceration should be four hours, neither more nor less, while De Vrij found one hour enough as shown by control experiment. Kissel obtains the quantity of the pure alkaloids by subtracting from the quantity of crude alkaloid the weight of resins, wax, etc., left on a tared filter, in filtration of a solution of tlie crude alkaloidal residue in diluted sulphuric acid. — The chloroforniic solvent of Prol- lius, above refen'ed to, consi.-^ted of 76 percent, alcohol. 20 percent, chloroform, and 4 per cent, ammonia-water. The solution was wine-red, and to decolorize it a quantity of finely powilered calcium hydrate equal to the quantity of the bark is agitated with the decanted solution, which is then filtered, and this fil- trate is weighed to obtain an aliquot part of the entire solvent taken. The weighed filh-ate is ev.iporated, and the dried residue weighed as total alkaloid, not purified further. — In the use of the ethereal solvent Prollius decanted the -clear solution (as in the directions above), and then supersaturated the ethereal solution with diluted sulphuric acid, when the alkaloidal sails were found in a dense aqueous layer. The ethereal layer was removed and washed, once with 2 C.C., then with 1 c.c. of water, the washings >)eing added to the alkaloid solu- tion. From the latter the alcohol is evaporated, when ammonia is added just to alkaline reaction, and the precipitate dried in a tared capsule and weighed. — The ethereal solution, if not distilled, should be evaporated in a flask or beaker of some depth to avoid ci-eeping. — The purification of the crude alkaloids is a matter distinct from the removal from the bark, and may be varied at will of the operator. The separation by shaking out with chloroform (p. 33) will gene- rally be preferred t;o precipitation by the Ph Germ. 104 CINCHONA ALKALOIDS. pare the solvent mixture by taking together 85 parts by weiglit of ether (s.g. 0.Y24 to 0.728), 10 parts of alcohol (0.830 to 0.834), and 5 parts of ammonia-water (s.g. 0.960), making 100 parts by weight. — Treat 20 grams of the powdered cinchona with 200 grams of the solvent mixture, agitating thoroughly and repeat- edly, macerate one day, and pour off 120 grams of the clear liquid. — Add 30 c.c. of decinormal ' solution of hydrochloric acid, remove the ether an- sule tared with a short glass rod (i-insing with a little of the sol- vent), and evaporate and dry the residue on the water-hath. Weight of alkaloidal solution decanted from the hottle : weight of total solvent taken in the huttle :: weight of residue : j:. = quantity of crude alkaloids in the amount of hark taken. — To obtain the pure alkaloids, the residue of the crude alkaloids is dissolved in diluted hydr(_ichloric acid, the solution filtered and the filter washed, the nitrate made alkaline with sodium hydrate and repeatedly shaken out tullh cJdorofonn, the chloroformic solution evaporated (or distilled) in a tared dish, and the residue dried at 100° C. and weighed. De Vrij found the pure alkaloids so obtained to be 16.5^ less than the crude in the case of a red Java bark. 3. Remoiyal of the Alkalo'tdn from the liurk hy vse if an^ Extrnction Apjxtratas. — For the use of an extraction apparatus upon cinchona Ixirk, with etJirr as a solvent, the following ex- cellent directions of Pi-ofessor Fluokigee are given: ' Of a well- selected average specimen of the bark 2() grams are very finely powdered, moistened with ammonia-water, and, after standing for an hour, mi.xed with so grams of hot water; it is then al- lowed to cool, subsequently mixed with milk of lime (j^repared by triturating 5 grams of dry caustic lime with 50 grams of water), and the mixture evaporated on a water-bath until it is uniformly converted into small, somewhat moist, crumb like j^ar- ticles. This is then transferred to a cylindrical glass tube about 2.5 centimeters (1 inch) wide and 16 centimeters (0.1 inches) long, the tube being fitted as the percolator of an extraction apparatus. The neck of this percolator is fitted with a rest of wire cloth, on which a disk (jf filtering-paper is held by a loose plug of cotton. The powder is packed (piite compactly, and covered, at the top, with a plug of cotton which has been uslmI to clean away the last ti-aces of the bark. The percolator is put in place, under a condenser, in the extracti(.in apparatus, into the receiver of which about 100 c.c. of ether is introduced, and the extraction is conducted, in the usual manner, over a water-bath for nearly a day, and until coinpleted as shown by testing a little of the percolate. This may be tested, in the ' " The Cinchona Barks,'- Power's translation, Pliila., 1884, p. 69. Othrr solvents have been used nn cirichoTia with an exi ruction apparatus. Chloroform is used in Carles's process (187:i: /Cdfuch. until. C/iem., 9,497). Methylated Bl her, and doubtless alcohol or iMethylaled Alcohol, can bo well used in a form of ex- traction apparatus that would carry over the vapor with desirable rapidity. io6 CINCHONA ALKALOIDS. ethereal solution, by about an equal volume of potassium mer- curic iodide solution." When the extraction is completed, 36 c.c. of decinormal solution of hydrochloric acid (3.6i grams in 1 liter) are added to the ethereal solution in the receiver, when the ether is distilled off, and enough hydrochloric acid then added to give an acid reaction. When cold the liquid is filtered, the filter washed, and 40 c.c. of decinormal solution of soda (4 grams in 1 liter) are added. The precipitate is left at rest till the hquid above it is clear. Sodium hydrate solution (preferably of spec. grav. 1.3) is then added to complete the precipitation, the precipitate is col- lected on a filter, and gradually washed with a little cold water until a few drops of the washings, when allowed to flow on the surface of a cold-saturated neutral aqueous solution of quinine sulphate, cease to produce a turbidity. The drained precipitate contained on the filter is then gently pressed between bibulous paper, and dried by exposure to the air. It may afterward be readily removed "from the paper without loss, and, after tho- rough di-'ying upon a watch-glass over sulphuric acid, is finally dried at 100° C. and weighed. The weight of the precipitate, multiplied by 5, will give the total percentage of mixed alkaloids in the bark. B. The tise of ethereal or IjeiizoJa.ted mixture of Arayl Alcohol to d'lsnolve the free clnrhnna alkatoiils, lohich are then trans- ferred to aiiueovs tiolutlon of tlie salts of theae alkaloids. — A. — SqulWs Process:'' " Take of tlie powdered cinchona 5 grams ; lime, M'ell burnt, 1.^5 grams ; amyl alcohol, stronger ether, puri- fied chloroform, normal s c c] of benzolated amyl alcohol [amyl alcohol, 1 volume ; benzene of sp. gr. about 0.8.50, 3 vols.], boil them together for about half an hour, decant and drain ofl' the liqi^id on to a Alter, leaving the powder in the flask ; add more of the benzolated am}-l alcohol to the powder, and boil and de- cant as before ; repeat this operation a third time ; then turn the contents of the flask on to the filter, and wash by percolation with the benzolated amyl alcohol until the bark is e.xhausted. If during the boiling a funnel be placed in the mouth of the flask, and another flask filled with cold water be placed in the funnel, this will form a convenient condenser which will prevent the loss of more than a suiall quantity of the boiling liquid. Introduce the collected filtrate, while still warm, into a stoppered glass sepai-ator ; add to it 20 minims [1.1 c.c] of diluted h)'dr(j- chloric acid [of 10. 58;^ i-eal acid] mixed with :3 fiuid-drachms [T c.c] of water; shake them well together, and when the acid liquid has separated this may be drawn off, and the process repeated with distilled water slightly acidulated with hydrochlo- ric acid, until the whole of the alkaloids have been removed. The acid liquid thus obtained will contam the alkaloids as liy- drochlorates, with excess of hydrochloric acid. It is to be care- fully and exactly neutralized with ammonia while warm, and then concentrated to the bulk of 3 fluid-drachms [about 10 cc] If now about 1.5 grains [0.97::^ gram] of tartarated s(.ida [potas- sium sodium normal tartrate], dissolved in twice its weight of water, be added to the neutral hydrochlorates, and the mixture stirred with a glass njd, insoluble tartrates of quinine and cin- cbonidine will separate completely in about an liour ; and these collected on a fllter, washed, and dried, will contain eight-tenths of their weight of the alkaloids, quinine and cinchonidiuH^ which [in grains] divided by 2 [or in gi-ams midtiplied by S] re])re- sents the percentage of those alkaloids. The other alkaloids \y\\\ be left in tiie mother-liquor." — (2) For total alhiloiih: ''To the mother-liquor from the preceding process add solution of ammonia in slight excess. Collect, wash, and dry the precipi- tate, which will contain the other alkaloids. The weight of this precipitate [in grains] divided by 2 [or, in use of the metric no CINCHONA ALKALOIDS. quantities, its weight in grams multiplied by 8], and added to the percentage weight of the quinine and cinchonidine, gives the percentage of total alkaloids." 4. The use of alcohol to dissolve the free cinchona alkaloids, tht-n obtained hy vrecipitatioti from aqueous solution.' — The di- rections of the tl. S. Ph. are as follows : ^^ For total alkaloids: Cinchona, in ISTo. 80 powder, and fully dried at 100° C, 20 grams ; lime, 5 grams ; diluted sulphuric acid, solution of soda, alcohol, distilled water, each a sufficient qiiantity. Make the lime into a milk with 50 c.c. of distilled water, thoroughly mix therewith the cinchona, and dry the mixture completely at a temperature not above 80° C. (176° F.) Digest the dried mix- ture with 200 c.c. of alcohol, in a flask, near the temperature of boiling, for an hour. When cool pour the mixture upon a filter of about six inches (15 centimeters) diameter. Rinse the flask and wash tlie filter with 200 c.c. of alcohol, used in several portions, letting the filter draiu after use of each portion. To the filtered liquid add enough diluted sulphuric acid to render the liquid acid to test-paper. Let any resulting precipitate (sulphate of calcium) subside ; then decant the liquid, in portions, upon a veiy small filter, and wash the residue and filter with, small por- tions of alcohol. Distil or evaporate the filtrate to expel all the alcohol, cool, pass through a small filter, and wash the latter with distilled water slightly acidulated with diluted sulphuric acid, until the washings are no longer made turbid by solution of soda. [Alternutive direGtiuiis^ from this jyoint, given ielow.^ To the filtered liquid, concentrated to the volume of about 50 c.c, when nearly cool, add enough solution of soda to render it strongly alkaline. Collect the precipitate on a wetted filter, let it drain, and wash it with small portions of distilled water (using as little ' De Vrij, 1873: P/iar Jour Trans , [3], 4, 241 ; Proc. Am. JPhar., 22, 268. U. S. Ph., 1880, p. 78. A. B. Presoott in "Report on the Revision of the U. S. Ph.," New York, 1880, p. 26. This is a direct and simple method, in common use and giving good results. The precipitation and washing is open to the objection, elsewhere noted, that quinine thereby suffers a little loss. This is avoided in the aUertiative modifica- tion bj shaking out the total alkaloids with chloroform, given here from the " Report on Revision." GcEBEL (1884: Prnc. Am. Pliar.. 32, 474) proposes, very properly, the adap- tation of the process to the pilan of taking an aliquot part of the alcoholic solu- tion, as in Prollius's method, as follows: " Place 15 gramsof cinchona — treated with milk oE lime and perfectly dried — in a flask, add 150 c.c. of alcohol, weigh the whole, digest the loosely stoppered flask and contents for about tvpo hours at 150° to 160° F., cool, replace the slight loss of weight by alcohol, filter, through a covered filter, 100 c.c. equivalent to 10 grams of the bark, and proceed with this extraction practically as directed by the Pharmacopoeia." SEPARATION AND ESTIMATION. iii as possible) until the washings give but a slight turbidity with test-solutiou of chloride of barium. Drain the filter by laying it upon blotting or filter papers until it is nearly dry. " Detach the precipitate carefully frona the filter and transfer it to a weighed capsule, wash the filter with distilled water aci- dulated with ililuted sulphuric acid, make the filtrate alka- line by solutioti of soda, and, if a precipitate result, wash it on a very small filter, let it drain well, and transfer it to the capsule. Dry the contents of the latter at 1U0° C. (212° F.) to a con- stant weight, cool it in a desiccator, and weigh. The number of grams multiplied by five (5) equals the percentage of total alkaloids iu the cinchona." Alteniatii^e directions from point above noted : Concentrate the filtrate to the volume of 50 c.c. or less. Transfer, rinsing with a little water, to a glass separator of 100 to 15(1 c.c. ca- pacity. Add solution of soda in decided excess, then at once add 30 to 40 c.c. of chloroform, stopper, agitate for a few minutes, set aside for an hour or two, and draw off the clear chloroform layer. In the same way extract with three smaller portions of the chloroform, using in all at least 120 to 130 c.c. of this solvent. The chloroform is then recovered by distilla- tion or is slowly evaporated, the concentrated liquid is trans- ferred, with chloroform rinsing, to a weighed dish, and the re- sidue dried on the water-bath to a constant weight. The grams multiplied by 5 express the percentage of total alkaloids in the bark.' Sepaeation of Cinchona Alkaloids fkoh Each Other. I. Separation of Quinine. A. — From other cinchona allcaloidn in general^ 1. By crystallization of the sulphate in aqueous solution (p. 113). 2. '• crystallization of herapathite (under Quinine, f, "Hera- pathite " ). 3. " solution in ether (p. 116). 4. " solution in ammonia (see under Quinine, g, " Kerner's Test " ). ' "This I find," shaking out with 50 c.c, and then with three .succTssive portions, each of 2.5 c.c. of cliloroform, "will lirinf? li.ick invariably .'i.OO out of 6.00 grams of pure mixed alkaloids, and is decidedly the most accurate molhod, given practice in the way of shaking, elc, so as to get the chloroform to settle quickly."— J, Muter, 1880: The ylMo/i/.^Mjondon, S, 223. "^ There may be added, for trial, (5) separation by precipitation as Oxalate^ .Shinioyama, 1885: Archiv d. Phar., [3], 23, 309. 112 CINCHONA ALKALOIDS. B. — From Cinchonidlne. 1. By recrystallizations of the sulphate (p. 113). 2 " solution in ammonia, in filtrate from saturated sulphate (p. 117). C. — From Qiiinidine. 1. By non-precipitation with potassium iodide (see Quinidinej f). 2. '' non-solution of the sulphate in chloroform.' 3. " precipitation as normal tartrate. D. — From Cinclionine. 1. By non-solution of the sulphate in chloroform.' 2. " precipitation as neutral tartrate (compare " Separation of Cinchonidiue," p. 118). E. — From Amorjphous Alkaloids. 1. By crystallization of the sulphate. II. Sepakatiom- of Cinchonidine. A. — From other cinchona alkaloids in general. 1. After removal of Quinine, by precipitation with normal tar- trate (p. 118). 2. By precipitation as tartrate, followed by removal from Qui- nine by I. A. 1, 2, 3, or 4. B. — From Cinchonine and Quinidine. 1. By non-solution of the sulphate in chloroform. 2. " precipitation as neutral tartrate (p. 118). C. — From Quinine. 1. By non-crystallization as sulphate, repeated (p. 113). 2 " solution in excess of ammonia after filtration of sulphate (p. 117). D. — From Amojyhous Alkaloids. 1. By crystallization as normal tartrate (p. 119). ■ Taken separately, quinine sulphate and cinch onidme sulphate each re- quires abont 1000 parts of chloroform for solution, while quinidine sulphate dissolves in 20 parts, and cinchonine sulphate in 60 parts, of this solvent. Taken in mixtures of quinine or cinchonidine with quinidine or cinchonine, these differences of solubilitv are seriously diminished (the author with Mr. Thum, 1878: Proc. Am. Pharm., 26, 831). SEPARATION OF QUININE. 113 III. Separation of Cinohonine. A. — From other cinchvnn alkalo'idx /;/. (ji'iierid. 1. By nou-solutiou in ether (p. 116). 2. " more sparing solution in alcohol. B. — From Qitiiiliw. 1. By not crystalliziiiii; as wulpluite (sue below). 2. " solution of the sulpluite in eliloroform (see note on p. 112). Q.—From L 'inchonidlne. 1. By solution of the sulphate in chloroform. 2. " non-precipitation as neutral tartrate (p. 119). D. — From QuiniJine. 1. By non-precipitation with potassium iodide (Quinidine, e). E. — From Amorphous Alkaloids. 1. By dilute alcohol. 2. " ether. Sepaeation of Quinine (I. A, 1) frotn other cinchona alka- loids in general, hy crijstidlization of the sulphate in aqueous solution — The solubilities of the sulphates of the four alkaloids in water at 15° C. (59° F.) is, respectively, (juinine, 740 parts; quinidine and cinchonidine, each 100 parts ; einchonine, 70 parts. The comparative insolubility of quinine sulphate in cold water is the most trusty factdr in Kerner's test for quinine, offi- cial in U. S. Ph., in Pii. (Term, since 187^, and in the Ph. Fran., 1SS4.' Sulphate insolubility alsti enters into the Br. Ph. test The insoluhility of quinine sulphate is not materially affected by the presence of other cinchona alkaloidal sulphates,^ which is, unfortunately, not true of the solubility of quinine in ether, or of the insolubility of quinine sulphate in chloroform. To effect complete separations, however, several recrystalliza- tions are necessary. Cinchonidine certainly opposes some^ resist- ance to separation from quinine. PIesse has recently reaffirmed ' that quinine sulphate is fully freed from as much as 2 per cent, of cinchonidine sulphate by two crystallizations from be li ling water. 'Kerneb. 1862: ZeilsKh. anal. ('h<"m., 1,150; Phar. Jour. Trans., [2], 4, 19; Am. Jour. Phar., 34, 417. 1880: Arc/ni> d. Phar., [3], l6, 186; 17,438; Junr. Chem. 80c., 40, 63 Koiner rests the separation in good part upon the action of ammonia in the filtrate. ■' The author and Mr. Thum, 1878 : Proc. Am. Pharni.., 26, 834. " Report' on Revision U. S. Ph.," 1880, \<\>. 39, 116. « Hesse, 1886: Phar. Jour. Tran.s., [3], 16, 818; (1885) [3], 15, 869. 114 CINCHONA ALKALOIDS. Da VIES (1885) ' found niiinerous recrystallizations necessary to obtain a salt with constant rotatory power. Keenee (1880)" found that three to six crjrstalhzations of commercial quinine sul- phate suffice to give a perfectly pure salt, as shown by a constant behavior in his ammonia titration. Keenee (1880) further states that in crystallizing from hot watery solution a slightly basic salt is crystallized. In this case the cleaned crystals become slightly alkaline to test-paper, while the filtrate becomes acidu- lous to a corresponding degree. To effect the utmost separation by one crystallization it is in- dispensable to hold the reaction of the initial solution exactly neutral, as a slight acidity increases the solubility of quinine sul- phate. In separations for estimation, therefore, the reaction should be neutral But in separation to prepare absolutely pure quinine salt, though at expense of partial loss, crystallization from acidulous solution is more efficient. De Yeij has advised to convert to the definite acid sul23hate [by adding as much more sulphuric acid as the quantity required to convert the free alka- loids into neutral salts] ; then crystallize the acid salt, recrystal- lizing as necessary ; and finally form the normal salt \y^ jjrecipi- tatiug one-half as the hydrate, and dissolving the washed precipi- tate in solution of the remaining acid salt. The following directions fur sejyaration of quinine as sul- phate are in effect those of the U. S. Ph., 1880 (p. T'J),' but with provision for better regulation of the use of acid and alkali, an increase of temperature in the digestion before crystallizing, and the di'ving to aidiydrous instead of effloresced sulphate. The unchanged pharmacopoeial text is enclosed in quotation-marks. " To the total alkaloids from 20 grams of cinchona, previously weighed," or to a weighed quantity (0.5 to 5.0 grams) of any ordinary mixture of free cinchona alkaloids, taken in a weighed beaker of capacity of about 120 fluid parts for 1 part of alka- loids, add from a burette decinormal solution of sulphuric acid until the liquid is " just distinctly acid to litmus-paper " and re- tains this degree of acidity after 15 to 30 minutes' digestion on 'Davies, 1885: Phar. Jour. Trans., [3], i6, 358. To same effect, Oude- MANS, Jahr. Chetn., 1876. It is surmised that a double sulpliate of ciiiclioni- dine and quinine crystallizes, according to Koppeschaar (1885) with 6H2O. See, also, Yungfleisoh. 1887: P/iar. Jour. Tram. [3] 17, Sn.T ^Kerner, 1880: Airln'v d. Phar., [8], 16, 191. As to the ammonia test, see under Quinine, g, "Kerner's test." Kerner found that heating the solution before the crystallizing at 15° C. had little influence on the result. 'Given first in the author's contribution to "Report on Revision U. S. Ph.," 1880, p. 26. Data taken from the report of Prescott and Thum, 1878: Proc. Am. Pharm., 26, 834. SEPARATION OF QUININE. 115 the water-batli.' Add now deciuorinal solution of soda from the burette until after stirring the reaction is " exactly neutral t -: cijntation ' Kernbb, 1863. Improved in 1880: Zeilsch. anal. Cheni., 20 .nV,; Arehw d. Pilar., [3], i6, 186-285; 17, 438-454; Jour. Chem. Soc, 40, 63 /Jiueusoion, in this work, under Quinine, g, " Kerner's Test." SEPARATION OF CINCHONIDINE. 119 whh normal titrtrate. — The quinine niay be removed (1) by crystallization as a sulpluite (p. 114), or (2) by solution in ether (p. 110). For tlw purpone of an eiithnntion, a (bduction of the quantity of qu'i nine iY^^va.\\\^ v^\M\'l\\-^' oi liotli quinine and cin- chonidine is quite sufficient. To this end tlie following direc- tions of Muter,' here slightly varied, serve well: The quinine is separated and estimated as crystalline sulphate (p. 114), A weighed portion of the mixed cinchnna alkaloids is dissoi\ed with hydrochloric acid enough to make the solution onlv slightly acid " to test- pa])er, and as concentrated as compa- tihle wifh solution at .'58° C. (or 10(»° F.) = The solution is made exactly neutral by adding sodium hydrate dilute solution, an ex- cess of the precipitant, a saturated solution of tartrate of jjotas- sium and sodium (Rochelle salt) is added, and the iiuxture kept at l.j° (\ (^50^ F.) for an hour, stirring frequently with a glass rod. The precipitate is collected on a pair of filters as small as practicable and previously (dried and) counterbalanced with each other, and is washed with, say, 100 c.c. of water at 15° C, the filtrate and wash- ings being receixed in a graduated measure. The precipitate is dried at 104° C. (or at 220° F.) and weighed, using the outer filter as a tare. For each c.c. of the total filtrate (>.nij()83 is added (]\[utee) to the weight of the precipitate. The weight of anhj'drous quinine sulphate is multiplied by 0.9151, or the weight of anhydrous quinine is multiplied by 1.231, to obtain the weight of anhydrous quinine tartrate, which is dediu/ted from the weight of the precipitate. The remainder is the weight of anhydrnus cinchonidine tartrate (C\gHo2X20)2Cj^rigO|, , which, multiplied by O.7907, gives the weight (if cinchonidine. (For following separation of remaining alkaloids see p. 12U). Hpparat'ion (f ('uirhonidine (XL A, 2) hij jirecipitation as tartrate, f't/onjrtl hy removal from Quitiine. This plan differs from the preceding only in the order of the successive steps. — In precipitating first as tartrate, in case of Commercial Quinine iSulphate, De "\ kij (1884) directs to take 5 gi-ams of the salt, in 200 c.c. boiling water, and add 5 grams of Rochelle salt previously dissolved in very little boiling water. After 24 hours collect on a filter, wash with the smallest quantity of water, and dry in the '1880: Analyst, 5, 334. 'Muter dissolves the mixed alkaloids in absolute alcnhdl, divides in two equal portions, taking one portion for quinine us a suliihalf The portion for cinolionidine is made just acid with hydrochloric acid, the alcohol evaporated off, and the residue dissolved in least quantity of water at 100° F. ' If the total alkaloids contain resins, kinic acid, etc , filter through a small filter, wash with as little dilution as possible, and if necessary concen- trate. 120 CINCHONA ALKALOIDS. air. — Kopp states that a double normal tartrate of quinine and cinchonidine crystallizes with 1 molecule of water. — Heilbig (18SU), following Dc Yrij, separates cinchomi alJialoids in gene- ral, b)' initial precijjitation of tartrates, as follows : 2 grams of the mixed alkaloids are dissolved as acetates in 30 c.c. of water, and the solution mixed with 1 gram Kochelle salt and well stirred. The precipitate is washed with care to avoid its solution, and dissolved in (10 per cent, alcohol acidulated with 1.6 per cent, of sulphuric acid, and herajjathite is formed (as directed under Quinine, /'). — The filtrate is treated with potassium iodide for precipitati(_in of cpiinidine. The filtrate from the latter is treated with soda, and the resulting precipitate, dried, is exhausted by absolute ether for removal of amorjDhous alkaloids, the remainder being cinchonine. For xeparat'wn of Cinchonidine, Qvinidine, Cinchonine^ and AniDi'pliOus Alkaloids from each other, after the estima- tion of Quinine, the directions of De Veij are as follows : " Two grams of the pulverized mixed alkaloids are dissolved in weak hydrochloric acid to obtain a slightly alkaline solution measur- ing 70 c.c. By adding 1 gram of Rochelle salt to this solution," heating, cooling, stirring, and setting aside, as above indicated, " the tartrates of quinine and cinchonidine are separated ; these are collected on a fiber, washed with a little water, and dried on a water-bath. One j^art of these tartrates represents 0.8nS4J: of quinine and cinchonidine : from the amount of these alkaloids thus found the amount of quinine already ascertained is sub- tracted, the remainder representing the cinchonidine present." — "In the filtrates from the tartrates, quinidine, if present, is pre- cipitated by a concentrated solution of potassium iodide [compare under Quinidine, d and f'\ ; one part of the dried Iwdriodide re- presents O.Sf>.504: part of crystallized quinidine [0.7175 part of anhydrous quinidine]." — " The remaining solution is treated with caustic soda, and the precipitate (if any) washed with ether. The residue represents the amount of cincJionine (compare under Cin- chonine, /")." — " Finally, by distilling the ether from the wash- ings can be ascertained the amount of amorphous alkaloid, which often, in the case of analysis of Indian barks, contains traces of quinamine." The directions of J. l\hTTER,' for separation of Quinidine, Cinchonine, and Amorphous ^Z/'«^//r/, taking the filtrate from Cinchonidine and Quinine tartrates (see p. 119), are as follows: " The filtrate from the tartrate is concentrated to its original ' 1880 : Analyst, s, 224. ROTATORY POWER. 121 volume [that before the washing of the precipitate is probably intended], coolei!, rendered just faintly acid by a drop of dilute acetic acid, and excess of saturated solutimi uf potassium iodide is added with constant stirring. After an hour or so at 15° C. [compare under Quinidine, /'] it is collected like the cinchoni- dine, and treated in every resjtect tlie same, and wciglicd, and the weight, having had O.onuTT added for each c c. of hhrate and washings, is nmltiplied by [0.7175], and n-sult is quiini/lui'." — " The filtrate from the quinidiue is made distinctly alkaline by sodium hydrate, and tlie precipitated cinchoninc and amorplious alkaloid are filtered out in a similar manner, washed, dried, and weighed. The precij)itate is then treated with alcoliol of 40 per cent, to dissolve out the amorplious alkaloid, and again dried and weighed, and the difference is amoTplidUK all-aloiil, while the last weighing is cinchonine." But " tlie weiglit of the cincbo- nine and amorphous alkaloid together must have deducted from it 0.00052 for eacli c.c. of the filtrate from the quinidine Iiydrio- dide, and O.<)0066 for each c.c. of the filtrate from the cinchoni- dine tartrate, and the balance is then tin- true weight, which, minus the amorphous alkaloid, gives the eineJidnine.''^ ROTATORY POWER OF CINCHONA ALKALOIDS. The plane of polarized light is deviated to the left by quinine and cinchonidine, to the right by (iuinidine and cinchonine. Further, the ilej:tro rotatory alkaloids include diquinicine, quini- cine, cinchonicine, concusconine, cojichairamine, cliairamidine, and cinchotine ; the terorntdtor;/ alkaloids include hydro(|uinine, hydroquinidine, hydrocinclionidine, homoquinine, cusconinc, con- chairamidine, paytine, aricine, and cinchamidine. — The degree of deviation, or specific rotatory power, varies between the free alkaloid and its salts,' and varies with different solvents, concen- trations, and temperatures. Quinine hydrate, in alcohol 97^^ vol., at 15° C, \a] D=-(145.2°-0.(;57c ') Hesse, 1875. Quinine hydrate in ether (0.7296), at 15° C, [a] D=— (15s.7°-1.911c) Quinine, anlivd., 5^;^ sol in chloroform, 15° C., [r/]D=-lor,.6° " " Between 15° (!. and 25" C'., when c=3, ab- solute rotatory powci- falls 1.56° " " 1 Further as to the iiifluenco (i[ Lhe iicids, Oudemans, 1883; as to influence of solvents, the same author, 18T8 'c = concentration, or grams in 100 c.c. of solution. « 122 CINCHONA ALKALOIDS. ■) (C Quinine sulphate, cryst., in alcohol 80j^ vol. (c=2), 15° C, [a] D= -162.95° Hesse, 1875. Quinine sulphate, cryst., in alcohol 60^ vol., (c=2), 15°C., [a.]D=-166.36° " Quinine bisulphate, cryst., in water, (c=l to 6), 15°C., [a]D=-(l(U.85°-0.31c) " " Quinine sulphate, anhyd., in water, (c=4), 15° C, [ffi]n=-229.03° " 1880. Quinine sulphate, anhyd., in water, (c=l), 15° C, [«] D= -232.7° Davies, 1885. Quinine sulphate, anhyd., in water, (0=4). 15° C, [a] D=-233.75° .' Hesse, 1886. Quinine sulphate, anhyd., in water, 17° C, [a] d :^_242 17° OUDEMANS. Quinine hydrochloride, in water, (c=l to 3), 15° C.; \a\ D=-(165.5°-2 425c^ Hesse. Cinchonidine, in alcohol of 97;j; vol., (c=l to 5), 15° C, \_a] D= -(107.48°-0.297c) " Cinchonidine sulphate, 6 nq., in water, (c=1.06), 15°C., [a]D=-106.77° " Cinchonidine sulphate, anhyd., in 'i.Xh^io sol. in alcohol, \a\ d=-153.95° With 0.40 gram of the salt, with 3 c.c. normal solution hy- drochloric acid, and water to make a volume of 20 c.c (" Con- centration A " of Oudeinans) : Quinine tartrate, cryst., [»] d^ — 215.8° Gudemans. Anhyd.=; — 220. 07° Koppeschaaje. Cinchonidine tart., cryst., [a] d= — 131.3° . . . . Oudemans. Anhyd. ^ — 137.67° Koppeschaae. Take 0.40 of mixed tartrates of quinine and cinchonidine (see under Separation of Cinchona Alkaloids by Tartrate, p. 119), dry at 125° to 130° C, dissolve as stated above for " Concentra- tion A," observe rotatory power (a), then, to find x ^ per cent, of quinine tartrate in the mixed tartrates : 220.07^ + 137.67 (100-a;)== 100a. And 100(^-137.67) . ^"""^ ^-220.07- 137. 67- For the estimation of cinchonidhie in commercial quinine ' KoppESCHAAB, 1885: Zeitsrh. anal. Chem., 24, 363; Jour. Ghem. Soc, 49, 182. OuDEMANS, 1875: Arch, neerland. des Sci., 10, 193; Jahr. Ghem., 1875, 140. Further, 1877 and 1884. ROTATORY POWER. 123 sulphate IIesse ' directs as follows : 2 grams of anhydrous com- mercial quinine sulphate, or an e([uivalent quantity of crystallized salts, are weighed in a tlask of 25 c.c. capacity, mixed with 10 c.c. of normal solution of hydrochloric acid, the flask filled up to the graduation-mark with water, and, after the contents are thoroughly mixed by shaking, the solution is poured through a filter into the observation tube, which is 220 millimeters long and is provided with a water-jacket for maintaining a constant temperature. From 12 to 20 observations are made with this solution, at 15° C, and the mean of the different readings is taken. Let c = the observed deviation at the d line, and y = tlie cinchonidine sulphate." Then, if the observation-tube be 220 m.m., ?/= (40.309 — c) X 8.25. For other lengths of the observation-tube let C =: the observed rotatory power, when ij ^= (229.03 — C) X 1.-452. Quinidine, deviation diminishes with elevation of temperature. Quinidine hydrate, in alcohol of 97^ vol., at 15° C, [a] D=+(230.77°-3.Olc) Hesse. Quinidine auhvd., in alcohol of 97''t vol., at 15° C, {((r\ D=+(269.5T°-3.42Sc) " Quinidine hydrochloride, in alcohol of 97^, at 15° C, [a]D=+(212°-2.502c) " Cinchonine, in alcohol, c=0.455, [a^ d=+214.8° c=r().5:35, = 2l;!.3° C=0.560, = 209.6° .... OtJDEMANS. Cinchonine sulphate, in water, c = 0. S55, [. — Quinine is odorless, and has a pure bitter taste of much intensity. The persistence and intensity of the bitter taste of quinine salts is in proportion to their solubility as brought in contact with the tongue. Of ordinary forms administered the tannate is the least and the free alkaloid next least bitter, the sulphate being less bitter than the bisulphate, liydrobromide, or hydrochloride. — Quinine is poisonous to tlie lower foi-ms of ani- inal life, in this effect being surpassed among vegetable poisons only by such as stryclmine and morphine (Binz). For frogs tlie fatal dose is 0.05 to 0.1 gram (| to 1^ grain) internally, or about 0.0025 (I grain) subcutaneously. For dogs about (».12 gi-aiii per kilogram (J gi'ain per pound) of body-weight proves fatal (Beenatzik, l«ii7). Infusoria and bacteria are destroyed with 128 CINCHONA ALKALOIDS. somewhat concentrated solations of quinine salts, quite variable strengths being required for different infusoria. — Quinine is antiseptic, hindering or stopping the alcoholic, lactous, butyrous, amygdalous, and salicylous fermentations (Binz, " Husemann's Piianzenstoffe," 1884), not the digestive action of pepsin. — Qui- nine is excreted hi the urine to the extent of 70 to 96 per cent, of the amount taken. It appears in the urine as early, fre- quently, as one hour, and usually disappears as soon as forty- eight hours, after ingestion (Keener, Juegensen, and Feau). Quinine is found in the liver. In some small part, also, it suf- fers conversion in the system into amorpho'us quinine [di- quinieine?], and an oxidation product, iJihydroxyl-quinine (C2orio4N204) (Keener), or, according to Skeatjp, Ohitenins (Cj^glloo 1^2^*4)- Kerner states that the physiological action of the oxidized product is much weaker than that of quinine. Chi- tenine is formed by action of permanganate on Cjuinine, is insolu- ble in ether, fluoresces, and gives the thalleioquin reaction. ('. — ^iiluhilitv'n. — Quinine is sparingly soluble in water; quite freely soluble in alcohol, ether, chloroform, amyl alcohol ; mode- rately soluble in water of ammonia, benzene, glycerine ; and sparingly soluble in petroleum benzin. The alkaloid triltyilrate is soluble in 1H70 parts water at 15° C (Hesse), in 1438 parts water at 20° C. (Sestini, 1867), in 760 parts boiling water (IIeg- NAULn, 1S75), in 902 parts boiling water (Sestini), in six parts of ordinary alcohol at 15° C, in lyV parts absolute alcohol (Eeg- nauld), in 2 parts boiling alcohol of 90^, in " about 25 parts of ether " (U. S. Ph.), in 22| parts of ether at 15° C. (Regnauld), in " about 5 parts of chloroform " (U. S. Ph.) The anhydrous alkaloid is soluble in 196(1 parts of water at 15° C. (Hesse), in about the same proportion of ether required for the hydrate (PIesse), in (near) 2 parts chloroform (Pettenkofer, 1858), in 200 parts benzene at 15° C. or 30 parts boiling benzene (Oude- mans, 1874). Crystals, mostly needle-form, can be obtained from nearly all solutions. From benzene, crystals of C2oIl24]Sr202-|-CeH6 ^^^ obtained (Oudemans). Solubility in ether is diminished by pre- sence of other cinchona alkaloids (Paul, 1877). Quinine has a decided alkaline reaction, promptly shown upon test-papers in tlie aqueous solution. The normal salts of the stronger acids are neutral to litmus, the sulpliate of manufacture notinfrequently alkaline in the least perceptible degree. — Quinine salts of ordinary acids are soluble or moderately soluble in water and in alcohol, except the sulphate, which is only sparingly soluble QUININE. 129 in water. The proportion of wuter rcvpiired for tlie free alkaloid at 100° C. is about that recpiirtMi for the sulphate ;it 15° C. SoluhU'ii'iex of qu'inhu Hulti^. — Quinine xulpliate^ (G,uH„^NoO._>),.H.S()^.T1IJ)=s7l', is soluble "in 71-0 parts of water and in (i.") parts of alcohol at 15" C (51t°F.); in about 30 parts uf boiling water, in about 3 parts of l)oiling alcohol, in small proportions of acidulated watei-, in -to parts of glycerine, in lOOK parts of chloroform, and very slightly soluble in ether" (U. IS. Pli.) Its solul)i]ity in water is decreased by presence of am- monium sulphate (Cakles) or sodium sulphate (Sculickum, 1SS5) ; in chloroform is increased by presence of cinchonine or quinidine sulphate. From acidulous acpieous solution it is sparingly dis- solved by amyl alcohol (Baefoed). In alcoholic solution it is pre- cipitated l)y adding ether. — Quinine hixnljilnde^ C2oH,,^No< )o 112804.711.10 = 548, is soluble "in about 10 parts of water (with vivid blue fluorescence) and in ?j1 parts of alcohol, at 15° C'. (59° F.) ; very soluble in boiling water and in boiling alcohol "' (U. S. Ph.) It has a strongly acid reaction. — The doubly acid sulphate, C._>QlL,4^.>0o(Ii.^lSf >^).JIIoO, is freely soluble in water and in alcohol. — Quinine Iii/(h'mi ])arts of alcohol, at 15° C (59" F.) ; in 1 ]xirt of boiling A\'ater and very soluble in boiling alcohol; when rendered anhydrous it is soluble in 1 part of chloroform " (U. I>. Ph.) In 9 parts of chloroform (Hager's " f'ommentar" ). — JSTormal quinine Jiijd rioiliile, instable, is more soluble than the sulphate. — Quinine valerinnute, 0._,||ll,_,j^NoO,, r'-HjQO.^.IIgO^Wl, is soluble in about 100 parts of water ami in' 5 parts of alcohol, at 15° C. (5!»' F.), . . and slightly soluble in ether" (U. S. Ph.) — Quinine tunnate^ amorphous, is but very little solulile in cold water (nearly tasteless), but is soluble in alcohol and slightly soluble in ether, and by long digestion with water is converted into soluble (piinine gallate (Lintner). — Qui- trine tartrate, normal {V.,j^\\.,^}\.f ).,).,(' ^\\^.()^..ll.p, is soluble in 910 parts of water at 10°(;., ninch more soluble in hot water and in alcohol (Messe, 1sG5).- (^^//y///^- a/Y//rt/'(% ((V,iIL„N.^< ),,)., ' JoBST,1878. Fluckiger's"Ph!ir. rhemie,"42.'). IIukit'.s " Phiii. Praxis," iii. 291. Produced of very variable I'oiripositioii and properties. Ascribed ronnula, CjoHj,N502(OnH,oO[,)s=25 per ceiil. (juinine. Jobst prepared it, 31 percent, quinine; and found it in oommeroo from 7 per cent, to 22 per cent, quinine. 130 CINCHONA ALKALOIDS. H2C0O4 . 6H2O, requires 898 parts of water at 10° C. for solu- tion •' 1446 parts at 18° C. (Shimoyama, 1885). d. — Fluorescence. — -In general, quinine salts with inorganic acids containing oxygen exliibit blue iiuorescence in their aqueous solutions. The hydracids of chlorine, bromine, etc., the cyanogen hydracids, and thiosulphuric acid, in union with quinine, do not give fluorescence. By adding sulphuric acid the fluorescence is obtained with all the salts in aqueous solution. But the hydra- cids, if present, in proportion to their quantity diminish the reac- tion. Alcoholic solutions show little fluorescence ; solutions in ether, chloroform, etc., none at all. The bisulphate fluoresces much more strongly than the normal sulphate, in solutions of equal strength, and the fluorescence of a neutral solution of the sulphate is much intensifled by acidulating with sulphuric acid. — To obtain the full delicacy of the reaction, put the solution in a test-tube or beaker of such width that a depth of at least two inches is obtained. Place over a black ground, in a strong light falling horizontally from one direction, observing from above, comparing with a like column of distilled water, and, if neces- sary^, shading the eye from the direct light and shading the liqiiid from tlie lateral light. Greater intensity is attained by throwing the light from a lens in a pencil upon the liquid.' So observed, 0.0000.5 gram quinine, in 5 c.c. acidulous solution, gives distinct fluorescence, and this (1 in lOOOdd) is not the limit of dilution (Baefoed, 1881). — The fluorescence of quinine is shared by qui- nidine, and by diquinicine, hydroquinine, hydroquinidine ; not by einchonidine nor by quinicine. ThaJleiaqidn lest. — Treated in a white porcelain dish with fresh chlorine-water or bromine-water, not in too great excess, or well diluted, and tlien with ammonia to just efiiect an alka- line reaction, a solution of quinine gives a green precipitate, thalleioquin, dissolving to a green solution by adding a further excess of ammonia. In more dilute sohitions a precipitate is not obtained at all, but a green liquid. Bromine gives with dilute solutions a better result than chlorine (Zellee, 1880); an exces- sive action of either is to be avoided. According to Baefoed a fine reaction is given by 0.001 gram of quinine, in 5 c.c. of water acidulated with sulphuric acid, treated with 10 drops of very weak bromine -water or of fresh chlorine- water, and then with 2 drops of ammonia-water: but with 0.0005 gram, in 5 c.c, 2 drops 'For more minute examination see Stokes, 1853; H. Morton, 1871; " Watts's Diet.," 3, 634; 8, 1193. QUININE. 131 weak bromine water and i drop auinionia- water, the limit ia reached. Trimble (1^77) has iisetl the reaction for a colorome- tric method, and prepared a standard green sohition by propor- tions of 0.01 quinine or quinine salt in 5 c.c. of fresh clilorine- water, adding 10 c.c. of ammonia-water and diluting to l(l() c.c. — If the green ammoniacal solution be just neutralized with acid a blue tint is obtained, and, by acidulating, a violet to red colo returning to green again when ammonia is added in excess. If ferricyanide of potassium l)e added after tlic chlorine or bro- mine addition as above, and then ammonia barely enough for an alkaline reaction, a red color is obtained. Froehde's reagent, witii dry quinine, gives a slight green color (Deageneoeff). — The thalleioquin test of quinine is shared by quinidine, diquini- cine, and quinicine, also by hydroquinine and hydroquinidine, but not by cinciionidine nor cinehonine. The alkali hydrates precipitate quinine from solutions of its salts, the precipitate becoming slowly crystalline (^ee «), and being quite readily soluble in excess of ammonia, and some what soluble in excess of ammonium carbonate, not of tlie tixed alkali hydrates, or only very slightly by potassa. Tartaric acid pre- vents tlie precipitation in solutions more dilute than about 1 to 300 ; and ammonium chloride increases the solubility of the pre- cipitate. — In free ammonia the quinidine and cinclmnidine pre- cipitates are less soluljle than that of quinine, and tlie cinehonine precipitate is but very sliglitly soluble. The alkali carbonates, and, more slowly, the bicarbonates, precipitate quinine, insoluble or, witli bicarbonates, but sliglitly solul)le in excess. Htritpii.th'de test. — tierapathite (Heeapath, 18.")2) is one of the iodosulphates of quinine. Its formula (Joegensen, 1876) is ((:..,f,K.,^^,p.,)J\LjAO^.JJll)J^. ( \U )\. Dried at 100° C , it contains i'>'>. *)')'> per cent, anhydrous quinine. It crystallizes in plates, either rectangular or rhombic, of six or eiglit sides By reflected light the crystals are very lustrous, or iridescent emerald- green ; by transmitted ligiit they are dichroic, in the direction of one axis nearly transparent, but wlien certiiin axes are super- imposed they are nearly opaque. A play of dark and light siiades is obtained with crystals of microscopic size floating in a drop of liquid undeii tlie cover-glass. The large crystals ha\'e the optical powers of tourmalines, but in greater intensity. Ilerajiathite is at first nearly insoluble in cold water and soluble in lOOO ])arts hot water, but is decomposed by water with formation ol' quinine bisulphate and hydriodide. It dissolves in 50 parts boiling alco- hol of 85fc by weight; in 650 parts of cold alcohol of same 132 CINCHONA ALKALOIDS. strength. In 800 parts of OOf^ alcohol at 10° C. (Joegensen). In 751 parts of U2,'^ alcohol at 24.:.° C. (76.1° F.) (De Yeij, 1875). It is always crystallized from alcohol, usually acidulated. The large crystals of herapathite can he mechanically separated from amorphous precipitate of other cinchona alkaloids. Db A"i;i.t states (1SS2) that the best reagent for the quali- tati\'e recognition of crystallizable quinine, when in a mixture of cinchona alkaloids, is the iodosulphate of chinoidine, pre- pared as directed (under f ) for quantitative uses. This is added to a solution of 1 part of cinchona alkaloids dissolved in 20 parts of 92-05;^ alcohol acidulated with 1.5^ of sulphuric acid, this solution being then diluted with 50 parts of alcohol. The iodosulphate reagent is added (before heating) so long as a dark brown-red precipitate is formed, when, with slight excess of reagent, the licjuid accpiires a yellow color. The mixture is now heated to boiling, to dissolve the precipitate, then set aside for crystallization of the herapathite. Barfoed (1881) dissolves alka- loid supposed to contain 0.01 gram quinine in 20 drops, or 0.01 gram quinine sulphate in 10 drops, of a mixture of 25 drops of alcohol, 30 drops of acetic acid, and 1 dnip of diluted sulphuric acid, lieating to boiling, and then adding 2 drops of alcoholic solution of iodine (1 to 200) and setting aside. Crystallization may begin in 15 to 30 minutes. Excess of iodine tends to produce otlier iodosulphates of quinine. Joegensen (1876) describes three classes of these : (C.oII.,,N„0„),(II.S()j3(HI)J° ((j;oii:^NoO„)o(ii;s(jj (111)21° (c;oH:,Js-:( y^li n:soj (HI)oP Olive-gray, bronze, brown, blue, and black colors are found, as well as green shades; and needles, as well as plates. The results are governed mainly by the proportions of quinine, io- dine, and sulphuric acid taken. TJie other cirieli parts of alcohol of '.yi to '.t.j per cent, on a water-bath, and is thus dissolved, and the solution allowed to cool. In Cooling, a part of the dissolved substance is separated. The clear dark brown-red colored solution is evaporated on a water-bath, and the residue dissolved in 5 parts of cold alco- hol. This second solution leaves a small part of insoluble sub- stance. The clear dark brown-red colored solution olitaineil by the separation of this insoluljle matter, either by decantation or filtration, constitutes the reatjent which, under the name of " iodo- sulphate of chinoidine," L)r. De \^ri] uses both for qualitative and quantitative determination of the crystallizable (juinine in barks. The formniion of herapath'ii<\ in the estimation, is directed by De A'rij as follows : Of the mixed alkaloids from a cinchona bark, 1 part (1 gram licing sufficient) is dissolved in 2n parts of alcohol of 92 to '..t5 per cent., containing 1.5 per cent, of sulphuric acid (of which an excess above that for production of acid sul- phates is avoided). The resulting alcoholic solution of the acid sulphates of the alkaloids is then diluted with .■")(> parts of pure alcohol. From the dilute solution so obtained tlie quinine is preoipitated at the ord'nianj tciiijicfufiire by adding cai-efully, by means of a pipette, the above-mentioned solution of iodosul- phate of chinoidine as long as a dark brown-i-ed precipitate of iodosulphate of quinine (herapathite) is formed. As soon as all the quinine has been precipitated, and a slight excess of the re- 138 CINCHONA ALKALOIDS. agent lias been added, the liquor acquires an intense yellow color." Tlie beaker containing the liquor with the precipitate is now covered by a watch-glass, and heated till the liquid begins to boil and all the precipitate is dissolved. The beaker is then left to itself, and in cooling the herapatliite is separated in the well- known beautiful crystals. After twelve hours' rest [finally at 16° C] the beaker is weighed to ascertain the amount of liquid which is necessary in order to be able to apply later the neces- sary correction; for although the quinine-herapathite is very slightly soluble in cold alcohol, it is not insoluble (c?, p. 131). It is ascertained with a suiall portion of the solution that enough reagent has been added, when the clear liquid is poured off, as far as possible, on a filter, leaving the majority of the crystals in the beaker, which is now weighed again to ascertain the amount of liquid, which is noted down. The crystals are now dissolved to recrystallize, for removal of traces of adhering cinchonidine iodosulphate, as follows : The crystals on the filter are washed into the beaker with a little of the alcohol, and all the crystals dissolved in just enough alcohol at the boiling point. After perfect cooling [and standing at 16° C] the weight of the beaker is taken, the crystals carefully collected on a small filter, and the empty beaker weighed again. The difEerenee in weight will indicate the amount of liquor, which is added to that of the first liquor. The sum of the weights of the li- quor X 0- 00125 ^ correction for solubility of the herapatliite, provided the crystallization has been completed at 16° C." The herapathite crystals on the filter are thoroughly washed with a saturated alcoholic solution of pure herapatliite.'' The washed crystals are drained, with tapping of the side of the funnel, the filter taken out and quickly pressed between blotting-papers, and as soon as air-dry the crystals are transferred from the filter to a fitted pair of watch-glasses, and dried on the water-bath (or at 100° C.) to a constant weight, avoiding the access of air. To the weight is added tlie correction for solubility, to obtain the total quinine iodosulphate, (02011241^202)4(112^04)3(1-11)314 (d, 'If cinchonidine be present in large quantity, the author states that the due control of this slight excess of the reagent reqiiires a great deal of practical experience, and must be studied on a solution of cinchonidine itself, taken in the proportions above directed. - If another temperature has been employed, the solubility of the hera- pathite is to be determined by experiment at such temperature. In this the herapathite can be estimated by volumetric hyposulphite: 21.58 parts of iodine representing 100 parts of herapathite. » A washing-bottle containing an excess of pure crystallized herapathite in 95 per cent, alcohol may be kept ready for application. QUININE. 139 p. 132), of which one part contains 0.55055 part of anhydrous quinine. g- — Tests for h/ij>urit/es anil deficiencies. — The impurities or deficiencies of (quinine salts to be generally regarded are, in or- der of importance, (1) other cinchona alkaloids in excess of a proper limit, and (^2) an excess or deficiency of moisture or water of crystalHzation, causing variableness of strength. Quinine manufacture is mainly conducted by a small number of houses of well-known standing, and the product is carried in well-regu- lated commercial chrainels, so. that it is but little exposed to the introduction of falsifications. The one cinchona alkaloid, not quinine, most difficult for the manufacturer to remove and for the analyst to estimate, and actually present in largest jiroportion in the product from barks in genei'al, is cinchonidine. In the pro- duct of the "cuprea" barks, however, anothei' alkaloid is intro- duced, which is cupreine, or the conjugated c<)in])ound of cupreine with quinine known as homoquinine, and it becomes ncc( ssary to give general attention to the possible presence of this alkaloid. Tlie /'ecoijnized tests for other cinchona alkaloids depend, in principal, upon (!) the removal of quinine as a ci-ystallized sul- phate (Keener, 1802), (2) the separation of the free alkidoids by ether (Liebig's test), or (o) by excess of iimnujiiia (Kekkee, 1S<'!2), which is used also in all tests to liberate the alkuloids from their salts. Hesse's test (l,s79) depends upon }iiinci])lcs (1) and (2), as also does Paul's (ls7T), while Kerner's test depends upon (1) and (3). Keniers test of Quinine tSuIji/icite provides a uniform arbi- trary measure, by certain fixed conditions, as follows : Quinine as a sulphate is macerated with water; the quantity of the water is 10 parts for 1 part of crystallized sulphate ; at whatever tempera- ture the maceration is commenced, it is invariably ctmcluded at the temperature of 15° C, when the mixture is at once filtered ; and of the filtrate 5 c.c. (for some purposes 10 c.c.) are ti-cated with an accurately measured volume of ammonia-water of exact- ly known strength (s.g. <».'.i2n or 0.960) until a clear liquid is ob- tained, the ammonia- water being mixed at once with the filtrate by gently inclining or rotating tlie test-tube while this is closed with the finger. — With a small and not bibulous filter 1 gram of crystallized sulphate with 10 c.c. of water will easily yiehl the 5 c.c. of filtrate for one ammonia test. Directions often sjiecify 2 grams of the crystals with 20 c c. of wafer ; and for (juantita- tive titrations it bec(3mes proper fo take 5 grains of the ci-ysfal- lized sulphate with the tenfold number of c.c. of water, to pro- I40 CINCHONA ALKALOIDS. vide for sevei'al parallel aiumonia tests;' but it will be observed that the required quantity of ammonia, the index of the test, is only placed in ratio to the 5 or 10 c.c. of the filtrate [where it acts not wholly independent of variations of atmospheric temperature], and has no ratio to the quantity of quinine sulphate taken. It will be further observed that the fixed proportion of water taken in maceration, 10 parts to 1 of the salt, controls the quantity and concentration of the alkaloids not quinine. The 10 parts of water at 15° 0. would dissolve 0.1 part of cinchonidine, 10^ of the quinine sulphate taken, and a smaller quantity of water would in most cases dissolve the entire (juantity of alkaloids not quinine, but it is of importance that the solution of these alka- loids shall be made up to the same volume in every trial of the test. The quinine sulphate is in excess of saturation of this salt; indeed, one-fiftieth as much quinine salt would suffice to more than saturate the 10 parts of water. — In Kerner's method the Quinine Su/p/ntfe is readily recovered in purified form, almost without waste, and sometimes with gain, of vahie. Of the real quinine sulphate 99.S(j<^ remains on the filter as Eecrystallized Sulphate of Quinine. It is dried by pressing gently between l)lotting-papers and setting aside in dry air, avoiding efflorescence. Tlie (|uiiiine dissolved by the ammonia crystallizes on evapora- tion of the latter, and this separation has been adopted in puri- fying small (|uantities of quinine. Foj' 5t^(^ of aqueous solution saturcoted at 15° G. the volumes of aminonia--uyi.ter of sp. gr. 0.92 (21.7$^ ^Hg), and of sp. gr. 0.90 {lOfo NII3), required to give a clear solution, are as follows (Kekxek, 1SS(>=): ' Hager arranges for special tests, in different portions of the filtrate, for single cinchona alkaloids, but of tliese special tests the only trusty one is that for quinidine, rarely present — a test made with 5 c.c. of the filtrate by adding 5 drops of a 1 to 30 solution of potassium iodide, stirring, and setting aside for crystallization of f|uinidine hydriodide. ^Archil' d. Flmr.. [3], 17, 444. In these experiments with alkaloids other than quinine they were sometimes added (in known quantity of their sulphates) to the 5 c.c. of the filtrate from pure quinine sulphate, but in case of cinchoni- dine it was mixed with the crystallized pure quinine sulphate for one series of trials, and in certain of the tests there was maceration with water at 60° and at 80° C. before the crystallization at 15° C. These varied conditions made little difference with the results. But when the quinine and cinchonidine sulphates have been crystallized together, previous hot digestion increases the efficiency of the separation. See Yungfleisch, 1887: Phar. Jour. Trans. [3] 17, 585; Jour, de Pharni. [5] 25, 5. The same is staled in general terms by Paul 1877: Phar. Jour. Trans. [3] 7, 654. 'J'he author is indebted to B. A. Ruddiman for determinations of difference due to previous hot digestion, a report of which will soon be presented for publication. QUININE. 141 With pure Quinine Sulphate For 0.001 -nun C'in- chonidine sul- phate added .... For each per ceut. of Cinchonidine sulphate For 0.001 i;-rani Quinidiue sul- phate For 1 per cent. Qui- nidiue sulphate. . For o.OOl gram Ciuehonine sul- phate •' For 1 per cent. C'inchonine sul pliate Ammonia ofs.g.0. 960. .").0 to 5.1! c.c. Additional to abore. 0.4:0 c.c. toO.li c.c. 2.0 c.c. to 2.2 c.c. l.l(jc.c.tol.3ic.c. 5.8 c.c. to 6.7 c.c. 0.62 c.c. to 0.80 c.c. 3.1 c.c. to 4.0 c.c. Ammonia of s.g. 0.920.' 3.0 to 3.3 c.c. Additional to above. 0. 28 to 0.35 (««. 0.32) C.c. 1.4 to 1.7 (m). 1.6) C.c. 0.56 c.c. to 0.78 c.c. 2.8 c.c. to 3.9. c.c. 0.36 c.c. to 0.40 c.c. 1.8 c.c. to 2.0 c.c. Kerner's test, in the pharniacopunal form, merely determines whether the article tested does or dues not reach a certain recog- nized limit of impurity ; but, as applied by the analyst, the am- monia-water should be added from the burette and the required number of c.c. should be noted, as an index of the degree of impurity, whether aliove or beluw the legal standard. The number of c.e. of ammonia-water (of pharmacopoeial strength and under pliarmacopceial conditions) is in itself a certain measure of value, already having a meaning to <]ealers and consumers, irresjjeetive of interpretations in ])er cent, of cinchonidine or ' Experiments by Mr. E. A. Ruddi.ma.v, made in n,n investigation now in progress in ttie University of Jliohigan, indicate that of ammonia water of s. g. 0.960 there are required only 1.5 times more than of the water of s. g. 0.930, though the latter is 2.2 times stronger than the former. Averages of ton titra- tions, for each degree Ijelweim 15" and 25' C, agreed nearly with this ratio of 1.5 to i.n. '•' In respfi't to rinchonine (in presence of much quinine) these data arc sur- prising. Taken se|)arately, each in a cold-saturated suljihafc snhitinn (15" C), Kerner in ls(!2 found tlie quantities of ammonia used to redissolve the alkaloid from 1 c.c. of the filtrate as follows: Of ammonia-water of s.g. O.ltfiO, lor qui- nine, 1.3 c.c. ; for cinchonidine, 10 c.c. ; for ([uinidine (h Quinidine). 15 c.c. ; for cinchonine, over 300 c.c. — The experiments made by Mr. Teeter (l^niv. Mich., 1880: New JO'vi., 9, 258) in defining the limits of the test of quinine sulphate only show that in the preponderating presence of quinine both quinidine and cinchonine require more ammonia than cinchonidine does. 142 CINCHONA ALKALOIDS. other alkaloids. The ammonia measure, based upon fixed condi. tions of application, may be adopted over the world as a simple expression of comparative value. Against this preference for the ammonia measure it can hardly be urged that there is dis- agreement as to how many per cent, of cinchonidine are ad- mitted under 7 c.c. or e by rubbing the salt with about 100 times its weight of water in a mortar, rinsing into a glass-stop pered bottle,^ and digesting along with the commercial quinine sulphate to be estimated, in the same conditions of temperature and time, as directed below. — "Water of Ammonia of sp. gr. 0.920 of ordinary quality is all that is required as a reagent.— In the titration 5 grams of the sulphate of quinine to be tested are rubbed in a mortar with distilled water enough, so that -when all is rinsed into a glass-stoppered bottle it shall just reach a mark of 50 c.c. volume. This bottle and the bottle containing the standard quinine sulphate solution are now set in the same ves- sel of cold water, at as near 15° C. as convenient, and left, with occasional careful shaking, for 12 to 18 hours. Or both bottles are warmed in the same vessel of water at near 100° 0. for some time, shaking several times, and then set together in a vessel of cold water for an hour or more. The bottle containing the am- monia is placed in the same cold water, so that at the end of the 1 Keener, 1862. , Impi'oved in 1880: ArrMv d. PAar., [3], i6, 186-285; 17, 438-454; Jour. Chem. Soc, 40, 63; New Rem., 10, 168. '' The standard quinine solution sliould be strictly neutral in reaction. If acidulous, it is to be brought back to the neutral point by adding to it, with agitation, just sufficient of quinine hydrate, freshly precipitated from the same solution and well washed. — A. B. P. QUININE. 143 dio;estioii it shall have the same temperature. The two quinine solutions are now tiltered through two dry iilters,' at the ordi- nary atmospheric temperature (which is i)referably near that of the digestion), obtaining from the standard quinine solution the same volume of filtrate furnished by the other solution (40 c.c. or over). 10 c.c. of each of these solutions is taken, by a good pipette, in a test-tube for titration. The ammonia is added from a burette, vehich is better if it be long, and narrow enough to register in ^ c.c. At first 5 c.c. of the ammonia are run in, the test-tube closed by the finger and given two or three circular motions to mix the liquid without shaking, and further smaller additions made, 0.3, 0.3, 0.1 c.c, and by drops, with the circular agitation after each addition, until the liquid becomes perfectly clear. Toward the last it is well to wait 5 to 10 seconds after each agitation before the next addition. The end reaction is complete clearing. Then at once the standard quinine solution is titrated in the same way, taking a fresh portion of ammonia in the burette. The 10 c.c. will suffice for four titrations of each quinine solution, from which the average can be taken. — ■ Each o.;12 c.c. (or 0.3, round number, the extremes being 0.28 and 0.3.5 c.c.) of the excess of the ammonia required for t4ie qui- nine under test (beyond that required for the standard quinine) indicates 0.001 gram of cinchonidine sulphate. This 0.001 gram of cinchonidine sulphate is estimated upon the commercial qui- nine salt represented by the (10 c.c.) portion of filtrate taken, or (havin:;- taken lO c.c. of a 1 : 10 solution) each 0.32 c.c. of 0.920 ammonia (beyond that taken for the standard sulphate) indi- cates 0.1 per cent, of the cinchonidine impurity. Should the percentage of cinchonidine be over 1.5, or at most 2.0, the results become inaccurate, owing to the gelatinizing of the precipitated alkaloid. In this case 10 c.c. of the filtrate under estimation may be diluted, by addition of standard quinine filtrate (of parallel digestion), to 20, 30, or 40 c.c, and portions of lo c.c. of this diluted filtrate titrated. Then, after deduct- ing the average cc of ammonia taken by 10 c.c. of standard quinine, the remaining c.c. are multiplied by 2, or 3, or 4, when each (».32 c.c. = 0.1^ cinchonidine, as before. The errors are stated not to exceed 0.05 per cent, of the connnercial (piinine salt. 'The crystalline residues in (he filters are to be saved, as purified sulphate of quinine, drying them by pressing th(! filters between blotting-papers, etc. It will be observed that the residue from filtration of the " standard quinine siilfihate" solution is "standard quinine sulphate" prepared with an addi- (i'n.il |iurification. c44 CINCHONA ALKALOIDS. An apiyroxlinate volumetric estimation is made in a short operation, according to Kerner (where last quoted), as follows : The quinine salt to be tested is macerated with ten times its weight of water at 15° C, 5 c.c. of the filtrate is taken in a test- glass of 10 c.c. capacity graduated in 0.1 c.c, 3 c.c. of water of ammonia of sp. gr. 0.920 are added and intermixed by gentle circular agitation of the test-glass while covered by the finger, and additions further made, at last by droj)s, until a clear liquid is attained, when the total volume is read and the volume of added ammonia is noted. — The required addition of only 3.0 to 3.3 c.c. of the ammonia-water would indicate absence of cincho- nidine sulphate; use of 5 c.c. ammonia (0.920) indicates near 1 per cent, cinchonidine sulphate ; and these data serve to show approximately the indication ' (Kerner). The U. IS. Ph. (ISSO) directions for Kerner^s test are as fol- lows: '• The residue of 1 gram of (crystallized) sulphate of qui- nine, dried to a constant weiglit at 100° C. for estimation of water, is agitated with lt> c.c. of distilled water, the mixture macerated at 15° C. (59° F.) for half an hour, then filtered through a suaall filter, 5 c.c. of the filtrate taken in a test-tube, and 7 c.c. of water of ammonia (sp. gr. 0.960) then added; enclosing the test-tube with the finger, and gently turning it until the ammonia is fully intermixed, a clear liquid should b3 obtained, if the temperature of maceration has been 16° C. (60.8° F.), 7.5 c.c. of the water of ammonia may be added ; if 17° C. (62. 6° F.), 8 c.c' may be added. In each instance a clear liquid indicates the ab- sence of more than about 1 per cent, of cinchonidine ' or quini- dine, and of more than traces of cinchonine." The Ph Germ. (1882) dlreeiions are these : 2 grams of quinine sulphate are agitated with 20 c.c. of water at 15° 0., and after half an hour filtered. To 5 c.c. in a test-tube am- monia [0.960] is added until the precijDitated quinine is again dissolved. The required quantity of ammonia should not overgo 7 c.c. The Ph. Fran. (1881) directs the 2 grams quinine sulphate ' By a more minute calculation, if the ammonia-water hold its strength, each 0.33 c.c. added above about 3.3 c.c. indicates 0.2 per cent, of cinchonidine; so that 1 per cent, of cinchonidine is indicated by 4,9 o.o. (total addition), and 3 per cent, by 6.5 c.c. But exactness is not to be assumed without the help of the control analysis. — A. B. P. "Differences of 0.5° C, Kerner states, do not sensibly ailect the result. '' These official allowances for temperature are more liberal than Kerner's results wouhl justify. 'Sep the table from Kerner's figures, p. 141, according to which (at 15° C.) from 7.0 to 7.5 c.c are required for 1 per cent, of cinchonidine sulphate. QUININE. 145 in 20 c.c. of wiiter to hu digested hot for half an hour, then maintained at \y'C. by immersion in a bath of water of tins temperature for inilf an hour with freciuent agitation, and filtered. Of the filtrate, 5 e.e. are treated with 7 c.e of ammonia-water of O.GtJO sp. gr., when a precipitate after gentle intermixture, or a turbidity or crystalline deposit formed after i!4 hours, indicates an unacceptable proportion of alkaloids other than quinine. Auotlier portion of 5 c.c. is evaporated in a tared capsule to a weiglit constant at 10U° C, when the weight of the residue should not exceed 0.015 gram.' Tcinj>cnit(nr of the Filtrate in the reaction of tlie ammonia. ■ — Hitherto the infiuence of temperature has lieen regarded only as atfecting the solubility of the sulphate of quinine, and the concentration of this salt in the filtrate. The temperature of digestion has been regulated, while that of the filtrate and the ammonia-water has l)een left to vary with the Avarmth of the atmosphere. ^ From experiments recently made by Mr. E. A. Ruddiman, in tlie laboratory in which the author is engaged, it appears that the temperature of the filtrate under addition of the ammonia is influential. With digestion and filtration at 15° C, the warmer the filtrate becomes, the less ammonia is required to redissolve the quinine. For each 1° C. increase of temperature in the titration, an average of 0.1-f S c.c. less of ammonia of sp. gr. 0.920 is required to redissolve the quinine. This average was drawn from over ten titrations for each degree between 14° C. and 2t!° (_'., the temperature of the filtrate being taken at the end of the titration, the filtration itself being always held M'ith tlie digestion at 15° C. The extremes were 0.1 and 0.2 c.c, for 1° C. — -in volumetric estimation by comparison with standard quinine sulphate, this influence of temperature of titration of the quinine will be the same in each of the parallel opei-ations, and there- fore will not vitiate the conclusion. But in the pharmactipreial tests, differences of titration temperature must afi'ect the result, in part counteracting like differences of temperatirre in the digestion.- — The effects of titration temperature upon the cin- chonidine, cinchonine, and quinidine are questions under in- vestigation. In 1S84 Mr. IIenky B. Paesons' reported the application of the IT. S. Ph. form of the test to 1033 samples of quinine sul- ' The residue of pure quinine sulphate would be 0.00675, leaving 0.00825 tn consist of other alkaloids or impurities — a quantity constituting about 1.6 per cent, of the commercial quinine sulphate tested. ' " The Practicability of Kerner's Test ": Proc. Am. Phar., 32, 458. 146 CINCHONA ALKALOIDS. phate, embracing 5 brands, of American, German, and Italian production, as follows : Brand. No. samples. Average c.c. Am. Over 7 e.c. Am. ISTo. 1. American. 16 9.5 16 " 2. " 217 5.7 1 " 3. German. 11 6.1 none " 4. " 627 6.0 7 " 5. Italian. 162 6.8 35 Total, 1033 6.1 c.c. m. 59 (rejected). Mr. Parsons states that ' ' if the sample of quinine sulphate be dried before testing, as the IT. S. Ph. directs, the amount of am- monia-water required to produce a clear solution is generally, but not always, about 0.5 c.c. greater than where the same sample is not dried before testing." Also, "the test is liable to mislead unless every detailed precaution is observed." — In 1884 B. F. Davenpoet, as State Analyst of Drugs in Massachusetts,' ex- amined 28 samples, from seven makers, using the official form of Kerner's test, and found 28 per cent, of the samples to fall below the U. S. Ph. requirement. 77ie application of the Ammonia Test to Quinine Com- pounds other than the Sulphate requires their convei'sion into sulphate."" — This may be done, in an exact application of the test to salts of quinine^ other than sulphates, very easily as follows : A weighed quantity, ''irom 2 to 5 grams, of the salt is dissolved in about fifty times iis weight or a sufficient quantity of water, tlie alkaloids completely precipitated with sodium hydrate solu- tion, the precipitate washed until the washings give but little cloudiness with magnesium salt solution, and the washed preci- pitate rinsed tlirough a perforation in the filter-point into a test- glass, graduated in -J c.c. and measuring 20 to 50 c.c, tilling to near the volume specified below. The mixture is heated for five minutes by immersing the test-glass in nearly boiling water, 1 " Fifth Ann. Report Mass. State Board of Health,'' etc., Boston, 1884, p. 161. '' In his first paper, in 1863, Kerner proposed to apply the ammonia test directly to salts not sulphate, directing the solution of the salt to be diluted to the limit of solubility of quinine sulphate (Zeitsch. anal. Chem., i, 161). The later report (1880) does not reach the application to other salts. 2 To find, for any salt of quinine, the volume equal to 10 c.c. for each gram of crystallized normal sulphate producible from 1 gram of said salt: Comh.no. of salt taken (in equation to form. 1 raol. sulphate) : 872 : : 10 : »= c.c. de- sired. QUININE. 14; and dilute sulpliuric acid is added to maintain a slight acid re- action to litmus-paper during the digestion. Tlie mixture is now exactly neutralized to litmus-paper by adding dilute am- monia-water, ilic volume of the whole made up to a number of c.c. fijual to 11.5 times the number of grams of quinine hydrochloride taken, 10.3 " " " hydrobromide " 9.S " " " valerianate '" wiien the mixture is placed for half an hour or longer in a bucket of water at 15° C. (59° F.), and filtered through a small filter. One or more portions of 5 c.c. are tested with ammonia-water, as in the pharmacopojial form of the test (see page 144), and the result judged for the salt taken, on the basis of quinine sulphate. Or, cooling parallel with " standard (juinine suljjhate" solution, for titration, as directed on p. 142, portions of 10 c c. are titrated in comparison with " standard quinine," fur percentage of cinclio- nidine, etc. The results will count, on the basis of tlie 5 c.c. or of the lU c.c. of hltrate used, in per cent, of the salt of quinine taken. That is, each 0.32 c.c. of ammonia of sp. gr. 0.'.i2(i used for 1(1 c.c. nf filtrate (l)eyond that used for the "standard quinine'') indicatc^ If the bisulphate be neutralized with its own alkaloid obtained from a. divided portion of the salt weighed and taken, the ratio is the same. « ••Liehig's Test."— 'The author is unable to cite published directions of Liebig for the test which has gone under his name for fully thirty years. The test, in a simple form, with far too large proportions of ether and ammonia, is very clearly given in 1833, on tlie sole authorship of Kindt, as follows (Berze- liui^'s Jahnsbericht, 12 (1833), 218; from Brande's Archiv, 36, 2.54): "Kindt hat folgende Methode zur BuUlekkung der (iegenwart von Schwefelsaurem Cinchonin ira Chininsalz ani,'egel)eii. Jlaii zerreibt 1 Gran vom Salze, sehutlet es in ein Probirglas, und giesst 1 Draehrae Aether darauf, womit man es um- schiittelt; alsdann mischt man 1 Urachme Ammoniak zu und sehilttelt wohl urn Wenn sich die Fliissigkeiten wieder scheiden, findet man die belienlungs- hnie rein weiin das salz frei von Cinchonin war, aber die geringste Menge Cin- chonin ira Salz setzsieh deiitlich erkennbar aus der Grenze zwisclien beiden FliisM.'keilen ab." In 1S42 C.vlvert (Jour, de Phar ; Ann. ('hem. Phar 48 24'") undertakes to separate cinchonine bv its in.solubility m calcium chloride solution and in lirae solution, and refers to the use of anmionia, but not to the use of ether, as a solvent of quinine. In 1843 R. Howard {Phar. Jour. Trans. 2 645) savs that cinchonine sulphate is not al all excluded from commercial quinine sulphate -'by any test " which he has " happened to see recommended and he givesa test by weightof crystals from a saturated sulphate solution. In 18.5'^ SoT-Bi.iRAN {Jonr.de Phar., 1S,J2, Jan.; Am Jour. Phar., 24, 166) cites Liebig's authority for the ether test, saying only ■■ Liebig has suggested the detection of cinchonine by treating 15 grains of the salt, with 2 ounces ammonia solution, and 2 ounces of ether, and so on, tlie proportions being nearly those given bv Kindt in 1833, though the quantities are lo times as large. Irom about this time (18.52) the test is commonly mentioned in literature as Liebig s test; but in 1851 or 1852 ZiMMER(.A(/i/-. Ghem.. 1852, 745; (J^tein. (Jazette, 1852, 449) eives the test, with the modern proportions of ether and ol ammonia, witJi- out naming Liebig's authority. Also Henr,(1H47) separates cinchonine by- ether in a complexV"eess, which is cri^cised by Guibourt in ISSl-.-i neither of these authors speaking <.f Liebig. In Gmehn's Cliemistry (Cav. ed. 17. 2,9) the method is entitled "The Quinine Test of Liebig," but among the releiences to as manv as a dozen pnliiished authorities Liebig s name is not found, in hirhXial inquiry i't may further be noted, (hat «hon Likbio -I-t-d the elementary analyses of quinine and cinchonine, m 1831 {Ann. Phys. Uiem., 152 CINCHONA ALKALOIDS. removing tlie excess of the (juinine as a sulphate before separat- ing by ether. The directions of Hesse are as follows : ' A " qui- nometer " is provided, this being a test-tube 10-11 mm. (0.39 to O.-IS inch) wide, and 120 mm. (-t.7 inches) long. The tube is marked at a capacity of 5 c.c, and again at a capacity of 6 c.c. ; the entire capacity of the tube, which is fitted with a cork, being 10 or 12 c.c. Of the quinine sulphate to be tested, 0.5 gram is well sliaken in a test-tube with 10 c.c. of hot water (50° to 60° C), and set aside to cool for ten minutes, shaking with care to prevent the expulsion of the contents. The liquid is now passed through a filter of about 60 mm. (2.4 inches) diameter into the quinome- ter, up to the 5 c.c. mark ; 1 c.c. of ether (sp. gr. 0.724: to 0.728) is added (up to the 6 c.c. mark), and then 5 drops of ammonia- water (sp. gr. 0,96), when the tube is corked and slowly shaken. Gra^ nular crystals appearing within 3 minutes after shaking indicate us much as 3 per cent, of cinchouidine ; at 10 minutes after shak- ing, about 2 per cent, of cinchonidine. After standing 2 hours the appearance under a lens of granular crystals indicates cincho- nidine ; radiating needles, cinchonine or qTiinidine ; no crystals, tlie absence of over 1 per cent, of cinchonidine, or 0.5 per cent, of quinidine, and of over 0.25 per cent, of cinchonine. Absence of crystals after 12 hours shows that less than 1 per cent, of cin- chonidine is present. If now the cork be loosened, and the ether permitted slowly to evaporate, 0.5 per cent, of cinchonidine will leave a distinct crystalline residue. The final residue con- tains amorphous quinine. The test of tSidphate of Quinine for Cinchonidine l)y the Br. Ph., 1885, on the principle of Hesse's test, is much more elaborate than the operation above detailed : " Test for CindbO- Pogg., [3], 21, 25), he specifies the purification of quinine by dissolving it, not in ether, but in ammonia (on the plan of Kerner's test), "as follows: " Der breiartige weisse Niederschlag, welclier durch verdunstes Ammoniak aus der schwefelsauren Auflcisung erhalten worden war, loste sich beini Erhitzen in der etwas freies Ammoniak enthaltenden Plussigkeit vollkommen auf, und gab bei dem abkilhlen ganz Ammoniak freie, sehr feine, glanzende, seidenartige Nadeln von Chinm." ^ Liebig's test was directed by the U. S. Ph. of 1860 and of 1870. in the fol- lowing terms: " When 10 grains of the salt [Sulphate of Quinine] are agitated in a test-tube with 10 minims of officinal water of ammonia [0.960] and 60 grains of ether [0.750], and allowed to rest, the liquid separates into two trans- parent and colorless layers, without any white or crystalline matter at the sur- face of contact." It was generally stated that as much as 10 per cent, of quini- dine sulphate would escape detection by this test. Undoubtedly larger percen- tages both of quinidine and cinchonidine are liable to fail of recognition with the test as commonly applied, '0. Hesse, 1878': Archii' d. P7tar., [3]. 13, 490; Am. Jour. Phar., 51,135; New Rem., 8, 139; Jour. Chem. Soc, 36, 280; Zeilsch. anal. Chem., 19, 247. QUININE. 153 nid'ine and CincJionine. — Heat 100 grains ('r>.4s grams) of the sulphate of qniiiine in live or six ounces (1-1:2-170 c.c.'l of hoilini^ water, with tliree or four drops of diluted 8ul])huric acid. Set the solution aside until cold. Se]);irate, by iiltration, the purified sulphate of quinine which has crystallized out. To the filtrate, which should nearly till a bottle or tlask, add ether, sha'cini;- (jc- casionally, until a distinct hiyer of ether remains undissolved. Add ammonia in very sHglit excess, and shake thoroughly, so that the quinine at lirst precipitated shall be redissolved. Set aside for some hours or during a night. Remove the superna- tent clear ethereal fluid, which should occupy the neck of the vessel, by a pipette. Wash the residual aqueous fluid and any separated crystals of alkaloid with a very little more ether, once or twice. (JoUect the separated alkaloid on a tared filter, wash it with a little ether, dry at 212° F., and weigh. Four jiarts of such alkaloid correspond to five parts of crystallized sulpliate of cinclionidine or of sulphate of cinchonine. •• Ted' for Qniniditu'. — Recrystallize 50 grains (3.240 grams) of the original sulphate of quinine as described in the previous paragraph. To the filtrate add solution of iodide of p(_)tussium, .and a little spirit of wine [alcohol] to pi-event the precipitati(jn of amorphous hydriodides. Collect any separated hydriodide of quin- idine, wash with a little water, dry and weigh. The weight repre- sents about an equal weiglit of crystallized sulphate of (juinidine. '■• Test for (_'iq>reine [i-ee p. 92]. — Shake the recrystullized sulphate of (piinine, obtained in testing the original sulphate of quinine for cinclionidine and cinchonine, with one fluid-ounce (28.4 c.c.) of ether (sp. gr. 0.724-0.728) and a (piarter of an ounce (7.1 c.c.) of solution of ammonia (of 1(K strength), and to this ethereal solution, separated, add the etliereal fluid and wash- ings also obtained in testing the original sulphate for the two alkaloids just mentioned. Sliake this ethereal liquor with a quar- ter of a fluid-ounce (7.1 c.c.) of a ten per cent, solution of caustic soda, adding water if any solid matter separates. Remove the ethereal solution. Wash the aqueous solution with more ether, and remove the ethereal washings. Add diluted sulphuric acid to the aipieous fluid heated to boiling, until tlie soda is_ exactly neutralized. When cold collect any sulphate of cupreine that has crystallized out, on a tared filter, dry, and weigh. •' ' Sulphate of t^uinine ' should not C(jntain much more than five per cent, of sulphates of other cinchona alkaloids." Water of VryKtallizdiion /;/- Hulphitle. of Qiiin.iiie. — IIekki.; ' '1880: Ber. d. chem. Qes., 13, 1517-1520, and elsewhere. 154 CINCHONA ALKALOIDS. has continued to maintain that perfect crystals of pure quinine sulphate have SHgO (16.18^ of water). Keenek' affirms that no quinine sulpliate is manufactured that contains over 14 to an extreme of 14. 6^ of crystallization-water ; above this any con- tained water is free moisture. Also that it is not possible to dry the voluminous quinine sulphate of commerce without some degree of efflorescence. The Ph. Germ. (1882) (without for- mulae) hmits the loss by drying at 100° C. to 15^. The Pli. Fran. (1884) gives 7HoO (=:11.45^) in the formula, and limits the loss at 100° C. to 14.45^^. The Br. Ph. (1885) gives T^HgO in the formula, and limits the loss at 100° C. to this molecular proportion, 14.3,'^. Tlie U. S. Ph. (1880) gives THgO in the for- mula, and limits the loss of weight at 100° C. to 16.18^. Mr. IT. B. Paksons^ reported the loss of water by drying three hours in a (boiling) water-oven, for 1015 samples, of American, Ger- man, and Italian makers, each sample representing 100 ounces, and taken from a can not previously opened. The average of loss of water, for all the samples, was 13.84fc ; for any single manufacturer the lowest average was 12. ei,"?, and the highest average was 14.3(1,'^, The samples of one maker all approached closely to 12 53,'^ (6PIoO). In the report the writer recommends, as others have done, the pharmacopoeial adoption of effloresced quinine sulphate, the two-molecule salt, as a definite and stable form of the alkaloid. QuixiDiNE. The Ciwclmihie of Hesse = 0.011.^:^302=324. In crystals with 21IL3(.) = 396. Chinidine. — Eational Formula, p. 98; Proportion in Cinchona Barks, p. 97. Separation from the Bark, in total alkaloids, p. 102. Separation from Cinchona, •1880: Avchtv d. Phar.. [3], 17, 453. ' 1H84: Proc. Am. Pharm.. 32, 457. ^ The name quinidine, in German "chinidine," was given to the all^aloiil now universally known as cinchonidine, in 1833, by Henry and Delondre. Quinidine vfa,s itself discovered, in ehinoidine, m 1849, by Van Heijningen, who tiien named it i-qninine; again, in commercial ciiiehonine, in 18.il, by Hlasiwetz, who named itcinchotine. In 1853 Pasteuk. believing that he iden- tified Henry and Delondre's iiuinidine among cinchona alkaloids, and discover- ing another which in fact was Henry and Delondre's quinidine, he fixed to this the name cinchonidine, still retained. The name "quinidine" having thus been differently applied, Hesse (1874) proposes to drop it, and use the name "conchinine" for the isomer of quinine. Some of the German writers employ HesseVnomenclatare, but English-writing chemists translate the " conchinine " of Hesse into the English equivalent of German 'chinidine," namely: quini- dine. And this accords with the recommendation of the Quinological Con- gress at Amsterdam in 1877 Fnrther see Kekner's history of this nomen- clature, ISSO: Archie d. Phar., [3], 16 (reprints). The 6-quinidine of Kerner in 1862 is the quinidine of the present time. QUI NI DINE. 155 Alkaloids, index at p. 113. Distinction from other Cinchona Alkaloids, index at p. 100. Microscopic identification, p. 101. Rotatory Power, p. 123. The free alkaloid has been hardly known in commerce, and its snlphate is less used than that of cinchonidine or cinchonine. The chinoidine obtained as a by-product from certain barks is rich in ijuinidine. The eri/stitHuu' forms and heiii /vucti-o/is of quinidine an// its salts are given under a, the sol abilities of the same under c, below. (Quinidine is ideutijied by its fluorescence in the sul- phate and its response to the thalleioquin test id), together with the free solubility of the sulphate in chloroform and its greater solubility in water. Also by precipitation as hydriodide (il). It is sejKirated, by solution of the sulphate in chloroform, or pre- cipitation witli iodide, or otherwise {e); estiriuded, usu.'a\\j by weight of the hydriodide [f). Tests for inqntrities in quini- dine suljilmte are presented under ^, p. 157. a. — Quinidine crystallizes from alcohol, with 3JII.,0, in large, lustrous, iiionoclinic prisms or needles, efflorescent in the air. From ether permanent rhombohedrons with ^\\.,() ui'c obtained; fn.iin boiling water permanent plates with nii.,() (Hkssk). The whole of the water is removed at or below 1-iU" ('., and the dry al- kaloid melts at 1<1S° ( '. It l)eti'ins to brown verv slightly at IfJO" {?,i.\i\i).— Quinidine sidjihate, (('oplI._,^X.,<')o).3lL,S( )^.2ri..( ), crystallizes in white, silky needles or in long, hard prisms, per- manent in the air, giving up the water at 130' (!. — The hisidjditde crystallizes in asbestos-like prisms, with -lIl^.O. — Quinidine hij- droeldnride crystallizes in asbestos-like fibres, with II„(_). — (Qui- nidine ^' ('. (^'AN nER Burg) ; in 70. -I- parts of ether at 10° C. (Deagent)I)i;kk). In chloroform oi- amyl alcohol it is i-eadily solu- ble ; in petroleum ether difficultly soluble. (Quinidine neutral- izes acids in forming noi-mal salts. Qu/iiiidivi' suJjdiute oi a iieutnil I'eac^tioii is soluble "in 100 parts of water and in S parts of alcohol at 15° C. ; in 7 parts of 156 CINCHONA ALKALOIDS. boiling water, and very soluble in boiling alcohol ; also in acidu- lated water and in 20 parts of chloroform, but almost insoluble in ether " (U. S. Ph.) In 19.5 parts chloroform at 15° C, in 9 parts at 63° C. (Hesse, 1879). — Quinidine hydrochloride is solu- ble in 03.5 parts of water at 10° C, and freely soluble in hot water, in alcohol, and in chloroform ; nearly insoluble in ether. — Quinidine hydroiro7nide, anhydrous (Db Yeij, 1875), is siilul)le in 200 parts of water at 14:° C. — Quinidine oxalate, (CooTI.^oK,Oo)on.,C.,04.HoO, dissolves in 150 parts of water at 15° C." d. — In solutions of the sulphates, and especially in solutions acidulated with sulphuric acid, (quinidine exhibits strong blue fiuoremence. (See Quinine, d.) The chloroforiiiiic solution of the sulj>hate has a green fluorescence (Hesse, 1879). — Quinidine responds to the thdleioquiii test (p. 130). Sulphuric acid gives no color ; Froehde's reagent, a greenish color. — Iodide of po- tassium causes in neutral solutions of quinidine salts a crystal- line precipitate of auiuidine hydriodide, CooHo^lSroO^HI, soluble in 1250 parts of water at 15° C. (De Veij). Immediate precipi- tation is obtained only in somewhat concentrated solution, and is incomplete. Full crystallization within the limit of solubility is obtained 1)y warming the mixture and stirring it with a glass rod from time to time as it cools, then leaving some hours at a low temperature, stirring at intervals. The reagent should be neutral, and added in such proportion that the quantity of solid potassium iodide shall nearly ecpial the quantity of alkaloid in solution. The crystals slowly formed in dilute solutions are leaf- form. In acidulous mixtures of sufiicient concentration bihydriodide of quinidine is formed, in golden crystals, soluble in 90 parts of water at 15° C. (De Veij). — With the alkalies and alkali carbo- nates quinidine gives nearly the same reactions as quinine, the T)reeipitate being very much less soluble in excess of ammonia. In presence of quinine the quinidine precipitate requires a good excess of ammonia to dissolve it, and the precipitate is apt to re- appear, crystalline on standing. — With the general reagents for alkaloids quinidine reacts nearly the same as quinine, so far as the reactions have been examined. — -The dextrorotatory power of quinidine is given on p. 123. e. — Separations of quinidine are obtained chiefly (1) by its crystallization as hydriodide (c/, /"), and (2), except from cincho- nine, by solution of the sulphate in chloroform (c). See Separation of Cinchona Alkaloids, p. 112, for an index of methods of separa- tion. Also compare the special separations of Quinine (/"), p. 141. CINCHONIDINE. 1 5 7 ;f.—Qunnt'd(ti'tve. — In estimating quinidino as liydriodide, crys- tallization is secured, as indicated under (/, ,i;-ivin^- twenty-four hours for the crystals to foi'ni. The . The C)'ijffiilliii.e farinii (ukI hcid-ri'iiii'iniiK of cinchonidine mid il.s milis are u'iven under n. and ihi'xv sol uhil It! I'n under f (p. 15S). Cinclifjiiidine is characterized by fln'tnhuit rcoction.t stated under ' Also of Wi.vcKLER, 1S44 Soc- foot-nole uiulcr Quinidine (p. 154). This alkaloid, isomeric with cinihoiiiiie or n mixture containing it, was named cin- ch/ividiiie by Pastkcr in lS5:j, and by Wittstkin in IHSlI. At present all au- thorities agree in this name. ■' Skraup, 1878. Pastkub, CjoHuNjO, 1853. St'c foot-note under Cincho- nine. 158 CINCHONA ALKALOIDS. d (p. 159), tfbe tartrate precipitate with concurring qualitative re- actions being the chief dependence for identification. The alka- loid is estimated by weight of the tarti-ate or of the free alkaloid {/)■ The tests for inqjnrities and the amount of water of crys- tallization of the sulj)hate are discussed under g, p. 160. a. — i'rystdUisafion and heat reactions. — Cinchonidine crystal- lizes, anhydrous, in distinct, lustrous forms ; from alcohol in short prisms ; from dilute alcohol in fine, thin plates. It melts at 2(H)°-201° V. (Hesse, Glaus, 1881).— Oiiwhonidine sidphate cvys,- tallizes in white, silky, lustrous needles or in thin, quadratic prisms. "In colorless silky crystals, usually acicular" (Br. Ph., 1885). " Ordinarily from aqueous solution little concentrated, in bril- liant needles, with OH^O- From concentrated [hot] aqueous so- lution, in [hard] prisms, \vith-3IIo(). And from alcohol in Hue prisms, with 2B..,0. Tlio salt with till^O is officinal" (Ph. Fran., 18S4). The crystals Cdntaiuing 61i.,() effloresce to some extent in the air, losing either one or four of tlie GHgO, as determined \>y the mode of production oi the crystals (Ladenburg's " Ilandwor- terbuch"). In moist air the anhydrous salt gains 2H2O. All water of crystallization is expelled on the water-bath, Cinchoui- dine sulphate with quinine sulphate crystallizes with GHgO (Kop- PESCHAAE, 1885). — Ciiichoiiidine hydrochloride^ with 1 molecule of II^O, forms characteristic crystals, double pyramids, octahe- drons (Hesse). From supersaturated solution silky, prismatic needles are sometimes obtained, with 31I.j(J. A bihydrochloride is also obtained, forming large, lustrous, monoclinic crystals with 1 molecule of water. — Cinchonidine hijdrohromide crystallizes, with H3O, in long, colorless needles (Ph. Fran.) The dihydro- bromide, with 2IIoO, crystallizes in very slightly yellowish pro- longed prisms (Ph. Fran.) — Cinchonidine tartrate, normal, with 2H2O. is a M'hite crystalline precipitate, becoming anhydrous at 100° C. — Cinchonidine oxidate, normal, crj'stallizes, with 2 or 6 IToO, in prisms or a crystalline powder. i. — Cinchonidine has a very bitter taste, and is administered in doses not far from those of (quinine. In excess it is liable to prove poisonous, with action resembling that of picrotoxine (See and BocHEFONTAiNE, 188,5). Death has resiilted from taking 160 grains (Williajvis, 1884). c. — Solubilities. — Cinchonidine is soluble in 1680 parts of water at 10° C., in 20 parts of 80^ alcohol, in 76 parts of ether of sp, gr. 0.729, and easily soluble in chloroform (Hesse, 1865). In 16.3 parts of alcohol of 97^ at 13° C, and in 188 parts ether CINCHONIDINE. 159 of sp. gr. 72 at 15° C. (Hesse, ISSO). Readily soluble inamyl alcohol. Slightly soluble in auuiiouia. In presence uf quinine its solubility in ether is increased. The normal salts of cinchoni- dine, with ordinary acids, are neutral. L'hiclionldlne >ljri)ini(k\ CigI-l2oX.30HBr.H/J = 393 (Br=80), is soluble in 40 parts of cold water, and freely soluble in hot water (Ph. Fran.) — ('inclio- nidine tartrate, (CigHoo]SroO)2C4ll60e. ^ILO, is soluble in 1205 parts of water at 10° C, less soluble in solution of rochelle salt. — The normal uxalide. (CjgllogNgOloIIaCJ )4. 6II.3( ), is soluble in 252 parts of water at 12° C. for 1 part of tlie anhydrous salt. d. — Cinchonidine does not form fluorescent solutions nor give the thalleioquin reaction. — Potassium sodium tartrate and other normal tartrates precipitate cinchonidine, as normal tar- trate (see above, c), crystallizing from hot solution in flne nee- dles. An excess of the reagent renders the test the more delicate. A separation from cinchonine, and to some extent from (piini- dine, hardly at all from quinine. — Cinchonidine is preci])itated from solutions of its salts by the alkalies and alkali carl)oiuites, the precipitate appearing at flrst amorphous, slowly becoming crystalline, and being somewhat soluble in excess of aniuiouia (see Quinine, g, " Kerner's Test "). The general reagents for alkaloids give customary reactions with cinchonidine. — In the test for io(losulr)hiite (sec Quinine, r/, IIcni])athite, p. 131) green crystals of golden lustre are ol)tained. — Ucs])ccting the mici-oclu>- mical test with sulphocyanate, set^ under Cincliona Alkaloids, p. 101; the levorotatory power, ]). 122. e. — tiiqia rations of cinchonidine are indexed under Cinchona i6o CINCHONA ALKALOIDS. Alkaloids, Separation of, p. 112. Compare also with special methods for the separation of Quinine, p. 139. f. — Cinehonidine can he estiindted, gravimetrically, as anhy- drous alkaloid hy drying the precipitate obtained with sodium hydrate on the water-bath [a). More often it is estimated (ac- cording to directions given under Cinchona Alkaloids, Separa- tion) by weight of the anhydrous tartrate (C-^gllooNoOjyC^HgOg = ToS (Tit. 07^ cinehonidine). The precdpitate is dried on the water-bath. — As to optical estimation, see p. 121 imder Cin- chona Alkaloids. — For estimation in mixture with quinine, both as sulijliates, by action of ammonia, see under Quinine, g, " Iverner's Test." g. — Tcstts for imj>urit'tes. — "If 0.5 gram of the salt [sul- phate] be digested with 20 c.c. of cold distilled water, 0.5 gram of tartrate of jjotassium and sodium added, the mixture mace- rated, with frequent agitation, for one hour at 15° C. (59° F.), then filtered and a drop) of water of ammonia added to the fil- trate, not more than a slight turbidity should appear (absence of more than 0.5 per cent, of sulphate of cinchonine, or of more than 1.5 per cent, of sulphate of quinidine)" (U. 8. Ph., 1880).' The test originated with Hesse (lS75j, who directed to digest 0.5 gram of the salt with 2() c.c. water at about GO°C., add 1.5 gi-ams of the tartrate, and after an hour filter find test with am- monia. The Ph. Fran. (ISsl) directs digestion witli boiling water. It) parts, and an excess of the tartrate, then setting aside 21 hours before testing. The three parts of tartrate directed by Hesse give a little closer results than are obtained with addition of one part (o, p. 159). The test does not reveal quinine, tartrate of which takes 910 parts water at 1(1° C. to dissolve it, but shows either cinchonine or quinidine. To test for presence of quini- dine, add to the filtrate fi'oni tartrate precipitation potassium iodide equal to quantity of cinehonidine salt taken, and stir from time to time, when quinidine will be revealed by precipitation, and the second filtrate can be tested, •with a drop of ammonia- water, for cinchonine. Either cjuinine or quinidine will be re- vealed by fiuorescence (Quinine, d). — The sulphate " should not be colored by addition of sulphuric acid (absence of foreign or- ganic matters) " (U. S. Ph., 1880) ; should not suffer " more than a faint yellow coloration" (Br. Pli., 18S5). As to amount of ci-y-stulHaaiiim-water in cinehonidine suJ- p/idte, see a. The loss \>\ (h-ying at 100° C. is limited by the '■ Teeter, Univ. Mich., 1880: New Rem., 9, 358. CINCHONINE. i6i U". S. Pli. and Br. Ph. to the amount of 3II.,0, or Y.S per cent.; by the Ph. Fran, to the proportion of 011._.(J, l."..(j() per cent. Five ordinary coniniercial samples, dried at lnu° ('. and cooled in a desiccator, gave a loss of from (1.36 per cent, to 7.U-1: per cent.' Cixcuo.vixE. Ci,,II.,.,\.,() = 21)4.' Crystallizes anhydrous. — See Cinchona Alkaloids, p. 1>7, for yield in cinchona harks, and p. 9S for ehemieal constitution. Methods of Separation from the Bark, in the total alkaloids, are given pp. 102 to 111. From tlie other cinchona alkaloids the methods of separation are indexed at p. 113, the means of distinction are indexed at p. lOO. Methods of microscopic in- qiiiry, p. 101. Botatory Power, p. 123. Crystalhzation and Heat-Keaetions for the alkaloid and its salts, below. Solubili- ties of the alkaloid and its salts, p. 1G2. Physiological effects, p. 162. Cinchonine is 'identified by the agreement of a number of al- kaloidal reactions and soIid)ilities, and, after separation, by nega- tive results excluding other alkaloids {d) ; the reaction with fer- rocyanide, carefully obtained under the niagnitier, is somewhat characteristic, as likewise is the iodine reaction. For separations, references are noted, in addition to those above, at e, p. It'ii. The alkaloid is estunated by its weight in the free state, anhy- drous (/"), and has been estimated by flayer's solution (p. IGi). Tests for inirity are given {g) at p. 164. a. — Ci'ijstaJlizatioii, and. Ileal -Riavtians. — Cinchonine ap- pears in white prisms or needles, anhydrous, in the monoclinic system, obtained by crystallization from alcohol. In watery so- lution of its salts ammonia gives a tlocculent, crystalline precipi- tate ; in solution of its salts in dilute alcohol needles are obtained by action of ammonia. It melts at 26S.sH'. (Skkacp, 1878). Quickly heated, at 2l:S"-252"' C; slowly heated, at 236° C. (Hesse, 1880). Heated, not quite to the melting point, in a stream of hydrogen or ammonia, a sublinjate is obtained, of undecomposed cinchonine, in prismatic needles, with products of partial decom- ' Taking cinctionidine at (',bH52 . ., 6njO=13. 60 per cent, of the sulphate. at Colli, . . ., 6Il,0 = l3.i:i at C.JIjj . . ., 3HjO= 7.80 atCoHi* . . ., 31150= T.O;j 'Skbaup, 1878. Pasteur, 1853, CioH^iNjO. SUraup found it necessary to separate Oinohotine, C,9ll2! the re- agent. — If a wai'ni-saturated alcoholic solution (if cinchonine be neutralized with hydrochloric or very slightly acidified with acetic acid, then to each c.c. about 10 di-ops of a one percent, so- lution of iodine with potassium iodide be added, and water added 1 64 CINCHONA ALKALOIDS. to incipient precipitation, fine, lustrons red-brown to brown-yel- low crystals of superiodide are gradually formed in the cooling of the liquid. The forms are four-sided rhombic plates. Under just these conditions, and in absence of sulphates, quinine gives a precipitate of taiTv consistence (Baefoed, ISSl). Treated as a sulphate, as directetl under Quinine, d, for herapathite, cincho- nine gives nearly black crystals, brown to brown-yellow when in thin layers under the microscope. The general reagents for alkaloids precipitate einchonine, in most cases quite perfectly. Tannic acid gives a precipitate not easily dissolved l)y hydrochloric acid. The alkali hydrates and carbonates give a quite complete precipitate of cinciiouine (see a), not at all soluble in excess of sodium hydrate, and (in absence of other cinchona alkaloids) almost insoluble in excess of ammonia. (See under Quinine, ^, " Kerner's Test "). In dilute solutions, and more favorably with excess of ammonia, the precipitate becomes crystalline on standing a short time, and is seen under the microscope in radiating tufts of needles. e. — Sepii rations of einchonine are indexed under Cinchona Alkaloids, Separation of, p. 113. Compare also special modes of separation of Quinine, p. 139. f. — QiKintitative. — (Jinchonine is estimated, gravimetrically, as free alkaloid, anhydrous. From aqneous solution of its salts it is precipitated by solution of sodium hydrate, washed with water, and dried at 100° C. It may be estimated by alkalimetry, with tenth or hundredth normal sulphuric acid solution. With Mayer's solution the equivalent of 1 c.e. was given by Mayer (1862) at 0.0102 gram, and the composition of the precipitate was indi- cated to be CiglTogNoO HI Hgig by Groves (1859), but further data are needful as to the value of the precipitation, and the action of the reagent is greatly affected by conditions. g. — Tests for lisfinctions and impurities. — " A solution of the alkaloid in dilute sulphuric acid should not exhibit more than a faint blue fluorescence (absence of more than traces of quinine or quinidine). On precipitating the alkaloid from this solution by water of ammonia it is very sparingly dissolved by the latter (difference from and absence of quinine), and requires at least 30O jDarts of ether for solution (difference from quinine, quinidine, and cinchonidine).'' If the sulphate " be macerated for half an hour, with frequent agitation, with 70 times its weight of chloroform at 15° C. (59° F"), it should wholly, or almost wholly, dissolve (any more than traces of sulphate of cinchoni- QUINOLINE. 1 6s dine or sulphate of quinine reniainini,' undissolved). It should not be eolured by contact with sulphuric acid (absence of foreign organic luatters)."" "If 1 gram [of the sulphatej be dried at 100° C. until it ceases to lose weight, the residue, cooled in a desicca- tor, should weigh not less than 0.1)52' gram" (U. S. Ph., 1880). "Twcntv-tive grains of the salt should lose 1.2() grains of mois- ture when dried at 212° F. (100° C), and should then almost wholly dissolve in four ounces by weight of chloroform " (Br. Ph., 18S.-)). QiiNOLiNE. — Chinoline. Leucoline. C9l-l7X = 129. — The structure of naphthalene with N in the place of one ('H (Korner, iSTti). (See under Constitution of Cinchona Alkaloids, p. 97). An artificial volatile alkaloid obtained as follows: (1) By distilling cinchonine or quinine, strychnine or brucine, with fixed alkali. In presence of copper oxide the (juinoline is obtained nearly free from lepidine (Cj^QUgX) and dispoline (CijII^^N), next homologous members of the quinoline series (Cnllan_5N). (2) Tiie later distillate of coal-tar, the " dead-oil," contains qui- noline. For S(jme years this product was held not identical but only isomeric with the quinoline from cinchonine, and it was named /f//(v;/<'//<', CpII^X. \\\ 1883 IIoogkweeff and v. Dorp obtained cinchonine-quinoline free from previous impurities, whereby its identity with the quinoline of coal-tur or bone-uil is believed ti:i be estalilished. The same investigators, howevei', find an isomer of quinoline in bone-oil. (3) From bone-oil. (4) By synthesis in several ways, best from nitrobenzene, with ani- line, according to the equation on p. '.»7. As obtained from these several sources (quinoline is itself one body. But as manufactured, either for coloring matters or for me- dicinal purposes, quinoline is likely to ivtain some degree of impurities derived from its sources. Cincho-quinoline is ac- companied by lepidine. Artificial quinoline is sometimes inter- mixed witli nitrobenzene. ('Ci-fainly for medicinal uses, at pre- sent, quinoline offered for sale should be presented with the name of its source. a. — Quinoline is a colorless, mobile liquid, transparent when pure, very refractive, and turning lirown bv exposure in the air and light. Specific gravity, at 15°(;., 1.084- ; at 20°C., com- pared with water at same temperature, 1.09-1 (Skrait, 1S81). Boiling point, 231.5° C. (Spai/feholtz) to 241.3° (!. (Kretschy, ' If cinchonine be CsHjj . . ., 2Il50=4.!i!) per cent, of the sulpliate. CoHu 2H,O=4.80 1 66 CINCHONA ALKALOIDS. * 1881). It evaporates slowly but completely, on exposure^ so that the oil-spot it forms on paper disappears on standing. Crys- tallizes in a freezing mixture of carbon dioxide and ether. — The hydrochloride crystallizes in small white nodules ; the tar- trate in rhombic needles, forming under the microscope in colum- nar needles of good length ; the salicylate appears in a reddish- gray powder. i. — Quinoline has a pungent, aromatic taste, slightly resem- bling peppermint-oil in its after-taste, without bitterness. It has a slight aromatic odor like bitter-almond oil. It is administered in doses as high as 1 gram (15 grains) or 2 grams (30 grains) in twenty-four hours (Donath, 1881) In overdoses, to animals, it promptly causes death by asphyxia.' It is strongly antiseptic and antizymotic. It coagulates albumen and myosin (Berbns). It prevents the lactic, not the alcoholic, fermentation (Donath). It is not found in the urine after administration. c. — Soluble in water, sparingly when cold, freely when hot. Soluble in all proportions in afcohol, ether, and carbon disul- phide, and soluble in chloroform, benzene, amyl alcohol, carbon disulphide, and in fixed and volatile oils. The salts of quinoline are soluble in water. The tartrate, {C\IlQN)3{CJ:jQ0g)^ (Feiese, Beenthsen, 1881), is soluble in 80 parts of water at 16° C; in 150 parts of 90^ alcohol at 16° C. ; in 350 parts of ether. It melts at about 125° C. The hydrochloride, CgllyN.HCl (Oechsnee, 1883), is soluble in water, a-lcohol, chloroform, ether, and benzene, in the last two solvents sparingly in the cold. Melts at 94° C, and vola- tilizes. c^.^Quinoline is indicated by its odor, obtained from its salts on addition of a fixed alkali. Alkali hydrates precipitate it, in solutions not dilute ; the precipitate being soluble in ex- cess of ammonia, and easily taken into solution by ether, chlo- roform, and other solvents of the base. Solutions of quinoline salts are precipitated by the general reagents for alkaloids. According to Donath, the limits of precipitation, in certain favo- rable proportions of reagents, were as follows : For iodine in iodide of potassium, 1 to 25000 parts ; phosphomolybdate, 1 to 25000 parts ; mercuric chloride, 1 to .5000 parts ; potassium mercuric iodide, 1 to 3500 parts. The precipitate with phosphomolybdate, yellow- white, dissolves colorless in ammonia ; with mercuric chloride, white. The precipitate by potassium mercuric iodide, 'Berens, 1885: Ther. Gazttte, 9, 433. KAIRINES. 167 on adding hydrochloric acid, crystallizes in amber-colored needles. No color is caused by sulpliuric or nitric acid (Dunath). Jjy long heating with excess of sulphuric acid quinoline sulphonic acid is formed. Tests for I nipur'tties. — In artificial quinoline by Skraup's process, nitrobenzene has been found as an impurity ((J. Ekin, ISSli). The salts should be completely soluble in water, the free base in water with sufficient acid. There should be no bitter taste (impurity from cinchonine). Alkali hydrates sliould not cause a colored precipitate. Cinchonine-quinoline, as prepared for use, and unless repeatedly distilled and recrystallized, con- tains lepidine (Hoogeweeff and v. D ) ; and therefore when treated with aniyl iodide, and then with caustic alkali, gives a blue color, formation of a cyanine (Willia3is), CgPI^NCgHj^j^ . Cj^QlIgNC ^-IIj^j^I. — Aqueous solution of pure quinoline salt [not alkalinej does not sensibly change the color of permanganate so- lution in the first eight or ten minutes (ITagee). Kaieines. — Methyl or ethyl substitutions in oxy-quinoline- tetrahydride, C9Hj^o(OH)jSr. The methyl compound is CgHg (CH3)(On)X=CioiIi3]SrO ; the ethyl compound, C9H9(C,H5) (OIi)ISr=:()j^^H^5NO. The name kairine is used for the hydro- chloride. Oxy/tydro-)nethylquiiioUne is termed Kairine JM, and oxyhydro-ethylquiiwllne Kairine E or Kntroline. Derivatives of quin(dine (E. Flschee, 1883) of medicinal interest. The free bases are not stable in the air. a, c. — Till' methyl hase crystallizes in rhombic forms ; is spar- ingly soluljlein water, soluble in alcohol, ether, and benzene, and acts as a strong base in forming ^alts. It boils at 114" C. The hyilroi:hl(iri(h', ( '-^oII;^3XO . ITC1-|-H.j0, forms lustrous, monocli- nic crystals, generally found in a slightly colored crystalline pow- der, easily soluble in water. At lli.i'' C. it loses its water of crys- tallization and turns violet. The sulphate, (CjoH[j.j\0)oHoS()^, forins lustrous prisms. The ethyl base crystallizes in scales or plates, melting at 76° C, slightly soluble in water, freely soluble in alcolujl, ether, and ben- zene ; hardly soluble in petroleum benzin. The hyJroehiloride, C^j^IIigNO. IICI, forms white prisms, generally appearing in grayish-yellow crystalline powder, freely soluble in water, spar- ingly soluble in hydrochloric acid. J. — The kairines have a bitter and saline, disagreeable taste and a penetrating odor. (Ordinary doses are one-half to one gram i68 CINCHONA ALKALOIDS. (7^ to 15 grains), and doses of 25 to 50 grains cause disturbance." It is in part excreted unclianged in the urine (Merino, 1SM4), The ethyl compound differs from tlae methyl compound only in a somewhat longer duration of effect (Filehne). d. — Kairines are indicated by the penetrating, characteristic odor of the free base, obtained in full from the salts on adding a fixed alkali, and by the bitter taste. In aqueous or alcoholic so- lution, treated with oxidizing agents, as dichromate and an acid, they give rosaniline colors, violet-blue to violet-red, in some reactions greenish tints being obtained. Ferric chloride gives a brown color in solutions, with gradual precipitation. Sodium nitrite in sulphuric acid solution gives orange to red colors. Po- tassium ferrocyanide gives an abundant precipitate ; phospho- tungstic acid a pale yellow precipitate. When the base is Libe- rated, as in alkaline solutions, the kairines rapidly oxidize in the air, with deposition of brown, humus- like bodies. Thalline. Cj^oHj^glSTO. Tetrahydroparaquinanisoil. — A de- rivative of paraquiuauisoil." One of the methyl kairines, isomeric with "kairine M." Thalline appears in pale yellow crystals, melting at about 42° C, boiling at 282° C. without decomposition. Its salts are given in doses of 0.25 to 0.75 gram. It is sparingly soluble in cold, more freely in hot water, and soluble in alcohol, ether, and petroleum ether. It makes stable salts ; but in all forms it is easy to suffer change, and the light affects it injuriously. The sulphate and tartrate are obtained in nearly white crystals or crys- talline powder, melting at 100° 0., with browning. The sulphate is freely soluble in water, nearly insoluble in ether, but is some- what soluble in chloroform. OsSdizing agents produce an intense green color with thalline, hence its name. Ferric chloride is a favorable oxidizing agent for the purpose, giving a deep emerald- green color, not changed by acidulation with sulphuric acid, but changed by reducing agents. — In physiological effect thalline resembles the kairines.' ANTiPTEmE. Cii^H^olSroO. — A proposed commercial name for Dimethyl-oxy-quinizine," C9TTg(]Sr.CH3)(CH3)(0)]S", the hypo- thetical base quinizine having the general formula C9lIg(NII)]S' 'On use of kairine as an antipyretic, Filehne, 1883-1883. American uses summarized in Ther Gazette, 9, 122 (Feb.. 1885). ^VuLPius, 1883: ArcUv d. Phar., [.3], 22, 840; Jour. Chem. Soc, 1885, Abs.,398, 1022. 3 Beyer, 1886: Am. Jour. Phar., 58, 196. Jaksuh, 1884 ANTIPYRINE. 169 (L. Knoee, 1884"). Of interest for medicinal uses as an anti- pyretic. ^•—^ntipyrine crystallizes in needles, melting at 113° C In commerce it appeai-s as a white, crystalline powder, sometimes slightly colored. 5.— Of a very mild bitter taste, not disagreeable, and a barely perceptible odor. Dose, 1 to 2 grams (15 to 30 grains)." Double that of quinine (Butlee, 1885). 4U to 50 grains have caused se nous effects. It appears in the urine in about two hours after Its administration, and can be detected by applying the ferric chloride test to the entire urine (Caeuso, 1885). c— Dimethyloxyquinizine is very freely soluble in water, al- cohol, or chloroform ; in about 50 parts of ether. The aqueous solution is neutral to test-papers. Antipyrine is a base of some strength, uniting with acids to form salts, from which it is set free by the alkali hydrates. <^- — Ferric chloride solution gives a decided red coloration, intense in solutions of 1 to 1000 parts ; the color being changed to yellow by strong acidulation with sulphuric acid.' Nitrous acid, as obtained by adding a httle potassium nitrite and acidu- lating with dilute sulphuric acid, gives a bluish-green color in dilute, a green crystalline precipitate in concentrated, solutioii.s — characteristic of all the quinizines (Knoee). Two drops of fuming nitric acid, added to 2 c.c. of a 1 per cent, solution of antipyrine, cause a green color, and, after heating to boiling, another drop of the reagent gives a red color (Germ. Ph. Commission). Tannic acid gives a white precipitate in a 1 per cent, solution. Testis for rnqniritieK — The solution iu two parts of water should be neutral, and colorless or faintly yellowish, free from sharp taste, and not changed by solution of hydrosulphuric acid (Germ. Ph. Commission). CINCHONICINE.— See Cinchona Alkaloids, pp. 91, 94. CINCHONIDINE.— See Cinchona Alkaloids, pp. 157-161. ' The cjuinizines are derived from quinoline by the introduction of (NH), with additional 2H, into the quinoline molecule. The (NH) is attiiched to the N in the ring, this N being united to carbon by only two bonds, instead of three as in quinoline. Knore: Ber. deut. chem. 6V'.s'., 17, 54(i, 2033; Joi/r Ghent. Soc, 1884, Abs., 302, 1153, 1377: Am. Druggist. 13, 3:!li, 198, 228(1884). 'Respecting physiological and therapeutic effects, Tker. (lazeAie, 1885, 9, 344, 176, 517. Also Pilehne, 1885: Zeitsch. Klin. Med., 7; Am. Druggist, 13, 198. 'Pharmacopoeia Commission of Germ. Apoth. Association. I70 COCA ALKALOIDS. CINCHONINE. — See Cinchona Alkaloids, pp. 161-165. CINCHOTANNIN.— See Tannins. CINCHOTINE.— See p. 93. CINNAMIC ACID.— See p. 69. COCA K'LKh'LOlDS.—Alkaloids of Erythroxylon Coca leaf. Cocaine, Cj^^Hgj^NO^. The crystallizable natural alkaloid of fresh coca. Ecgonine, CgHj^gNOg, crystallizable. A product of cocaine by saponification, and liable, also, to be present in the leaf. Jiemoyl-Eogonine, Q-^^lj^^^O^, crystallizable. A by-product of manufacture of cocaine from coca. (Present in the leaf ? ) Anhydride of ecgonine, CgH-^glSTOo, crystallizable. Producible from ecgonine by moderately strong sulphuric acid with heat. Hygrine, a liquid volatile alkaloid (Lossen, 1865) little known, reported to form crystallizable salts. The existence of this alkaloid is not established. Amorphous alkaloids of coca. (" Cocainoidine, Cocaicine".) Said to be obtained in preparation of cocaine. Probably present in the leaf in some conditions of this article. Not studied. Chemical constitution. — Cocaine, as an easily saponifiable body, prone to split, by hydration, into ecgonine, benzoic acid, and methyl alcohol, clearly has the immediate structure of me- thyl benzoyl ecgonine: CgH^CCHg) (C7H50)N03=Ci^H3;lN04. The saponiiication of cocaine is accomplished by an acid which takes ecgonine into combination, or by an alkali which takes both benzoic acid and ecgonine into union, or even, it is pro- bable, by digestion with water, whereby benzoyl and methyl slowly become hydroxides. But whenever the necessary condi- tions are fulfilled with any saponifying agent, the change is shown by the equation : CgHiglCHg) (C7H50)N03+2I-I,0 =G^li.,~^0^+C^ll-fi . OH+CH3 . OH. Ecgonine, by loss of COg, gives the constituents of a tropine. This change, effected by distilling tlie barium compound of ecgonine, shows a not distant chemical relationship between COCA ALKALOIDS. 171 cocaine and the atropine group of alkaloids. And, like atro- pine, cocaine in decompositions is liable to foriri quite simple pyridine compounds, showing a direct relation to the pyridine series. The S(tj>o/i/Jivafi(>/i.'< of certain other well-known alkaloids, by digestion witli alkali, or with acid, or with water, as stated in each instance, may be compared by the following equations. When the change is effected by acids the produced alkaloid is left in a salt ; but when by an alkali, the produced acid is left in a salt. Ecgonine unites both with acid and with alkali. C1-H23NO3 (atropine) + H20=C8Hi5lSrO (tropine) + C9H10O3 (tropic acid). C33H43NO1.3 (aconitine)-|-H30^CQgH3glSrO;^j^ (aconine)-|-C7Hg02 (benzoic acid). C1-H01XO4 (cocaine) + 2 H.,0 = C9Hi,-X03 (ecgonine) + C^HgOa +01140 (meth. ale.) Co^H.jgXO^ (narcotine) -f- H3t)^C\oHi5N03 (hydrocotarnine) 4-('io^^io^^5 (nieconine). C3oH^9XU9 (cevadine) + 1130=0271143X08 (cevin) + CgHgOa ( uiethylcrotonic acid). C37H53X(_)^ (veratrine) + H„0 = 0o8ll4,,X08 (vcrhi) + O9H-L0O4 (veratric acid). Ci^HigXOg (piperine) +IIoO=C5lInX (piperidine) +OjloHio04 (piperic acid). Except narcotine (and possibly piperine) the saponifiable alka- loids here given are the representative medicinal constituents of the plants wherein they are found : cevadine being the most active constituent of veratrum veride, as veratrine is of cevadilla. The acids formed in the saponifications are aromatic compounds easily reduced to benzoic acid, with the exception of methylcro- tonic acid. Yield of al kill uids from coca leuf. — By the process given following, Dr. Squibb obtains from well preserved lots of the dried leaves, shipped in bales, from 0.5 to OS per cent, of alkaloid. Dr. Lyons obtained from the dried leaves, shipped in bales, 0.65 to 6.7:"), and even O.SO, per cent, of alkaloid. The alkaloidal product of these assays consists, when good leaves are taken, in the greater part of crystallizable alkaloiil. though in some part of amorphous coca alkaloids. The crystallizable alka- loid is probably nearly all cocaine; at least both ecgonine and benzoyl-ecgoninc must be pretty surely left behind in each meth- od of assay, hy the fn^e solubility in water and the very slight solubility in ether of both of these alkaloids. 172 COCA ALKALOIDS. It is noteworthy that all the coca alkaloids, natural or pro- duced, so far as reported, are readily soluble in water as free al- kaloids, save only cocaine itself. Also that ecgonine and ben- zoyl-ecgonine are nearly insoluble in ether, which dissolves cocaine abundantly. The solubilities are further shown here: THE FREE ALKALOID. THE HYDROCHLORIDE. Water. Ether. Water. Ether. Crystallizable : Cocaine Very slight. Soluble. Soluble. Not freely. Soluble. Soluble. Near insol. Near insol. Soluble. Soluble. Soluble. Soluble. Soluble. Soluble. Soluble. Insoluble Benzoyl-ecgonine .... Amorphous : "Amorph. alkaloids." Insoluble. Amoephous Cocaine. Cocainoidine. Cocaicine. — The qua- litative reactions and properties of the amorphous alkaloid ob- tained with cocaine in its preparation are designated by A. B. Lyons ' as follows : The compounds are very difficult to crystal- lize. The precipitate produced in the hydrochlorate by alkalies did not crystallize at all (conijtare below under Cocaine, d)^ neither that by picric acid. In very dilute solutions (1 to 5000) gold chloride produced after some time minute prismatic crys- tals, wholly unlike in general appearance the fern-like forms from the crystallizable salt. Platinum chloride produced a few rosette- like aggregations. — On evajDoration the amorphous alkaloid (pro- bably "not free from non-alkaloidal matter) invariably turned dark, and if the salt was evaporated quite to dryness it was found to be imperfectly soluble in water. Ecgonine. C9HigN03=185 (Lossen, 1865). Crystallizes with iHoO. — A pyridine derivative nearly related to the tro- pines. The alkaloidal body obtained by saponification of Cocaine. It crystallizes from absolute alcohol in monoclinic prisms. Melts at ]98° C, with browning, and decomposes at higher tempe- ratures. Has a slight bitter-sweet taste. It is freely soluble in water, soluble in alcohol, sparingly soluble in absolute alcohol, and insoluble in ether. In reaction it is neutral. It forms slightly crystallizable salts with hydrochloric and other acids, ' 1885: Am. Jour. Phar., $7, 475. ECGONINE.—H YGRINE. 1 73 gummy compounds with alkalies, and a crjstallizable salt with barium. The liydrochlorido of ec'i^(jnine appears in a yellowish, crystalline mass, freely soluble in water and ((Jalmels and Gos- sin) in alcohol. Slijj^htly soluble in alcohol (Lossun). Ecgoniue platinochloride, (('gIii-N().3.IIC'l)„Pt('l4 , is soluble in water; less soluble in alcoln)!. The aurochloride is sobihle in water and in alcohol. IJarium salt of eci^onine (Calmels and Gossin, 1s,^5) forms slender, prismatic crystals, fi-eely soluble in water and in alcoluil, slii^ditly soluble in ether. — When the barium salt of ecij;onine, as obtained, with barium Uenzoate, by saponifying cocaine with l)aryta, is distilled, an isotropine (CgHj-N()j is obtained (Calmels and G.) It will be obscr\'ed that ecgonine, by loss of G<_)j, presents the elements of a tropins. Benzovl-Ecgonine. CjgHj^9NG4= i!8'.t. Crystallizes with 4H.,0. Union of ecgonine witli benzoic acid, the elements of 11./) bein- eliminated: CyH^^XOg.C-II-O. (W. ^[erck, 1885.' Z. II. Skual'p, 18^,5.') — Found as a by-[)n(duct of cocaine man- ufacture from coca leaves. Crystallizes m transparent flat prisms. When quickly lieatcd melts [hydratcd ?] at 90° to lt::i° C, solidities ai;aiii and then melts [aidiydrous ^J at about 102° C. (Skraup). Melts, mth l)ro\vning, at lss.5° to 1S!»° C. (^lerck). Soluble freely in water, sparingly iii alcohol, nearly insoluble in ether. It forms salts: tlie sulphate and acetate crystallize in prisms. The aurochloride, Cj^qIIj.i.XO^. IK '1 . AuClg, forms yel- low scales, .sparingly s(.>lublc in water, soluble in alcohol. — On heating benzoyl-ecgoniiie with methyl iodide and an equal volume of methyl alcoliol, the syntliesis of cocaine is obtained: c,siii9X04+cii.3i = Ci,ii„iX(\. HI. Ax ANHYDRIDE OF Eci;o.\ixE. Cgllj.jXOo- (CAL^[KLS and Gos- si.v, iSS.'j.) — When ecgonine is hcatecl with moderately strong sulphuric acid, an alkaloid is (jbtained which forms readily crys- tallizable salts both with acids and with alkalies, less soluble than corrcspiinding ecgonine salts — the barium salt having the compo- sition BaO.(C,,Hj.,X( ).,).,, and its hydrochloride forming stellate groups of prismatic needles. The ])latinochloridc forms feathery groups of crystals, very soluble in water and in alcohol. IIyukine. a volatile alkaloid found with cocaine in coca leaves (Lossk.v, 18<15'). A thick, oily liquid of a jiale yellowish ^ Bcr. d. chriii. C/es., i8, l.'i04: Jour. ('hem. Soc. Abs., 907. '' Jfona/ftr/i. Cliem., 6, 550; .fnnr. Chem. Soc. Abs,, 1249. Also see Paul. 1885: Phar. Jour. Tmit.s., [3], l6, 325. 'WoHiiER and Lossen: Ann. Chem. Phar., i2i. 374; 133, ;J52. LossEN: "Dissertation." 174 COCAINE. color. Distils slowly with water; distils alone between 140° C. and 230° C. It has an odor resembling trimetlijdamine, and a burning taste. Had no poisonous efEect on rabbits. It is solu- ble in water (not in all proportions) ; freely soluble in alcohol and in ether. It unites with acids, forming salts. The hydrochloride forms deliquescent crystals. It is precipitated by iodine in po- tassium iodide solution, mercuric chloride, silver nitrate, and stannous chloride. COCAINE. Ci7H2iNO4=303 (Lossen, 1865). Chief alka- loid of the Erythroxylon coca leaf (Niemann, 1860). — For the yield from the leaf, and for chemical constitution and relations of the alkaloid, see above under Coca Alkaloids. Cocaine is identified by its eifect on the tongue or eye (J), and the agreement of its precipitations {d). It is distinguished from ecgonine or benzoyl-ecgonine by solubilities of the free al- kaloid in water and in ether {g). Its separations are effected by use of ether, etc., ■A.wAfrom coca leaf by several assay methods (e). Estimation^ gi-avimetrically or volumetrically (/") ; also by ob- taining limits of precipitations (d). Tests for impurities (cj). a. — Cocaine crystallizes in monocHnic prisms, obtained from concentrated alcoholic solution. It appears either in colorless, distinct crystals or in a white, crystalline or granular powder. The alkaloid imperfectly purified from the leaf, or that from in- jured leaves, is more or less dark colored, and contains amorphous coca alkaloid, partly liquid. Cocaine, free alkaloid, is often pre- sented as an amorphous powder, cohering like magnesia (Squibb), and not quite white. — The salts are more crystallizable than the free alkaloid. The hydrochloride crystallizes with a general ap- pearance like that of the free alkaloid ; from concentrated alco- holic solution in short, rough prisms, among which rhombic plates may be found under the microscope ; from dilute alcoholic solu- tion long, brittle needles are obtainable ; from aqueous solution, silky-lustrous needles. The hydrobromide crystallizes in color- less, radiating needles. — The hydrochloride is the chief form of the alkaloid in general use. It is furnished in different styles, including hydrated crystals of good size, minute anhydrous crys- tals, granules of obscurely crystalline powder, and amorphous powder. Cocaine melts at 98° C. (Lossen). More strongly heated it vaporizes with decomposition of the greater portion. The hydro- chloride parts with its water of crystallization (2 aq. ) at or below 100° C. COCAINE. 175 h. — Cocaine has a bitter taste, and is without odor. Its de- composition products in mouldy coCa leaves are said sometimes to present a tobacco-lilve odor. — C'ocaine is distinguislied by an intense local amesthetic and blanching effect upon the mucous membrane, giving on the tongue a characteristic insensibility, a sudden cessation of feeling, lasting but a few minutes (Niemann, 1860). One drop of a four per cent, solution (about 0.04 grain) suffices to blanch the conjunctiva of the eye ; ' and by tlie same application to the tongue (previously rinsed clean) iirst the slight bitterness and then a decided numbness are perceived. These effects are evanescent, unless the application be repeated. The anaesthesia of an eye, for surgical operations, can be accomplished by the application of " 5 drops of a 4 per cent, solution in two installations ten minutes apart" (E. R. Squibb, 1885). — Dilatation of the pupil of the eye is a general effect of cocaine, either ap- plied to the eye or administered to the system. This effect is said not to be invariable ; certainly the midriasis from cocaine is very far from reaching the intensity obtained by the atropine group of alkaloids. JNikolsky obtained with warm-blooded ani- mals a constant widening of the pupil when under the action of cocaine. Dilatation was also observed with frogs. The fatal dose of cocaine was found for dogs, by Danini (1873), 0.15 to 0.30 gram (2J- to 4| grains). In rabbits the hy- podermic administration of 0.1 gram (1^ grain) per kilogram of body- weight caused death in a few hours, sometimes in a few minutes (v. Aneep, ISS(j). The hypodermic introduction of about TfV grain caused dangerous symptoms in a girl of 12 years {Ther. Gazette, Feb., 1886, p. 88). c. — Cocaine is very slightly soluble in water, soluble in alco- hol, ether, chloroform, benzene, petroleum benzin, disulphide of carbon, and in fixed and volatile oils. — The salts of cocaine are soluble in water and in alcohol. The hydrochloride dissolves in less than its own weight of water ; is freely soluble in alcohol, less readily in absolute alcohol and in chloroform, and is practi- cally insoluble in ether, in petroleum benzin, and in fixed and volatile oils. — Cocaine solutions have a strongly alkaline reaction with litmus (not affecting phenol-plithalcin), and form definite salts. The hydrochloride and liydrobromide are neutral in lyar- tion. IlydrocJihiride crystals are permanent in tlie air ; obtained 'This specific use of cocaine was first announced by Div Carl KolliT. of Vienna, at Heidelbcrp, in September, 1KH4 (London Lmirfl, ]HH4, |j. !)!»()). (v. Anrep, 1880; Schroff, 1863.) The extensive use of cocaine as a local anii's- Ihotic rapidly followed the announcement of Dr. Roller. 176 COCAINE. in presence of water they have two molecules (9.6 per cent.) of water of crystallization, but anhydrous crystals can be obtained from alcohol. Hydrobromide cvy&i2i[s also contain two molecules {8.57 per cent.) of water of crystallization. Cocaine citrate is hygroscopic and does not easily crystallize. The oleate of cocaine readily crystallizes, and dissolves in oleic acid or in oils (Lyons). Aqueous solutions of cocaine salts after a few days suffer decom- position of the alkaloid, with vegetable cell growths, unless pre- served by an antiseptic (Squibb, 1885). Neutral solution of the hydrochloride in freshly prepared distilled water, when secluded from the air in glass-stoppered bottles, keeps unchanged several months (Polenski, 1885). d. — The local physiological test upon the tongue, and then upon the eye, for the (evanescent) efEects above detailed, may be resorted to for identification. If the material tested be known only as alkaloidal matter, safety requires that the substance should be obtained in neutral solution of definite strength, the prelimi- nary trials being made with such attenuations as would be harm- less in case of the presence of aconitine or atropine, or other agent of most intense action. In the experiments of De. Squibb (1887) a distinct impression, just short of numbness, was ob- tained by three out of four persons by holding one minute in the mouth Yh> grain (0.00063 gram) of cocaine in solution in one minim of water, tlie mouth having been previously rinsed. When the solution of alkaloid was dried on filter-paper, the limit of re- cognition was found to lie at -^-^ of a grain of the alkaloid, held in the mouth one minute {Epfiemeris, 3, 918). Mayer's solution gives a precipitate with cocaine hydrochlo- ride. According to Lyons (1S,S5)' the precipitate is visibly pro- duced in one drop of a solution of the salt in 12500 parts of water. Precipitates in very dilute solutions are formed by iodine in potassium iodide solution, by phosphomolybdate, and by tannin. Mercuric chloride causes a precipitate in quite concentrated solutions, with a resulting red color like that of atropine (Flijckigeb, 1886). Caustic alkalies, including ammo- nia, added to moderately dilute solutions, cause a precipitation of the free alkaloid. The precipitate has a crystalline structure, either from the first or after standing a short time. Excess of ammonia does not dissolve the precipitate, but any considerable excess of fixed alkali will soon lu'ing about sa])onificati()n of the alkaloid, with partial solution. Tlie alkali carbonates and bi- ' Am. Jniir. P/iar., 57, 473. COCAINE. 177 carlxinates cause precipitation. — Platinum chloride and Gold chloride produce crystalline precipitates, the former reaction re- quiring moderate c(.)nceiitrati<)ii C' c.e. of kerosene. If a layer of emulsion appears it is drawn off separately, and stirred with asbestos, or sand, or dry niter-paper pulp, and the separated kerosene added to tlie larger portion. If the ndxtnre have been shaken instead of stirred, the most of the kerosene will be found in emulsion.^ The kerosene solution of alkaloid (1()(» c.e.) is shaken vigo- rously, in a separatcu-, with two portions of lO c.e. of the acid- water, and one portion of 5 c.e. of the same. N(jw to the %> c.e. of cocaine sulphate solution 10 c.e. of stronger ether ai'c ad to :!:>(;: '• 'I'heerfarbcn," von Dr. U. Nietzki. Pages 337 to 343 : " Ullramarin," von Dr. E. Buchn'kr. IlAciER's "Pharrn. Praxis," Brgiinzungsband, 1883. Pages 951 to 987: "Pigini-nta." Slater's "Colors and Dye-Wares," London, 1879, pp. 317. Serviceable only for commercial definitions. Cbookes, lysS; " Dyeing and Tissue Printing," London. "Bleaching, Dyeing, and Calico Printing." Published by J. and A. Churchill, London, 1883. With an account of Dye-Wares KosTER, 1883: " The Ilygiene of Coal-Tar Colors," Heidelberg. A full re- view in Chem. News, 48, 30. WiTZ, Relation of Colors to Cellulose, 1884: Di}iy. pol. Jour., 250, 371: Jmir. Soc. Chem. Jnd., 3, 306. 1 82 COLORING MATERIALS. For Greens and Yelloivs, from vegetable sources and from coal-tar. — W. Stein, 1870: Pdlyl. Cetdralhl., p. lOflo; Zeitsch. anal. Chem., lo, 115. For all the Colors, mainly those of coal-tar production. — Otto N. Witt, 1886. In the next following pages, with addition of brief definitions of commer- cial names. A quite elaborate scheme, presented by a chemist well known for important contributions on the chemistry of coal-tar dyes. For Colors in tjencral. mostly of vegetable origin. — P. Fol, 1874. Given in the following pages. For the Coal-Ttir Colors, as fixed upon Silk, Wool, and Cotton.— N. Bibanow, 1S7.5: J)[onit. scieiiiif.. [3], 4, 509; Zeitsch. anal. Chem., 14, 106. For Coal-Tar ('uliD-.-t ami VeqcUtble Colors, as fixed upon fabrics. — .J. Joffre, 1883: Jfoiiit. scieidif., [?,]. 12, i).")!); Zeitsch. anal. Chem., 22, 610; Chem. Neirs, 46, 317 (in full): Jour. Sor. Chem. Ltd., i, 447 (in full). For Coal-Tar Bye-Sliiff'.s. — Bockm Ann's " Chemisch-Technische Untersuchungs- Methoden,'' 1884', pp 338-333. For the Principal Colors, taken as free dye-stuffs or in solutions. — Dragen- DOKFF, in "Gerichtl. Chem. Organ. Gifte," 1872. Given in this work in pages following. Presents a method of separation hy the immiscihle sol- vents. For Ciilors in Oeneriil, fixi^il upon dyed and printed fabrics. — Crookes's "Dye- ing and Tissue Printing." 1882," p. 399. For Coal-Tar Colors. — J. Swller, 1880: Chem. News, 42, 191. Witt's Plan of Qualitative Analysis of Commeecial Coloe- iNG Mattees,' chiefly Coal Tar Dyes. A. — Bed Coloring Mutters. I. The color is insolnljle in cold, and with difliculty soluble in hot water, but it is easily dissolved by alcohol. 1. The alcoholic solution is salmon-colored, without fluorescence. The so- lution in strong sulphuric acid is reddish-violet. — Naphthalene-Cctrmine (Kar- min-naphte) 3. The alcoholic solution is reddish blue, and shows an intense orange-red fluorescence. Examined with the spectroscope, it shows a wide absorption- band, which completely extinguishes the yellow and green portions of the spec- trum.' The solution in sul|)huric acid is greenisli-gray. On diluting, the solu- tion first turns red. and then a reddish-violet precifiitate is formed. — Ilagdala- Hed (Naphthalene-lli'd. Ro^enaphthalene). 3. Insoluble in cold water, slightly soluble in hot. Tlie behavior of the al- coholic solution is precisely snnilar to magdala-red, only the absorption-band is more lo the right, so that a portion of the yellow remains visible. The solu- tion in sulpliurio acid is colorless; on diluting, each drop of water as it enters the liquid causes a deep red color. By the further addition of water the whole liquid is colored a deep magenla-red. This reaction is different from that of raagiUrla-red. — Qmnoline-lied. 4. The alcoholic solution fluoresces in a similar manner, but the fluores- cence Is greener. The solution in concentrated sulphuric acid is lemon-colored to orange, and shows no striking change of color on the addition of water. — 'Otto N. Witt, 1886: Tlie Anali/st, 11, 111 (translated by J. T. Leon). Not including anthracene products. 'A good pocket spectroscope, which, with ordinary adjustment, will show Fraunhofer's lines, is sufficient for the examinations in this scheme. WITT'S PLAN OF ANALYSIS. 183 Eosins (tetrahromlhiiiresceins, ('jnllBBi^Oo), soluble in alcohol (to be distin- guished from each other by tlie dijrerence in tint ol dyed specimens). 5. The alcoholic stilution is a dull bluish-red. The solution in strong sul- phuric aciil is frreen, on dilution becoming bluish-red. — lihodidine (Induline of the naphthalene group). II. The coloring matter is more or less soluble in cold water, easily soluble in boiling; water. (f-.— The solution is precipitated by soda. — Basal coloring matters. 1. The solution in water is bluish-red, changing on the addition of hydro- chloric or sulphuric acid to a yellowish- brown. The red color is restored by the addition of sodium acetate. By boiling wool in a dilute ammoniacal solu- tion which has only a slight red color, it is dved a deep n-d. Zinc-dust per- manently decolorizes the aqueous solution. Tiie solid is either in the form of green crystals or has the appeai'anee of a green mel;illic powder, which dis- solves in sulphuric acid to a yellowish-brrnvn solution. — Jlngenla (Fuchsin, Ro- saiuliiie iHunac/d siilt.i. p. I'Jl) '^ The solution is bluish-red. Ammonia gives an orange-colored, fiocculent precipitate, which dissolves in ether to a red solution with a red fluorescence. The solution in sulphuric acid is green; on diluting with water the color changes to blue or violet, and finally lo red. — Tnhnjli'iiii-Rtd (C'lillieN,) (known in commerce as neutral red, generally very impure, and therefore not giving pure colors in the above reactions) h. — The solution is not ]3recipitated by soila. Acid coloring matfern, or basal colors of the Sajfranin class of comiionnds ityjie C'lsHi^N^). 1. On the addition of soda to the aqueous solution a change of color takes place, the solution becoming colored an intense blue. Tlie solution in sulphuric acid is a briiwnish-yellow, becoming somewhat redder on dilution. — Gallein {Fijroiidlldl-jilitliitlnii, C2C1FI10O7). 2. By the adilitioii ol alcohol to the aqueous solution a distinct yellowish fluorescence is produced. The addition of acid produces no precipitate. Zinc- dust decolors the solution, but on contact with air the orij;inal color is innne- diately restoied. The solution in sulphuric acid is yreen, and, on diluting, first becomes blue and finally red. — Snffraiiin and .S'((//V((« ('.?«/ (to be distinguished from each otiier by the difference in tint of dyed specimens). o. Tlie aqueous solution is a jiure red and shows a greenish-yellow fluores- cence, which hecumes more distinct the more it is diluted. The addition of acid gives an orange-yellow precipitate, wliieh is soluble in ether. The elhere.il solution Is a pure yellow, without fluorescence. The solution in sulphuric acid is yellow. — Ehkih (tetraliroinfluorcscein). 4. The aqueous solution is more of a bluish-red and shows no fluorescence. Acids give a straw-colored precipitate, solulile in etiicr lo a liquid of the same color. Concentrated sul [ill uric acid gives a golden-yellow solution. Zinc-dust decolors the ammoniacal solution. If the colorless solution be dropped on blot- ting-paper, it acquires an intense bluish-red color by contact with the air. — Eosin- Scarlet, bromo-nitro-fluoreseeln, C'^JInBrjiND.jK.Oii. 5. The solution is bluish-red, without fluorescence. ,\eids give an orange- yellow precipitate soluble in ether. .Strong sulphuric acid gives an orange- yellow solution. Zinc-dust and ammonia decolor the solnlion, and the color is not restored by contact with air. — I'lilnxin. Bengal-Red. (Kosins, to be distin- 1 84 COLORING MATERIALS. guished from each other by the difEerence in tint. Bengal-red bears more to the blue.) 6. The hot-oonoentrated aqueous solution solidifies, on cooling, to a jelly. The addition of acids causes a brown, flocoulent precipitate. On warming with zinc-dust and ammonia the solution first becomes a bright yellow and then colorless. Concentrated sulphuric acid dissolves it to a grass-green solution. On dilution the liquid first acquires a bluish tint, and then a dirty brown pre- cipitate comes down. — BiehricJt-Scarlet (Double Scarlet. From amido-azo- benzene sulphonic acids with naphthols). 7. Barium chloride gives in an aqueous solution a flocculent red precipi- tate, which, on boiling, suddenly becomes crystalline and acquires a deep violet-black color. The solution is indigo-blue, turning violet and red on the addition of water. — Crncein-Sciirlet, SB {Ber. d. chem. Ges.. 15, 1352) 8. The aqueous solution is colored abriglit blue on the addition of a minute quantity of acid. Cotton-wool l)oiled in an aqueous solution, either with or without the addition of soap, is dyed a fast red. The solution in sulphuric acid is slate-colored, and this tint does not change on diluting. — Gongo-Red. 9. The hot aqueous solution solidifies on cooling, when there appears a sepa- ration of shining, bronze-colored crystals. The solution in strong sulphuric acid is violet, and diluting it with water causes a brown precipitate. — Xylidme- ponceau (Xylidine-red, from alpha-naphthol-sulphonic acid, D. P. 26013). [Riohter's Organic Chemistry, Philadelphia, 1886, p. 453.] 10. The concentrated aqueous solution, mixed with magnesium sulphate, deposits, on cooling, long, shining crystals of the magnesium salt. The solution in sulphuric acid is violet. Wool is dyed by it a brilliant scarlet. — Vrocein- Scarlet, 7B Extra (formed by the action of diazo-naphthionic acid on orocein- beta-naphthol-sulphonic acid). 11. The aqueous solution gives, with chloride of calcium or barium, an amorphous, flocculent precipitate. The solution in concentrated sulphuric acid is rose-red or carmine, and on diluting it a brownish-red precipitate comes down. — Coloring matters from beta-naphthol-disulphoiiic acid, to be distin- guished from each other bv the difference in tint of dyed samples: Ponceau R, 2R, SR. An i sol-Red, corcin. (D. B P. 3229). [Kichter's Organic Chemistry, Smith's edition, p. 460.] 13. Wool is ilyed magenta-red. Chloride of calcium gives, in an aqueous solution, a crystalline precipitate. The solution in concentrated sulphuric acid is bluish-violet, becoming red on diluting. — Acid Azo-Ruhin (D. R. P. 26012). 13. The color of the solution is a deep brownish-red. Wool is dyed the same color. The solution in sulphuric acid is blue; the addition of water gives a yellowish. brown precipitate. The hot-concentrated aqueous solution gives, on the addition of a drop of saturated soda solution, a precipitate of the sodium salt in the form of brown, pearly plates. — Roccellin (Echirotli). [Post's "Chem. Tech. Anal.," p. 983.] 14. Chlorides of calcium and of barium give a flocculent, amorphous pre- cipitate. The solution in concentrateil sulphuric acid is of an indigo-blue. — Bordeaux-Blue (D. R. P. 3339). [Diazonaphthalin-beta-naphtholdisulpho- nate.J 15. The aqiipous solution has a fine bluish-red color, which is completely removed by caiistic soda, and is again restored by acetic acid. — Acid Mngevta [sodium rosaniline sulphonate]. B. — Yellow and Orange Coloring Matters. I. Tlie coloring matter is insoluble in cold water, and either totally or very nearly insoluble in hot water. On the other hand, it is soluble in alcohol. WITT'S PLAN OF ANALYSIS. i8s I. Tlie solution is lemon-eolniod. The color is either unaltered or slightly deepened by the addition of acids or alkalies. — Chinophtalon. [(Jliiraaphiliii.] 3. The color of the solution is golden yellow. It is unaffected by acids. It is turned a deep brownish-red by alkalies and by boracic acitl. — Curcumin dye (Turmeric). 3. The coiorof the solution is golden-yellow. The addition of hydrochloric acid produces a red color. Amyl nitrite added to the hydrochloric acid solution produces no change of color on boiling, nor is nitrogen gas given off. — Dime- thylamido-miibi'iiiiil (fijrnierly used for coloring artificial wax. from ozokerite). 4. Reactions similar lo 3, except that amy) nitrite produces a change of color and a small quantity of nitrogen is given off. — Amido-azobenzol, C,JiBNs.NH.i. II. The coloring matter is soluble in boiling water. Strong sulphuric acid dissolves it without any great change of color. a. — Caustic sotlti produces no precipitate. Acid Coloring Matters. 1. The solution is greenish yellow, having a very bitter taste. Alkalies color it a dark yellow. Unaffected by acids. — Picric Acid ( Trinitrophenic Acid). 3. The solution is golden-yellow. Acids cause a white precipitate. —jWar- tius-Yellow [Naphthalene-Yellow, C,oHs(NOn)j.ONa+H,0]. 3. The solution is golden-yellow; not precipitated by acids. On the addi- tion of chloride of potassium fine, needle-shaped crystals are precipitated. — Add Naphlhol Yellow. 4. The solution is brownish-yellow, and shows a magnificent green fluores- cence, disappearing on the addition of hydrochloric acid, which also gives a precipitate. — Fluorencein (Uranin), Benzyl Fluorescein (Ghrysolin). These two dyes can only be distinguished by a careful examination of the separated color- ing acids. ["Watts's Diet.," viii. 1606. Richter's Chemistry, Organic, Smith's edition, p. 629.] 5. The solution is golden-yellow, and not precipitated by acids. It is not decolored either oy zinc-dust and ammonia or by tin-salt and hydrochloric acid. — Quinoline- Yellow. h. — Caustic Soda gives ti precipitate. Basic Dyes. 1. The precipitate with alkalies is yellow and is soluble in ether to a bright yellow solution, with a beautiful green fluorescence. — Phosphine. [Chrysani- line, CisHiiN(NH2)2, with a little magenta ] (This delicate ether test can also be used to detect phosphine in mixtures, as, for example, with grenadine, ma- roon, etc.) 2. The precipitate with alkalies is milk-white ; soluble in ether to a color- less solution with a greenish-blue fluorescence. — Flavnnilin, CuHuNs. 3. The precipitate with alkalies is milk-white. Ethereal solution colorless, without fluorescence. The yellow solution, when boiled with hydrochloric acid, gradually loses its color, and finally becomes colorless.- — Auramin. III. The coloring matter is soluble in water. The solution in concentrated sulphuric acid has a deep color. Azo-CoLoaiNQ Matters. a. — Soda produces a precipitate. 1 86 COLORING MATERIALS. 1. Tlie color to wool is yellow. The aqueous solution solidifies, on cooling, to a bluish-red jelly. The sulphuric acid solution is brownish-yellow. — Ciiry- «oiiim [diamido-azobenzene. Bockmann's " Chem. Tech. Untersuch.," p. 308]. 3. The color given to wool is orange-brown. The solution does not soli- dify on cooling. The solution in sulphuric acid is brown. — Vesuvin (Bis- 7iiarck-Brown, Manchester-Brown, or Phenylene-Brown). [Triamido-azoben- zene.] h. — Soda does not produce a precipitate. 1. The solution in sulphuric acid is yellow, becoming salmon-colored on diluting. The aqueous solution is yellow. — Trojjcedli-ne- Velio w.' 2. The solution in sulphuric acid is yellow, changing to carmine-red on diluting. The aqueous solution is yellow, and the substance crystallizes out, on cooling, in glittering, golden scales. Dilute acids produce a reddish-violet pre- cipitate. — Meihyl-Oyange. Ethyl-Orange. 3. The solution in sulphuric acid is violet, becoming on diluting leddish- Tiolet, and at the same time forming a steel-gray precipitate. The aqueous so- lution is yellow, crystallizing out on cooling. Calcium and barium chlorides give a completeiv insoluble precipitate — Trupceolin 00. Diphenylamine-Tel- low. [SOjCjH./Nj.NHCIU.] 4. The solution in sulphuric acid is bluish-green, becoming violet on dilut- ing, and forming a steel-blue precipitate. The aqueous solution is yellow; a crystalline precipitate separates from it on cooling. Barium chloride gives a yellow precipitate, which can be crystallized from a large quantity of water in shining plates. — Javiie JV (Yellow N). [Bockmann, p. 310.] 5. The solution iu sulphuric acid is yellowish-green, becoming violet on diluting, and forming a gray precipitate. The aqueous solution is yellow, de- positbig crystals on cooling. Calcium cliloride gives an orange precipitate, which becomes red and ci-ystalliue on boiling. — Luteolin. [CjoHioOs. From protocatechuic acid.] 0. The solution in sulphuric acid is carmine, turning yellow on diluting. The aqueous solution is yellow, often cloudy, and becoming a deep red or violet on the addition of alcuholic soda. — Citronin (Indian-Yellow. Curctimin. Pur- ree). [Euxanthin, CioHieOi,,.] 7. The sulphuric acid solution is a deep orange. On diluting no change of color takes place. The aqueous solution is orange; on adding calcium chloride fine crystals of the calcium salt separate out. — Oninge (I (D. R. P. No. 3329). 8. The sulphuric acid solution is a brown orange. No change of color oc- curs on diluting. The aqueous solution is yellow. A small addit;ion of hydro- chloric acid causes a crystalline precipitate; excess of hydrochloric acid causes a separation of the free acid in gray needles. — Tropwolin (Chrysoin) [Resor- cin-azo-benzene sulphonic acid]. 9. The solution in sulphuric acid is carmine-red, becoming orange on dilut- ing. The aqueous solution is a reddish-orange; chloride of calcium precipitates the fine red calcium salt, which crystallizes from a large proportion of boiling water in needles. — Orange II. (^landarin). [Tropoefilin 000, No. II.] 10. The sulphuric acid solution is violet, becoming orange on diluting. The aqueous solution is orange-red, becoming carmine on the addition of caus- tic soda. — Tropmolin 000 [No. I] (Orange 1). Green Coloring, Matters. 1. Soluble in water to an olive-brown solution. It easily dissolves in alka- lies to a grass-green solution. Concentrated sulphuric acid dissolves it to ' On Tropceolines in general see 0. N. Witt, 1879 : Jour. Chem. Soc, 35, 179. Jl'/T'f'S PLAN OF ANALYSIS. 187 a dirtv brown solution.— (o/-»/r/'«, t'.,„II„(»„. [Post's "Cliom. Tech. Anal.," p. 9U1.] 'i. Easily soliililc in wain-, forming a bright },M-e('n solulion. AlUalii'S give it a rosc-eoloreil or gi-av iirc.(:i|iitatc. Strong acids color it yellow. — Victuria- (Ireen [ilnlacliih'-(l n !■'■< . C,„l 1 k,.\.,(C1I:,), .iui. E. and 0. 'FiscuKu, 1878-711: Ber. d. c/iem. (iis.. ii, ■,'01)5; 12. 7HI'; Jinir. Chciii. S(jr., 36, L'olj. 7H7J. 'A. Keadily sohil)le in waitr, lorniing a fine bjue-grccri solution. Acids color it yellow. Alkalies decolor tiie solution witlmut inoducing any [jrecijii- tate. A s|ieciuien ot stull dyi'd turns violet when healed al>ove 100 ("'. — Iiidi/iK itiid methi/l-i/n en. [licxauiethvl msaniline compound.s. Bockmunn's " L'heni. Tech. Untersuch ." p. :i!)S.] 4. Easily soluble in waier to a cnrrespondingly pale green solution. Acids first dec[ien the color, and then change it to yellow, ^ilkalies coniiilctelN di- colorthe solution. Silk and uool can only be dyed in an acid-bath (dislinction from methyl-green, which will d)e in a neidral bath). Dyed samples can be heated with safety for a short tiiiio to 150 (J. — Jlelretni-dreen. [Alkali-Green.] [Post's " Chem. Tech. Anal.," p. 087. Soilium sul|ihonate of malachite green.] Blue Colorino Matters. 1. Quite insoluble in water, soluble in alcohol to blue solutions of various shades. Hydrochloric acid at first caii~e^ no change, bul on slanding minute, sparkling green cryslal.- are precipitated. Cau-tic so(hi [n-oduces a brownish- red coloration, ('oncenlraled sulphuric acid dissolves it, rorniing a blown so- lution. — liosaniliiie-Blae.' Uip/ieni/lamiia'-Bliie.'' ('I'u be disiinguished from each (jlherby I he difference in tintof dyed silk, e-pccially with anarlificial light ) 2. Insolulile in water. The alcoholic solution is colored red by the addi- tion ot hydrochloric acid. Unaltered by alkaliis. — /oi/r/;y/( iiiii. [Iierivative of Lsatiii, conlaiiiing sulphur.] ■J. Easily soluble in water. Ilydrodiloiic acid gives a greenish precipi- tate. Caustic soda gives a violet -red precipilale. Zinc-dusI reduces it, bLiI the color is restored on contact with the air. It contains zinc. — 31ttliylene-Blue [C16H19N3S. Biickmann's " Untersuchuiigs- Jblhnden." ]i. oOC] 4. Tolcrablv -...hible in water. Acids culor the scjlution yellowish-brown. Alkalies give a red-brown precipitate. — Miiorui-Bliit. 5. Readily soluble in water. The solutmn is almost completely decolored by acids. Wool abstracis the coloring matter from the alkaline solution, and becomes colorecl u dee|i blue after washing with water and treating with dilute acids. — Alkali-Blue R, and GB.^ (Distinguished from each other by the dif- ference in tint ) Ij. Easily soluble in water. Wool can only be dyed in an acid-bath. The aqueous solution is not preci|)itated by alkalies. Zinc-dust decolors permanently. — Wiiter-Bhie (Wasserblau) /,', (\B.' ' " Ani/hie-Bliie." "Insoluble Aniline-Blue." Sprilblan. Triphenyl- rosanillne hydrochloride. Insoluble in water, sparingly suluhle in alcolKd, soluble in acetic acid or in aniline oil. T!ie alkali sul|iliiinatcs of triphenyl- rosaniline constitute "soluble blues," known as "alkali-blue" and "water blue," from the name of the solvent they ncpiire. - Dipheiiylamine-Blue is inferreil to in' atripheiiyl-para-rosaniliiie. It forms a sulphonic acid soluble with alkalies. ""Alkali-Blue" is themojio sulphonic acid of triphenyl-rosaniline. It is not easily soluble in water alone, but on adding alkalies soliitiiiu is readily ob- tained tlirongli formation nf a sulplionale. * " Water- Blue" consists o I' po/?/ suliihonic acids of triphenyl-rosaniline, with (SOsII)^ to (SOallli in the molecule. These suljjhonic acids dissolve in water without the hel[i of an alkali. 1 88 COLORING MATERIALS. 7. Easily soluble in water. Dyes only in an acid-bath. Zinc-dust and am- monia form a vat; that is, the color is restored on contact with air. The solu- tion is permanently decolored by boiling with dilute nitric acid. — Indigo-car- mine. [Alkali salts of indigotin-disulphonic acid, as CjeHsNaOa (S0aK)2 ] 8. Insoluble in water, soluble in alcoliol. Alkalies color the alcoholic solu- tion brownish-red to violet. Strong sulphuric acid dissolves it to a blue solu- tiiin. — Iiididine R, 6B. [Azo-diphenyl Blue.] (The more soluble the dye the redder the color.) 9 Soluble in water. Acids give a blue precipitate. The solution is colored red to violet by alkalies. Zinc-dust and ammonia form a vat. Dilute nitric acid does not decolor the solution, even on heating. — Indulines soluble in water. (Distinguished from each other by difference in tints.) [Bcickmann's " Unter- such.," p. 321.] 10. The commercial product is in the form of a gray paste. Soda solution gives a blue color on exposure to che air. — Leukindophenol. 11. The commercial substance is a gray paste, which dissolves in soda with- out any blue coloration. On adding glucose, and boiling, crystals of indigo- blue separate out. — Ort lio-nil ropheiiylpropinUe Acid. Violet Coloring Matters. 1. With difficulty soluble in water; soluble in alcohol. Sulphuric acid forms a cinnamon-colored solution. — Regina-PurpleiDipkenyl-rosaniUne). 3. Easily soluble in water. Alkalies give a precipitate. Hydrochloric acid colors the solution first green and then yellow. — Methyl - Violet, R, GB Hof- manii's Violet. (Distinguished from each other by the diifereuce in tint.) [Methyl-Violet is pentamethyl-rosaniline hydrochloride. It is the same as " Paris Violet." Hol'mann's Violet is triethyl-rosaniline hydrochloride or hy- driodide. For description see Bockmann's " Untersuch.," p. 296.] 3. Xot readily soluble in water. Alkalies give a violet precipitate. Con- centrated sulphuric acid dissolves it to a gray solution. On dilution the solution becomes successively grayish-gi-een, sky-blue, bluish-violet, reddish-violet. — Mauvein. (Perkin's Violet. Rosulane.) [C-.7H.24N4. By oxidation of aniline oil with dichromate and sulphuric acid. Perkin, 1856.] 4. Soluble in water. Acids give a blue precipitnte; alkalies a reddish- violet precipitate With zinc-dust and an acid, as well as in an ammoniacal solution, it forms an excellent vat. The solution in strong snlphuric acid is emerald-green, becoming sky-blue on diluting. — Lnuf's Violet (Thionin). 5. Only solulile in boiling water. Hydrochloric acid colors the solution carmine-red. Sulphuric acid dissolves it to a blue solution, becoming red on diluting, — Gallo-cyanin. 6 Soluble in water to a reddish-violet solution. The addition of alcohol causes a red fluorescence. Strong sulphuric acid dissolves it to an emerald- gi-een solution; on diluting the color chang(>s to blue or violet. — Amethyst, Fuchsia, Oimflee (Violet Saffranin Dyes). [Saffranines are of the type CieHi4N4 For a brief description of the group see Richter's Chemistry, Organic, Smith's rd., p. 469; Bockmann's "Untersuch.," p. 302.] Chemical Defennijuifion of lied Dye-St^tffs, according to Stein.' With fairies, a small portion, of about one-fourth inch square surface, is treated in a test-tube with a few c.c. of the reagents directed. The resulting color solutions are subjected to the tests, I. The dye-stuff is warmed with ammonium sulphide. It turns more or less blue to greenish.— ^" Aloes Dye," a mixture of Chrysammic and Aloetic acids used upon wool and silk. >W. Stein, 1870: Polyt. Oentralbl.,^. 616; Zeitsch. anal. Chem.,i), 520. STELVS SCHEME. 189 11. The dye-stuff is boiled with aluminium sulphate [filtered, cooled, and filtered again, Goppelsrodeb, 187S], A. The solution turns red with a golden-green reflex. — Madder colors (Note 1, following). B. The solution tiirns red witliout any reflex. On diluting it with an equal volume of sodium sulphite solution, it is (1) Bleached. Aniline reds, Sandal, Jirmil-ieoud, Corallin, and Safflower. Aild alcohol to 80 per rent, and lioil. The solution (a) Colors decidedly (a) bluish-ivd — Aniline-reds (Note 3, p. 191). (b) yellowish-red— »S<(/(rf((/ (Note 3, p. 191). (6) Does not color at all, or noticeably (Safflower, Bi'azil-wood, Oorallin). Warmed with lime solution it assumes (a) no color — Safflower (Carthamus) (Note 4, p. 191), (b) a red color (Brazil-wood and Oorallin). Warmed with dilute sulphuric aeid it becomes (a) orange-red — Brazil-wood (Fernambuc), (b) yellow and discolored — Uoraltin (Note 5, p. 191). (3) Not bleached (liy the sulphite). Arcliil. Lac dye, Kermes, Cochineal. Add alcohol to 80 per cent, and boil. It becomes (a) decidedly red— .lre/((7 (nrxeille)(Niite (i, p. 192), (b) not red, or but slightly (Lac, Kermes, Cochineal). It is warmed by baryta solution. It takes (a) no color — Zy«c Dije, (b) colors (Kermes, Cochineal). It is warmed with lime solution; colors (aa) brown-i'cd — Kermes (Coccus ilieis), (bb) violet — Coe/iineat' (Coccus cacti). JVote 1, upou Stein'.s echeme (almve). The golden-green fluorescence, after hot treatment with ahimiimni sulphate, accord- ing to Stein and others, is a distinction of natural madder-red from other reds, but is wliolly due to the purpurin of the mad- der, and is not obtained with tlie alizarin. Since Stein's report artificial alizarin has gradually supplanted madder, and the latter is not now in extensive use. A brief description of alizarin and purpurin is here appended. Alizarin. ^\i^(\^^i = 240. T)i-livdr(ixy-anthra(]uinone. Ogll^ : (\,(), : C'JI„(Ori)o [Oil : ()II = l': y|. ' -MaiUler-RedP '■'Alisarin-Iied."^ — A product of anthracene. f'j^HjQ, of coal-tar, from which it is now cliietly obtained, liy reactions of oxidation. Before 1^(59 it was wholly obtained from the root of the madder plant, liiihta tinotorum (Krupp, in tiie German). Natural and artificial alizarin are identical when each is perfectly purified. The natural alizarin comes from a glucoside of the plant, rube- rithi'ic acid, ^'o6lh>H^i4- ^^.Y boiling with dilute acids, also by a ferment in the madder root, two molecules of water are taken in, and a molecule of alizarin formed, with two of glucose.— In orange-colored or yellow prisms, or in a brown paste. Melting 'Upon the distinction between cochineal, kermes, and hie, lliree colors alike in most reactions, see Stein's report, Zeitacli. anal. Cliem., 9, .'")22. I go COLORING MATERIALS. point, 2S2° 0. (Schunck). Insoluble in cold, slightly soluble in boiling water ; soluble in alcohol, ether, methyl alcohol, benzene (more readily on warming), or carbon disulphide. Alkalies and alkali carbonates dissolve it in water, the solution being violet by transmitted, purple by reflected light. Concentrated sulphuric acid does not decompose it. From the alkaline solutions acids precipitate it in reddish flakes ; and alum precipitates it with a red color. Alcoholic solution of alizarin, witli acetate of copper or of iron, gives a purple precipitate ; with barium hydrate solu- tion, a blue precipitate. Sublimation is a serviceable means of examining alizarin. Katural alizarin contains Purpurin, and artificial alizarin con- tains Anthraquinone, as impurities. Alizarin itself begins to sublime at 110° C; the two purpurins at 160°-170° C. (Schunck and RoEMEE, 1SS()). The first sublimate from artificial alizarin, at temperatures below 140° C, will contain crystals of anthra- quinone with the long orange crystals of alizarin (Goppelseodee, 1877-78). In natural alizarin — that is, when anthraquinone, hy- droxyanthraquinonu, and the anthrafiavic acids are absent — con- tinued sublimation at 110° C. removes the alizarin, which may thus be estimated by the loss.' The name alizarine, in commerce, has been sometimes applied to an extract of madder flowers ; and to Gerancin, a product of the action of strong sulphuric acid upon madder dye. AlizarinJjliie. Cj^yllj^gXO^. Formed from Alizarin-Orange by heating with sulphuric acid and glycerin. A bluish-violet paste, of about lOfo solid content. Soluble in alkalies with greenish-blue color, an excess of the alkali causing a precipitate. Colored red-brown by suljihuric or hydrochloric acid. Alizarin- Oraiuje. Nilro-Alizurin. CgH^ : CgOo : CgH (N03)(0H)„ [NOy : OH : OH =1 : 2 : 3]. In commerce as a yellow paste. Dissolves in sodium carbonate solution with yel- low-red ; in sodium hydrate solution with a red color; an excess of the caustic alkali precipitating the solution. Purjniriii. C]4TIg05=: 256. Tri-hydroxy- anthraquinone. CgH^ : C0O3 : CgHlOH).,' [OH : OH : 0H = 1 ': 2 : 4]. Can be produced from anthracene. The isomerides hoinirpurin or anthrapurpurin, and 7'7r^?v>^>(/;^>i«-zVt. or "yellow alizarin,'' have a limited empldyinent in dyeing. Purpurin ci'ystallizes in orange-red needles, with one molecule of crystallization-water. 'SrHUNCK and RoEMER, 1880: Ber. d. diem. Qes., 13, 41; Jour. Chem. Soc, 38, 424. The same, 1877: Jmtr. Cliem. Soc, 31, 065. Also, Goppelseo- DER, 1877: Ding, polyi. Journ., 226, 30; Zeitsch. anal. Chem., 17, 510. STEINS SCHEME. 191 It is more soluble than alizarin, either in boiling water, al- cohol, or ether. The solution in alkali is red, in thin layers purple. A dilute alkaline solution soini bleaches in the air and light. With lime or baryta, in hot water, it forms a per- fectly insoluble lake. Boiling alum solution takes up purpurin abundantly, forming a yellow-red solution of sti'ong fluorescence, whereby madder-red is tlistinguished in the scheme of Stein (p. ISS). Note 2, upon the scheme of Stein (p. 189). Anlllne-rcds. Sidin of Jiosa/iilliie, C.QlIj^gNg^ 301 (nioiiol)aKic). The hydro- chloride and acetate, as monacid salts, constitute " Magenta," " Fuchsin," aud "Roseine." The nitrate is prepared as " Aza- leine " and " Rubine." Rosanilines are triamido-toluyl diphenyl methanes, the hvdrated l)ase having the structure (C'gll^. NHo)., (C'oll3(;H3.XH2)C.01I=C\,oIl2iN3(). The base forms m.macid salts of red color, triacid salts of a yellow color, and diacid salts of little stability. — Commercial magenta or fuchsin appears in crystals of green metallic lustre.- It is non-volatile, decom2:)osing at about 220° C. It has a bitter taste. Rosaniline base is very sliglitly soluble in water, but melts in boiling water. The ordi- nary salts of rosaniline, the aniline-reds, are soluble in hot water and in alcohol, tlie solutions having a crimsourred color, and only impurities being left in insoluble residue. Addition of acids changes the color toward yellow, with formation (jf triacid rosaniline salts. Alkalies precipitate free rosaniline and destroy the color of the solution. Warmed with cupric chloride, aniline- reds show a blue color. They dye silk and wool a crimson-red, without a mordant. — JiomouIuk:' j>/cr(i/i' forms line red needles nearly insoluble in water. The ta/nuite is insoluble in water, but soluble in alcohol, methyl alcohol, or acetic acid. Tannic acid precipitates rosaniline from aqueous solutions of its ordinary salts. N'ote 3. SaniJal-reil is turned brown by hot lime solution ; but its red color is intensified and finally clianged toward blue by hot diluted sulphuric, hydrochloric, or acetic acid. Note i. Saffl(jin,'r-rcil (Afi'ican Saffron, False Saffron). The action of the lime solution is to decolor through a cliange to yellow. Ammonium sulphide decolors it, more readily by addition of ammonium hydrate. The )'C(1 color is restored by acetic acid. Note 5. VordUhi-rcd. Peonin. Prepared from Aurin or Rosolic Acid. In violet powder or brown needles, soluble in water as a red solution having an alkaline reaction. With cupric 192 COLORING MATERIALS. chloride it is decolored to gray — a distinction from aniline-red, which is turned blue in this test. Note 6. Ai'chil. Orseille. Persio. The coloring matter derived from lichens of the genera Eoccella and Leconora. Vege- table acids in these lichens are converted into orcin, or orcinol, CeH3(CIl3)(OH)2 [1 : 3 : 5], a di-hydroxy-toluene. With am- nioiiia this gives rise to orcein, or "lichen-red," CyH^JSTOg, the chief constituent of archil dyes. Litmus and Cudbear also con- tain color deri\'atives of orcin, obtained from the lichens. Orcin is manufactured from toluene, as a source of orcein, for dyeing. Orcin is colorless when pure, but becomes reddish-brown by ex- posure to the air. Its crystals, with one molecule of water, melt at 58° C, and becoming anhydrous the mass distils at about 290° C. It is soluble in boiling water, alcohol, ether, or boiling lienzene. It is capable of decomposing alkali carbonates with elfervescence. Hypochlorites give, with even a trace of orcin, a transient, intense purple-red color. Ammonia, with exposure to air, quickly converts orcin into oi'cein, with its deep purple-red color. — Orcein dissolves sparingly in water, to which it gives its red color, dissolves fi-eely in alcohol, and freely in aqueous alka- lies with violet-red tint. Acids precipitate it, in part, from the alkaline solution, and water precipitates it from tlie alcoholic S(3lution. It is bleached by ammonium sulphide ; also by zinc added to an ammoniacal solution previously acidulated. Reactions of Coloring Materials, according to Fol. ' Blues. Solution of citi'ic acid or dilute hydrochloric acid is added. (a) Color changes to red or orange. — Logwood -blue, ih) Color does not change. Solution of calcium chloride is added to a fresh portion of the dye-stuff. {a) Color remains unchanged. — Prussian hlaie. (J)) Color changes. Solution of caustic soda is added to a fresh portion. {a) The substance is decolorized. — Aniline-hlue. (b) It remains unchanged. — Indigo-hlue. Yelloios. A portion is tesued for ferric oxide by means of potassium ferrocyanide ; another part is tested for picric acid by means of ' F. Pol, 1874 : Bing. pol. Jour., 212, 520. FOL'S METHOD. 193 potassium cyanide solution. The produetion of a, blood-red color indicates piei'ic acid. If the colors do not appear, another portion is treated with a boiling solution of 1 i)art uF soap in 20(1 parts of water. («) The color changes to brown, Init becomes yellow again with an acid. — Tiinner'n-. (b) The color becomes voi-y dark. — FitHtlo. (c) The color remains nni'haiiged. — Weld. Perslanherries, Qiicfcitrin. Another portion is boiled with stannous chloride. («) The color remains nnchanged. — i^nvrc'iti-lii . (h) The color chauges to orange. — I'ers'ian hcrries. If annatto is the coloring matter present, the color changes to greenish-blue on boiling in concentrated sulphuric acid. Reds. The substance is treated with Imiling soap solution. ((') The color is entirely discharged. — Hnif'roii-earraine. (h) The color is slightly discharged. — Anil ine-red. (c) The color changes to yellowish-i-ed or yellow. — Brazil- ivood or Coeliiiieal . A poi'tion of the sulistance is treated with concentrated sidphuric acid. (1) A cherry-red color is produced. — BraztJ-irood,. (2) A yellowish-orange color is produced. — Coeliineal. id) The color remains unchanged. — j\Ladder-Ted . This col- or is not dischai'ged l>y ammonium chloride, or by a mixture of equal parts of stannous chloride, hydrocldo- ric acid, and water. Oreens. May consist of blues and yelh.iws in mixture, or of such sub- stances as aniline-green. The substance is heated on the water-bath with alcohol of 95 per cent. (I.) The alcoliol is colored yellow, wliile the substance l)e- comes moi'o ami more blue. — Ind'itjd or I'nixsiaii- hhie is presi-nt. The residue is_ washed and tested for these blues, as already di- rected. The alcoholic liquid is tested for yellows as abo\e. (II.) Tlie alcohol is colored green, wliile the substance be- comes less colored. — Andine/j/reii or a mixture of aniliiie-hlue with yellow is present. A part of the substance is boiled with dilute hydrochloric acid. 194 COLORING MATERIALS. (a) The liquid is colored blue or lilac. — Anillne-grmn from methyl iodide is present. (5) The substance is decolored. — Atiiline-green from alde- hyde. (c) The substance is colored blue, while the liquid becomes yellow. — A niline-hlue mixed with yellow. Violets. The substance is boiled in calcium chloride solution. {a) It is unchanged. — Alkainia-vioh't.' (b) It is coloi'ed nankeen-yellow. — Madder-violet. (c) It is decolored. — Cochineal-violet. Another portion is boiled in citric acid : the color is lightened. — Aniline-violet. To distinguish between the two aniline-violets, a third part is boiled in hydrochloric acid, which is diluted with three times its volume of water. After washing it apjjears blue-violet if ordinary aniline- violet is the color, while if Hof- mann's violet is present the substance appears greenish, and after washing light lilac or bluish. ' [AUcanet. The root of Anehusa tinctoria. A red color, termed alkanin, or anchusin. Used to color pomades and oils. Insoluble in cold water, soluble in alcohol, ether, benzene, petroleum benziii, carbon disulphide, fat oils, and essential oils, the resulting solutions having a red color. The fixed alkalies dissolve it with a blue color, sometimes used to color syrups. On neutralizing the blue alkaline solution, the alkanin is precipitated, red to brown. Ammonia reacts with production of alkanna-green. Alcoholic solution of alkanet with stannous chloride giTOs a crimson precipitate, with lead acetate a blue precipi- tate, with iron salts a violet precipitate, and with mercuric chloride a flesh- colored precipitate.] SOLUBILITIES OF ANILINE DYES. 195 J pa > o pq I— ( o I— t W P < o o CO Is 8- ki _>J. ■ p tJ 1 QJ II ^ CO - i * -q s s 1 5 = - c "tJ 41 a in : D 03 K K , "« "o s f 01 ,0 § « ctf si ? e a - 03 OS a 1 X! S 1^ Q 03 s a tJJ ai 0-j u t- GO m p rrj CC p"" <1 ^ s 2 S £> 3 3 X] 1 TJ U C ~~P ■^'tL 5 |-^ g £ - S !.. fl li "o ;/j 1 ■II '~ B d 3 < ^ '5 So" „ 11 il i3 1=1 S 1 = u g (3 " 1 PC^ ' t- 5 _ ^ _ >i == ^ :3 jj s ^"0 >1 >. 0^ > 3 '{■' 03 (B K i s ::: ££ ft P "C P s "u. g e s P r^i 5 1 6 - a 5 - : 3 - 'fc^ E d 3 1 OS ; - 2 _ S;S >1 "o f 1 M W u\^ ^ •s i-T C tLaa •c £0 g ™ .2 1 w t. ^ 1 Is >1^ c '3 t-j 1 '0 a] til I s 0/ ^ ^ "3 3 w id 1 3 "p E S ru £2 a i i c "o "c-^ i t- S a) a s c 1^ "3 < p a 'S u 'p '5 -^ -5 ^ -1^ f*. n a 196 COLORING MATERIALS. ^■ _ ■f:_^ _ ^■ -^ > _. i-= _^ r; -^ = i; i c'~ -e'^ S.z s b e. 1 .§-r ?~ ■-;n ^■5 4^ ■-"2 l£ 'S, '^, g 'tH 1^ 'Si X ? X ,^ 0^ p« (K^ rn:^ rjb £> b_-; 5 ■7 £ j_- s '£ '1 s f i.- ^ N jz: = || ^ ^ -■ i^-^ S c ^ % ■^ ^ — +.; t- S" > tL „_5 ■1. ^ iX ~ c3 'i c P ^"3 H ^' fi ^ K a5 7: ft c -i P X C _ _ a. & S^ 5 ■^ t: _C v' > i? Pi £.i _c < ^ r^ a i g '0 ^ ^ a 'A s S;^ _ 3 ^ s t-i T 5-I ?^ c >^ — CO < 1^ >1 p 'c VJ S '0 CD H E- ■ . ti >! txr 'S I2 a Ph K 'I. "T 3 "H C r^ -^ ? P -^ 5 -^ ? rt ■= c — rt .9™ X - ^ ^ ■- ^- ^ "J:; .z 7 i 3 "7 5 3^ ■c ^ X-'-9 K a5 s^ P a. 5 P ■5 -X 1^ > c tx GJ tt, a: (^ ^ 3 ■T '3 tr P - - ^'3 'E~ fl _ S 'j=; ^ 5 ro i-i L c ^ -2 ^' s^ p - -1 1 « ■-■« ^ " ^■7 S "c c "t:^ i^'-S K M W C^ Tfl l« s P P CO 'r '-' i 5 _s = Tl 1 t- -^ '1 1 _^ i s n V. 1^ s ^ < -^ -< < REACTIONS OF DYES. 197 "^."S "o V O PH el -< & P CO >^ P O CO O O /, i => ^ 'z^ C— ' K3 S -:^ M n C^ S-3 C -r; ^ r, =; -J r — — ^,^ '-I ^ "^ 7J v • "o ^ "o ~ p P3 - .; rt c > -^, i5 g 9-3 5 p_3 198 ELEMENTARY ANALYSIS. CONCH AIRAMINE, CONCUSCONINE. See Cinchona Alkaloids, p. 92. COTTON-SEED OIL. See Fats and Oils. CREAM OF TARTAR. See Taetaeic Acid. CUPREINE. See pp. 92 and 153. CRYPTOPINE. See Opium Alkaloids. DYES. See Coloeing Materials, p. 181. ECGONINE. See p. 172. ELEMENTARY ANALYSIS of Caebon Compounds.— A qualitative analysis for the organic elements, C, H, and E", is only made for the purpose of determining whether a carbon compound be present or not, or whether a given or- ganic compound be nitrogenous or not. In the case of bodies not rapidly volatile, (1) ignition in the open air, either on platinum foil or in a glass tube open at both ends, will show carbonization in case a carbon compound be present. The fact of carbonization is shown first by the appearance of a black resi- due, and then by its gradually burning away. In the case of volatile bodies, or when for any reason the result of simply ignit- ing the body by itself proves uncertain, a resort is had to (2) igni- tion with copjper oxide in a small comhustioiv-tuhe, with tests of the gas evolved. The dry substance is mixed with an excess of copper oxide (previously ignited and cooled), the mixture intro- duced into a small tube of hard glass, the tube being closed at one end and fitted at the other with a tubulated cork carrying a small glass tube bent at right angles. On applying heat, very gi-adually, to the combustion- tube, the resulting gas is passed into lime solution or baryta solution. If a precipitate be formed this is to be gathered in sufficient abundance, and its solubility in acetic acid with effei-vescence is tried, for the identification of carbon dioxide. Meantime it is observed whether there be con- densation of liquid in the bent tube or not, and droplets so ob- tained may be tested, with anhydrous cupric sulphate, for water, as evidence of hydrogen. But this evidence is dependent upon the absence of moisture or hydrates in the contents of the com- bustion-tube. Unless the result of the simple test just men- tioned be clearly conclusive, it is better to use the safeguards ELEMENTARY ANALYSIS. 199 against moisture directed for Quantitative estimation of carbon and hydrogen. Tliat is, tlie substance and the copper oxide are properly dried and secured from tlie moisture of the air, and the ail- in the tilled combustion- tube is replaced by dried air, before the combustion. Then the combustion is conducted very slowly, and the small conducting tube is kept cold. — To be certain that carbon dioxide obtained by ignition does not come from carbon- ates — that is, from non-alkali carbonates or alkali bicarbonates — the material is first to be tested fur carbonates. If these are present, enough of hydrochloric or sulphuric dilute acid is add- ed, and the material dried again. If it be found that a carbon compound be present, to find whether it be a nitrogenous compound or not, it is sufficient, in the greater number of cases, (3) to heat tlie dry nuhstonoe, well mixed with dnj voihi-liine, when the nitrogen is g[ven oif in the form of ammonia. The heating must be to redness, and thorough drying of the material, as well as previous ignition of the soda- lime, render the operation much more convenient. An ordinary test-tube may be used for this combustion ; but a section of com- bustion-tubing, of hard glass, with one end closed, serves better. The tube may be wrapped in a strip of copper gauze near the open end, and held by the forceps, while the heat of the flame is very gradually applied. The test for ammonia is made by moist- ened red litnms-paper, also by the odor, and the color given a drop of dilute solution of copper sulphate held on a loop of pla- tinum wire. Bodies rich in nitrogen give the (xlor of singed hair when merely burned in the air. Heating with fixed alka- lies does not cause the production of ammonia from the nitrogen of all organic bodies. Some bodies so treated yield vaporous alkaloidal compounds, mostly showing the alkaline reaction to litmus, but not exhibiting other chai-acteristics of annnonia. Other bodies, as many of the nitro-compounds, when treated by combustion witli fixed alkali, give no indication of the presence of nitrogen. For these it is necessarv, and for all it is sufficient, to (4) heat the snh.stniice mlth a frdijinent of mctnlliti jyotassiaiih for some time (Spica, iSSn), and then test the mass for cyanides. " The fused mass is digested with hot water and a ferrous salt, acidulated, and a drop or two of ferric salt solution added. The blue color of ferric ferrocyanide gives evidence of nitrogen in the material taken. Also the test may be made for production of sulphocyanate by digesting tlu' mass (after fusing with the potassium) with ammonium sulphide, and then acidu- lating. A qualitative examination for liidphur, phosphorus, sele- 200 ELEMENTARY ANALYSIS. nitnii, and arsenic may be made by applying a strong oxidizing agent, and then testing for sulphuric, phosphoric, sek'iiie, and arsenic acids. Tlie material (free from the acids last named) is either digested with strong nitric acid (sp. gr. 1.4^) or smelted with ])otassiuin nitrate, afterward treated with water, and the fil- trate tested for the acids. For arsenic the material may be treated, as in the examination of animal tissues for arsenic, by drying, (Hgestiiig with concentrated sulphuric acid aiul repeated small additions of nitric acid until tlie carbon compounds are oxidized, and the nitric acid then wholly expelled, afterward neu- tralizing with magnesia, and subjecting the filtrate to Marsh's test for the arsenical mirror. Arsenic will sometimes be found by igniting with sodium acetate, when cacodyl compounds are revealed by their odor. Phosphorus may usually lie found by heating the carbonized material with powdered magnesium, inti- mately mixed, in the bulb of a reduction-tube, after whicli phos- phorescence appears in the dark. For fliioriiie, hraiiune, and iodine, as elements in an organic compound, it is necessary to effect such a decomjiosition as will bring the chlorine, etc., into union as chlorides, etc., tir into the elementary form. Thus chloral, chloroform, and other similar compounds do not react with silver nitrate to form silver chlo- ride, etc. Tlie necessary liberation of the haloid elements is ob- tained in some cases by digesting with str(mg potassium hydrate solution, in other cases by igniting in mixture with an excess of lime (each (jf known purity), after which the aqueous filtrate may be acidified with dilute nitric acid, and treated with silver nitrate solution for precipitates. See further upon the quant itutioc de- termination of tlie halogens. Tu renarve i!. Finally, in cpialitative analysis for the elements in a portion of organic matter, instead of the direct examination for these elements, aliove described, the analyst will most oi'fen determine at once what organic compounds hnoicn in ehemintrij he has in hantaining the quantitative composition of organic b(.)dies, from the first estal)lishment of chemical science to the presont time.' For nitrogen, eitlier an 'Lavoisier, 1781-17^4: burninc; ot the sulisliiiicc willi a iiR'iisiin'(t voliiino of oxygen, and mciisurement of tliu volume ol' iMi-bon dioxide produred, for eal- culation of weiglit: Mfm. Arad. Sci., 17H't-.S7. Berthollet, 1810: J/i'm. di' Vhiatitut Nalumal, ii, 121. Saussure, 18(17-1814: Ann. Chim. /'hi/.^., 62, 225; 78, 57; 89, 27:i. Gay-Lussac and Thenard, 1810-1810: use of eldoviUe 202 ELEMEN TARY ANAL YSIS. ignition with lixed alkali is made to jaeld ammonia for determi- nation, or, more often, combustion with its products carried over heated metallic copper is made to furnish free nitrogen for measurement. The oxygen is obtained by difference. Methods for direct estimation of the oxygen have been proposed from time to time, as briefly indicated in succeeding pages, but none of them has come into actual use. The supply of oxygen for combustion is obtained as follows : (1) From coi^per oxide. This is either granular or in powder, coarse or fine. It is made by heating copper turnings or copper scale with nitric acid, finally to ignition, or by igniting copper nitrate prepared for the piirpose. The granular form is obtained by incipient fusion. Both granulated and coarsely powdered copper oxide is to be of uniform size, by sifting, free from dusty oxide. For most uses in the combustion-tubes, the granular form moderately coarse, or that from the turnings, or the coarse powder is to 1 )e chosen, in preference to fine powder. That is, the column is to be sufficiently permealjle by gases, so that it will not be necessary to have a channel over the oxide, in the tube. To intermix with the substance under analysis finely pul- verized oxide is sometimes employed, or obtained by trituration of the granular form during the intermixing. Oxide of copper, when heated, must evolve no nitrous fumes nor carbon dioxide. It is hygroscopic to a considerable extent, and in combustion for carbon and hydrogen it must be absolutely dry. For nitrogen determinations it is desirable to have it dry. It may be ignited, in a hessian crucible, short of incipient fusion, and when still warm put up in a flask with a neck a very little wider than the combustion-tube, and closed by a perforated stopper bearing a drying-tube of chloride of calcium. Also, it may, with advan- tage, be dried by ignition in the combustion-tube, in a current of dried air. This may be done when the oxide is to be after- ward removed from the tube to the flask in preparing tlie sub- stance for combustion, and it may with still greater advantage be done when the substance is burned in a boat. In use copper oxide is reduced to cuprous oxide or to metallic copper. With as source of oxygen and introduction oi; copper oxide, also the determination of nitrogen: Ann. Chiin. Pfiys., 74, 47; Schweiger's Journal, 16, 16. Doberbi- NER, 181G: Schweiger's Journal, 18, 379. Bbrzelius, from 1814; the use of horizontal combustion-tubes of glass. Liebig, 1831 : combustion with copper oxide, in detail nearly the same as " Liebig's method" sometimes employed at present: Ann. Phys. Chem. Pogg., 21, 1 (application to cinchona alkaloids). Brunner, 1838; oxygen gas supplied for combustion: Ann. Phys. Chem. Pogg., 44, 138. Bunsen: intermixture with copper oxide in the combustion- tube. ELEMENTAR Y A NA L YSIS. 203 tlie sujtply of oxygen gas at tlie close of combustion, tliu I'educed copper is restored to oxide. Otherwise it may be restored by adding nitric acid, heating, and igniting. — (2) From lend chro- inate. This must contain nothing st)lnble in water, and yield no carbon dioxide when heated. It fnses at a red heat. It is pre- pared by melting in a hessian crucible and pouring out upon a stone slab, when it is pulverized moderately tine, sieved, and bottled for use. Or the melted chromate may be poured into water in a copper vessel, and the granulated mass collected, dried, and pulverized. It is not hygroscopic. In melting it adheres to the combustion-tube. In use it is reduced to the green chromic oxide with lead oxide. To use it a second time it is roasted, fused, and pulverized. After the second time it rec^uires oxidation, by digesting the j^owder with nitric acid, drying, fusing again, and powdering. — Lead chromate is em- ployed instead of copper oxide when sulphur, or selenium or tellurimn, is present ; also, when very difficultly oxidizable sub- stances are in hand. Its greater efficiency as an oxidizing agent lies chietiy in its being fusible during the combustion. — Mayek (ls,"i.-i) introduced into the powdered lead ciiromate one-tenth its weight of potassium dicbrouiate ])revii)Usly fused and pul- verized. This mixture serves to expel from alkalies or alkaline earths, if these be present, the carbon dioxide they may have absorbed ■ from the products of combustion. — (3) A utrcain of oxygen gns is eiiqiloijcd. This is supplied mcist evenly and satis- factorily from a pair of gas-holders, the one tilled with oxygen, and the other with atmospheric air, the stream from each being purihed by passing through at least two U-tubes, one tilled with pumice-stone and sulphuric ucid, to dry the gas, and the other tilled with fragments of potassium hydrate to remove carbon dioxide. — Also, without a gas-holder, a stream of oxy- gen is obtained by generating this element, in the further end of the combustion-tube itself, from lead dioxide, heated in an air-bath to lS0'^-2n()° (I., or by heating mercuric oxide or po- tassium chlorate by the tlame. — Oxygen is sometimes generateil in the cf)mbusti()n-tube from chlorate of potassium placed in a pla tinum boat and subjected to heat. — In the pivparation of oxygen for the gas-holder, I'lilorate of jiotussium, well mixed by tritura- tion with one-tliousandth of its wcigiit of ferric oxide (Feesk- Nius), is heated over the Hame in a plain glass retort not over half filled. Tlie heat is applied very gradually, and as soon as the salt begins to fuse the rvXort is g('ntly shaken. When the air is expelled the connection is made witii the gas-holder. If the proportion of ferric oxide be exactly adhcrcil to, the evolu- 204 ELEMENT A R Y A NA L YSIS. tion of gas will not be impetuous. lOO i;-rams of the chlorate will yield abont 2 T liters of oxygen. Oxygen gas is tested for chlorine by passing it through silver nitrate solution, and for carbon dioxide by passing through lime solution. A splinter of wood which lias been kindled an"d blown out should burst into a Hame when introduced into a stream of (ixygen gas. The .ti>i/ii-//iiie used as the fixed alkali, for the conversion of organic nitrogen into ammonia in the combustion-tube/ is a mixture of two parts of calcium hydrate with one part of sodium hydrate. It is usually made by the cvapuration of a solution of sodium hydrate with the proportional quantity of slaked lime, y. W. Johnson (1>^72^) recummends, as more convenient and even better, a mixture of dpial parts of crystallized sodium car- bonate and slaked lime, prepared by evaporating the mixture." ^(jda-liinc is olitained in granular form, more convenient for the greater part uf its uses than the powdered form. — It should not evolve any trace of ammonia when heated with sugar ; it should not be more than slightly moist ; and (unless prepared upon Johnson's direction) sliould not effervesce very much upon the addition of acids. It is made ready for use by igniting in a hessian crucihle at a gentle heat, and while warm it is put up in a well-corked bottle, or a bottle with a tubulated stopper carrying a drving tube containing both calcium chloride and a little gran- ulated soda-lime. lletdJlic. rapper is used, while heated, to reduce oxides of nitrogen in the combustion-tube, this being necessary, first, to prevent error in estimating carbon by the aljsorption of carbon dioxide ; second, to avoid loss of nitrogen in estimating this ele- ment by its volume when free. Coils of copper gauze or foil, or spirals of copper wire, are heated to redness in the air long enough to oxiilize the surface, and then heated in a stream of hydrogen to reduce the oxide formed. For the reduction the coils are introduced intrj a combustion-tube having a tubulated stopper at each end, and a current of hj'drogen passed through ' Varhentbapp and Will. 1841: xinn. Chinn. Flxar.. 39, 257. "^ Am. (Jiemint. 3, IGi ; ISTO: Am. diem. Jniir., i, 77. 3 " Equal weinht'^ of sal-soila, in clean (washed) large crystals, and of good white and promplly-slaking quicklime, are separately so far pulverized as to pass holes of ^\ inch, then well mixed logdher, placed in an iron pot, which should not be more than half filled, and gently heated, at first without stirring. The lime soon begins to combine with the crystal waicr of the sodium carbonate, the whole mass heats strongly, swells up, and in a short time yields a fine pow- der, which may be stirred to effect intimate mixture and to dry off the excess of water, so far that the mass is not perceptilily moist, and yet short of the point at which it rises in dust on handling. When cold it is secured in well closed bottles or fruit-jars, and is ready for use" {where last above cited). ELEMENT A RY ANAL) SfS. 205 iintil the air is expolU-d, when heat is apphed as the stream of liydniijeii cuntiimes. Coarsely granulated eii[)per oxide, reduced by ii;iiition in a current of hydro- gen, is employed to some extent instead of the s|)iral coils, and is more efficient than they. All copper reduced hy ignition in a stream of hydrogen is liable to Contain traces of occluded hydro- gen, from which error may arise unless precaution be taken.' At ordinary teniperatui'c it quickly absorbs moisture from tlie air. Ci'jii>i'i' (jiime iinil uv'iv are also used in the combustion-tube in methods of condjustion of non-nitrogenous bodies, reipiir- ing only to be cleaneil by a mo- mentary ignition in the clear flame before use. Siihitian of J'otiiKsiuiii Hij- (li'Ktc. To absorb carbon dioxide in potash bulbs, g(.)od potassium hydrate nearly free from carbo- nate is dissolved in an e(pial ^veight of water. Si.nne chemists use a solution in 2 parts of water ; others a solution in | jiart of watei-. The solution drop])ed into diluted mineral acid slionld not effervesce. It sliould be strictly free from nitrite. It is sometimes used a second time. — Sobd hydrate of p{.)tassinm is also employed for absorption in clemeiitaiT organic analysis, taken eitliei- in stick or in lump, the drier the better. Chhiridi' (if (Jdlciiiiii. For absorption of the water i-esulting froin combustion, dried cdlcluiih cliJoridr strictly free from alka- ' G. S. Johnson, 1870: Jour. Cliem. !~ioc., 29, ITS. 2o6 ELEMENTARY ANALYSIS. line reaction is employed. In preparation the solution is stirred while evaporating, to granulate, and the residue dried at about 200° C. It consists of CaCl2.2IIoO. The granulated form is much preferable. It may be tested, in concentrated solution, with litmus-papers. It may be prepared from crude fused cal- cium chloride by dissolving in lime solution, filtering, neutraliz- ing with hydrochloric acid, evaporating to dryness, and heating as above directed. But to be well assured that the calcium chlo- ride is free from uncombined bases, the operator should take the precaution to pass dried carbon dioxide through the Ulled chlo- ride of calcium tube for an hour or two, and then a current of dried air to restore the normal weight of the tube. — For drying gases the crude, fused calcium chloride, in broken masses, is all that is required. It usually has an alkaline reaction. Combustion- tubing is to be of hard potash-glass, mostly of 12 to 14 millimeters (y^ to -|- inch) inner diameter, and about 2 millimeters (not quite \ inch) thickness of glass. It is best obtained in lengths sufficient for two tubes — that is, in pieces mostly b^ to 6|- feet long. For many purposes the combustion- tube is drawn out at one end, and preferably in bayonet form, as in Fig. 9. A section of tubing long enough for two combustion- Eig. 9 tubes is readily so drawn and bent that when severed in the cen- tre the two finished tubes are obtained. The edi'i'])arati()n tVirit. The sources of error are so many that even an experienced operator, when commencing work with newly collect- ed appliances, is quite liable to failure. When the woi'k is well in hand, and ()])erations upon material of known composition are made to succeed each other \vith almost invariable success, an imjxirtant estimation may be undertaken with cnufidence in the I'csult, but tliis is to be obtained as the mean of several nearly coinciding determinations. Es'iniATiox OF Carbon and Hydrogen in BfmiEs not con- TAiMX(i Nrri;2) ; then the air is turned off, the roll of metallic copper \v;irm from the drying-oven intro- duced into its place, the platinum boat with the substance inserted, the connections made, and the combustion conniienced. The stream of air is not changed for one of oxygen until the continu- ance of the combustion demands it; and neither is used in such excess that the metallic coi)i>er becomes oxidized before the nitro- 220 ELEMENTAR Y ANAL YSIS. gen luis all passed out. To burn out the last traces of carbona- ceous i-esidue the stream of oxjgen may be used freely. The roll of metallic copper is used but once. Estimation of Nitrogen in' Cakbon Compounds. — Absolute detertn) nation hij vol nine of the gas. Of various serviceable methods for this estimation, the following are here presented : Method of Johnson and Jexkins,' based in good part upon Dnmas's iMethod. — The substance is burned in mixture with coppei- oxide, and, by help of oxygen generated from potassium chlorate, put in the rear of the combustion-tube, the gaseous pro- ducts i)eiug all carried through a porous column of heated metal- lic c(jpper of leu.gth sufficieiit not only to deoxidize nitrogen oxides but to absorb all the excess of oxygen. A short layer of heated copper oxide, front of tlie metallic copper, oxidizes any hydr(jgen held occluded by the metallic copper, also traces of carbon monoxide formed by the metal. The gases are received in a measuring-tube (azotometer), over potash solution, which they ])ass through, and which absorbs all carbon dioxide, nitrogen being left alone as a permanent gas, measured for quantity. Between the combustion-tube and the azotometer is introduced a mercurial air-pump, by which the combustion-tube is first fully exhausted of air before the combustion, and by which the gaseous products left in the tube after combustion are drawn out and delivered to the azotometer." During the combustion the gases pass through the pump to the azotometer. After the initial ex- haustion of the combustion-tube, carbon dioxide is generated in it by heating a short column of sodium bicarbonate placed in the very front of the tube, this carbon dioxide, like that formed in ' R. W. Johnson and E. H. Jenkins, 1880: Am. Ghem. Jour., 2, 37; Zeitsch. anal, Chetit., 21, 274; Chem. News, 47, 146. A valuable report on Prof. John- son's method is given from continued experience in its use, in comparison with the Ruffle Method, by C. S. Dabnev, Jr., and B. von Herff, 1885: Am Chem. Jour., 6, 234. Also, valuable improvements in the pump, and a modification of the charging of tlie combustion-tube by T. S. Gladding, 1882: Am. Chem. Jour., 4, 42 (illustrated). The '• Official Methods of the Association of Agri- cultural Chemists for 1886-7" are given in Bulletin No. 12, Department of Aff- ricuUure, Washington, 1886, p. 52. Modifications of Dumas's Method are also given by G. S. .Johnson, 1884: C/iem. News, 50, 191; Jour, Chem. Soc., 48, 189; and by Ilinski (with ordinary laboratory apparatus), 1884: Ber. d. chem. Qes., 17, 1347; Zeitsch. anal. Chem., 2^, 76. 'Dabney (see last foot-note) says: "For getting the air, before combustion, and the nitrogen afterward, out of the tube, we have used carbon dioxide with- out a pump and have obtained excellent results. . . . Magnesite or manganese carbonate, put in the back end of the tube, are the best sources for this pur- pose. [See, following, Simpson's Method.] But more time is consumed in this way than with a, good, fast-working, tight pump." ESTIMA TION OF NITROGEN. 221 taken np in the 'di' is directed azottinieter Ity tlie potash combustion, bt solution. The_ roj>pcr n.vid,- is directed to be made by Jieatiiii;- copper scale witli 1(1 per cent, of potassium chlorate and eiir until tlie mass does not ul,,\\- when stirred. The potassium chloride is to be washed out by decantati.m, and the coppei' oxide dried and mode- rately ii,niited. Metidlic copper is used as hue copper izanze in rolls to ht the combustion-tube, or as granular oxide of copper reduced and cooled in a sti-eam (jf hydrogen (p. 2(>5). l\iii(^Hiuiii eJilonde is prepared by fus- ing the coniniercial article in a porce- lain dish and pulverizing wdien cold. iSodnim hivarhomite is used, and must be free from organic matter. Solution of jiotosKd is made l)y dissolving com- mercial ]iotash in sticks in less tlian its weight of watei-. and permitting the excels to crystallize out when ' cold. The same solution max- l)e used a num- ber of times. — 71ir coiidiiistioii-ttdje, of best hard glass, should lie ahout 2S inclies (71 centimeters) long. Tlie rear end is bent and scaled as^ in Fig. 20. It is best to ])rotcct the liorizontal part with thin sheet coppei' or coj)per gauze, as directed fui-tljci- on. 77/r azoio'ini;t<'i\ Fig. is, is a modi- fication of Scniji-F's.' The gas is mea- sured in an accui'ately calilirated bu- rette. A, of 12(1 c.c. ca]iacity, graduated to fifths C.C., and closed at the upper end by a The lower end is connected, by a pertVirated stoppei' about If inches (\.U centinictei-s) long and \\ inches (3.s centimeters) in diametej-, with another tube, which has two arms, one, D, to receive tlie delivery-tul^e from the ]uimp, the otlier to ci.nniect by a rubber tube with the bulb, F, of 2(H) c.c. ca}iacity, for the supply of [Kitasli solution. The burette is enclosed in a water- jacket of about ^\ inches {\X> centimeters) external diameter. Its lower end is closed by the ruliber stopper that connects the burette with the two-aruieil tube below. The upper end of the ;lass sto]i-cock. ' 1868: Zeitsch. anal. Chem., 7, 4:i(). See :iUo ihlil , INWI : 20, 257 222 ELEMENT A RY ANAL YSLS. H jacket is closed by a thin rubber disk slit radially and having four perforations : one in the centre admitting the neck of the burette, and three others near the circumference. Through one of the latter a glass tube, L, bent as in the fig- ure, reaches to the bottom of the jacket, another short tube passes through the disk (these tubes conveying water to and from the jacket), and the third "hole supports the thermometer. The azotometer is held upright and firm on a stand by rings fitted with cork wedges around it. The bulb for the potash solution rests in a slotted sliding ring. The air-pump'' used by Prof. Johnson is a Sprengel mercury-pump, modified so as to be easily constructed and durable. It is shown in outline, with some parts enlarged, in Fig. 19. Tlirough a rubber stopper wired into the nozzle of the mercury reservoir. A, passes a glass tube, B, 4 inches (10.2 centimeters) long, and this connects by a stout rubber tube, C, with the straight tube, D, 3 feet (91.4 centimeters) long. The stout rubber tube, E, 6 inches (15.2 centimeters) long, connects D with a straight glass tube, F, of about the same length as D. Gr is a piece of combustion-tubing, IJ inches (3.8 centimeters) long, closed below by a doiibly perforated soft rubber stopper admitting the tubes F and H, and above by the singly perfo- rated rubber stopper into which the tube I is fitted. The tube H has a length of 4.5 inches (114.3 centimeters). At the bottom it is con- nected by a fine black rubber tube (previously soaked in melted tallow) with a straight tube of 3 inches (about 7 centimeters), and this again in the same way with the tube K, of 7 inches (about 18 centimeters) length. The tubes H and K should have an internal diameter of 1.5 millimeters, F may be 2 millhneters, and D still larger. For H and F may be used slender Bohemian glass tubes of 4 millimeters external diameter. Their elasticity compensates for their slenderness. If heavy barometer tubes be used the stoppers and G must be of correspondingly larger dimensions. The joints at G must 'A mercurial pump Tor nitrogen is also figured and described by Dabney, 1885: Am. Ghem. Jour., 6, 236. Hg,19 ESTIMA TION OF NITROGEN. 223 be made with the greatest care. It is best to insert the lower stopper for lialf its length into G, and F and II should tit so snugly as to be inserted with effort when oiled. The tube I must be of stout glass, about a centimeter (0.4 inch) in diameter, and drawn at both ends to a gradual tajjer, the outer end bent to connect with the combustion-tube, the inner end when oiled turned into a perforation of about 0.5 centimeter (0.2 inch) in the upper stopper. The joints entering Gr are the only ones having to resist pressure into vacuum, and they must be made with the utmost care. If not secure without, they are to be trapped with glycerine. To do this pass F and H through a stopper of J inch (or 13 millimeters) greater diameter than G and placed below it, when, before inserting I, a jacket-tube 4 inches (10 centimeters) long is htted upon this stopper, surrounding G. After I is in- serted the trap is ready, to be filled with concentrated glycerine, which is preserved from dilution by adding a stopper to the outer tube, around I, split in halves for adjustment. — The two rubber tubes are both provided with efficient screw-clamps to govern the flow of mercury. — The tubes D, F, H, and I are secured by cork clamps and wires, or otherwise, to an upright plank, which is framed below into a heavy horizontal wooden foot on which rests the mercury-trough. The plank carries above a horizimtal shelf for the support of the reservoir, A, the neck of which rests in a perforation in the shelf. At the fastenings of tlie tubes upon the upright support thick rubber tubes are interjtosL'd as elastic rests. The rubber tube joints should be wound with waxed silk. A glass funnel is used in A to prevent spattering of the mercury. |kCI03 1 MiyJURE I RINSINGS! Cu. jCuOJ pQa [ASBESTOS I I i a cm.' 30 cm. I 8 c m. 12 cm.|scm.|3cm{ lOcm. 9 Fig. 20 The comhitfition-tuhe is char(/etl as follows : Of the potas- sium chlorate from 3 to 4 grams, according to the amount of carbon to be burned, are placed in the tail of thetulie, Fig. 20, followed by a plug of ignited asbestos just at the bend. Of the substance under analysis D.d to 0.8 gram, from the M'cigiiing- tube, is well mixed in a mortar (previously rinsi-d witli tJie copper oxide) with dry (reiM^iitly ignited) o.xide of copper enough to fill 11 or 12 inches' (2S-30 (•ciitiim'ters) of the tube, and the mixture introduced through a funnel. The rinsings of the mor- 224 ELEMENTARY ANAL YSLS. tar with oxide of copper are added to fill about 3 inches (7. 6 centimeters) of the tube, and a second asbestos plug placed. On this is placed the reduv^ed copper for 4 or 5 inches (10 or 12 centimeters), then a third asbestos plug, then 2 inches (5 centi- meters) of the copper oxide, and a fourth plug of asbestos, fol- lowed by 0.8 to 1.0 gram of the sodium bicarbonate.' The re- mainino; space is loosely filled with asbestos to take the water of combustion and prevent it from fiowing back upon the heated glass. The anterior part of the tube is wound with copper foil, leaving the rear of the metallic copper visible. The filled com- bustion-tube is placed in the furnace, on a level with the tube, I, of the pump (Fig. 10), and carefully connected with the latter by a close-fitting rubber stopper moistened with glycerine. — The (i::i)toinete)' is pre^jarcd and testeil as follows : The bottom is fill- ed with mercury Xo about the level indicated by the dotted line G (Fig. 18 ). The arm D is securely closed by a rubber stopper. The st(]})-c(.>ck FI is greased, the plug inserted, and the cock left open. The potash sohition is poured into F until A is nearly full, and some solution remains in the bulb F, which is now raised care- fully in one hand, while the other hand is upon the stop-cock H. When the solution has risen in A very nearly to the glass cock, the latter is closed, avoiding contact of the alkali with the ground glass bearings, when the bulb is replaced in the ring and lowered as far as may be. If the level of the solution in the azotometei' does not fall in 10 or 15 minutes, it is tight. — The jmmj) is set in ojieration hy putting its deli very -tube K in a trough of mercury, supplying the reservoir, A, with at least 500 c.c. of mercui'v, and cautiously opening the clamps C and E. If the mercury does not start at once, repeatedly pinch the rub- ber at E. It should flow nearly as fast as it can be discharged at K, and without filling the cylinder G. A complete exhaustion 'Gladding (1883: Am. C'lipin Jonr., 4, 45) dispenses with chlorate of pot- ash, and puts aljoutO.ti yram bicarbonate of soda in the tail of the tnbe(l). The space 2 is filled with about two inches of ignited asbestos. The substance at 3 is mixed with copper o.^cide, a'^ fine as sea-sand, without dust. At space 4 is another 0.6 gram of tlie bicarbonate ; then is placed a layer of copper shot, and again a layer of coarsely granulated copper oxide (6). The analysis is begun by drawing the potash solution nearly to the top of the azotometer, then turning up lamps under (I, and at the same time starting tiie pump. When a perfect vacuum has been obtained and the copper oxide (6) is red hot, the lamp just beyond 1 is turned up, and a gentle heat, just sufficient to drive off the carbon dioxide from it and not \,o heat space 3, is applied. When the tube is full of carbon dioxide this lamp is turned off and the tube again exhausted. By this process of washing out the tube several tenths of a c.c. of additional gas are obtained and almost the last traces of air removed. On running the heat back the liicarbonate at 4 gives off carbon dioxide, and refills the tube before the cojnbustion of the substance at 3 begins. ESTIMA TION OF NITROGEN. 225 of the combiistion-tube can generally be obtained in 5 to 10 minutes' working of the pump. If the mercury becomes ex- pended before the desired exhaustion is obtained, the clamp C is closed and the mercury returned to A. Ci)nipletc exhaustion is denoted by a clanking or rattling sound of the falling mercury, and a half a minute after this is heard the clamp C may be closed. If the mercury column in II remains stationary for some minutes, the connections are tight. The mercury trough is closed and the tube K placed in a capsule. — Before conneding the azoto- 9/iete/\ heat is applied to the part of the combustion-tube contain- ing the bicarbonate of sodium. Water-vapor and carbon dioxide are evolved, filling the vacuum in the pump and displacing the mercury in the tube H. The azotometer is placed at hand, its bulb F is taken from the ring and supported in a box near the level of the tube D, the stopper of which is now removed with- out greatly changing the level of the mercury (G). The tube D is filled half full or more with water. As soon as the mercury has fully escaped from the pump-tube K, this is inserted in the azotometer-tube D. A few bubbles are allowed to escape through the water, and then the tube K is passed down so that the gas escaping from the pump enters the azotometer. It will facilitate the delivery of the gas if the extremity of the pump- tube just touches the inside of the azotonieter-tul^', as near as possible to the surface of the mercury. The carbon dioxide is absorbed in passing through the caustic potash solution, and no permanent gas should be obtained. In spite of all precautions very minute bubbles of permanent gas will occasionally ascend, but, as will be seen on observing the amount of potash solu- tion so displaced, the error thereby occasioned is extremely small. Ill the Gombnxtinn the anterior cupric oxide is first heated to full redness, and tlien the metallic copper. Then the com- bustion of the substance is steadily carried on, so that the flow of gas into the azotometer is about one bubble a second, or a little faster. When tlie horizontal part of tlie tube has all been heated, and the evolution of gas has nearly ceased, _ tlie potas- sium chlorate is lieated so as to boil vigorously with genera- tion of oxygen. Any remaining carbon (if the substance now biirns rapidly, and the reduced copper oxide is promptly reox- idized. When the layer of metallic copper in tlie anterior part of the tube begins to be oxidized, the generation of oxygen is stopped and the heat lowered all along the tube, keeping the metallic copper still at faint red heat. After a few minutes now the pump is started, slowly at first, having some vessel 226 ELEMENTAR V ANAL YSIS. under the azotometer-tube D to receive the mercury. A few minutes' pumping suffices to clear the tube, full exhaustion be- ing indicated as stated on p. 225.' The azotometer is now removed from the pump, the aioto- meter-tube D is closed by its rubber stopper, the bulb (F) is raised in its ring to such a height that the potash solution in it is nearly on a level with that in the burette, the filling-tube L is connected with water-supply, a thermometer is inserted in the top of the water-jacket, and the water allowed to run until the temperature and the volume of the gas are constant. The level of the solution in the bulb is now accurately adjusted to that in the burette, and the temperature and the volume of the gas are read, as also the height of the barometer. — When 60 per cent, potash solution is used no correction for tension of aqueous vapor is used by Prof. Johnson, following the authority of SCHIFF.^ The volume read off is reduced to volume at 0° C. by divid- ing by 1 -|- (degrees temperature C. observed X 0.003665). That c.c of observed volume , j. „o /-> IS, , — — ^-j , -— = TZ7777ZT = c.c. volume at L'. ' 1 + (observed temp. (J.° X 0.003665) The volume at observed barometric pressure is reduced to volume at 760 inilHiaders barometric pressure by the (inverse) proportion, 760 : mm. of observed pressure :: c.c. observed vol. : X =: c.c. at 760 mm. At 0' C, and 760 mm. bar., 1000 c.c. of (dry) nitrogen weigh 1.25616 grams. The corrections, therefore, may be stated : mm. bar. X 0.001L>562 • W 4^ 1 ^rr.. (1 + 0.00367 T) 760 = ^''''™ ^^^^ "•''■ temperature. The value of this fraction is given in a table for T 0° to 30", by J. T. Beown: Jour. Ghem. Soc, [2], 3, 211; Wuffs's Diet. Chem., vi. 1-17. Correction for temperature, pressure, and water-vapor tension is made by the formula : ' See Gladdins, under p. 324. 'Hugo Schiff, 1868: Zeitsch. anal. Chem., 7, 432. This author found in several determinations that air dried by passing through a 50 per cent, potash solution, at 24° C, still contained only 108 to 113 milligrams water in 19 liters. This would give to nitrogen a reading about 0.007 of its volume too high. His determinations of nitrogen, by his procedure in the absolute method, were uniformly a little too low, thus: 13.9 instead of 13.2; 31.4instead of 31.8: 9.0 to 9.1 instead of 9.1; 3.8 to 3.9 instead of 3.9. The deficiency he ascribed to retention of traces of nitrogen oxides. And the author advises to neglect the correction for aqueous vapor, in compensation for the margin of loss. ESTIMA TION OF NITROGEN. 227 P = 0.0012562 X V X -, ^ ^~^ ^ (1 + 0.00367 T°) . 760 Wherein P = the grams weight of the nitrogen measured. Y = c.c. of observed vohime. T° = temperature of the azotometer- jacket in de- grees C B = millimeters of barometric reading, f = tension of water-vapor, at T°, found in milli- meters. Of the tables convenient for consultation, to shorten calcula- tions for nitrogen, are those of BArrLE and Dancy, for use in Analysis of Commercial Fertilizers, 1SS5 : ISTorth Carolina Ex- periment Station, Ealeigh, N. C. Also, for general uses, Kohl- man und Frekichs, " Kechentafeln," 1882 : Leipzig. The correction for water vapor ten/iion is purposely neg- lected by some chemists, on the ground (already mciitioue'd) that strong potash solution leaves the gas nearly (Jrv.' On tlie other hand, the results by Johnson's procedure in absolute method for nitrogen arc more apt to be over than uiidei- tjie true quantity (see the citation from Babnky, under KuiHe's Jletlidd). "When tlie correction is required it is made as follows: Cinisiilt a table of Ten.^ion of aqueous vapor at various temperatures (this tension bein^- irrespective of pressure), and find the tension, in heiglit of mercury, for the obser\ed tenijierature. Subtract this tension from the Ijaronieter reading in the (jpcration in hand, as in the formula above. Metliod of Mil J' melt Siiiq>soih (18.").'')). — Combustion by a mix- ture of copper oxide with mercury oxide, the tube lia\ing l)ecn cleaned of air l)y a current of carbon dioxide liberated by heat- ing a carl)onate. The excess of oxygen is taken up by a good quantity f)f heated metallic copper in the coiubustion-tube; the carbon dioxide by potash solution in a receiver ; and tlie nitrogen is measured over mercury for the calculation of its weight. The mercuric oxide is to be prepared by precipitation with fixed al- kali, washing with water and then with dilute phosphoric acid, and drying at 10r)° C. — The combustion-tube, about 8(i centi- meters (31.5 inches) long, is closed in a rounded end by fusion. ' Owing to the (act tti.-it the strength o£ the potash solution v.'u-ii's, and the water-vai)or l;ension is therefore uncertain, Gai/i'erman (ISSS) collects Iho ni- trogen over potash ^olul;il)ll in a non-caliliralcd lube, llicnce transferring it to a measuring-tube over distilled water. The full tension of the water-vapor is deducted. 328 ELEMENT A R Y ANAL YSIS. A mixture of 12 grams of manganese carbonate or of magnesite, previously dried at 100° C, with 2 grams of the mercuric oxide, is introduced into the tube. A plug of recently ignited as- bestos is inserted, pushing it down to within 3 centimeters (about 1 inch) of the mixture, and next is added 1 gram of the mer- curic oxide. Of the substance under analysis about 0.6 gram is taken, from a weighing-tube, for intermixture in a mortar with 45 times its weight of a prepared mixture of -t parts of finely pow- dered and recently ignited copper oxide, with 5 parts of the dried mercuric oxide. The whole is transferred to the combustion- tube, the mortar is rinsed with some more of the mixed oxides, and the rinsings added. A second plug of ignited asbestos is pushed down to within about 30 centimeters (near 12 inches) of the iirst, leaving the mixture of oxides loose ; a layer of 6 to 9 centimeters (2J~3| inches) of the copper oxide is added and a third plug of asbestos placed ; and lastly a layer of as much as 20 centimeters (near 8 inches) of metallic copper, prepared by reducing granular copper oxide in a stream of hydrogen at low temperature (or in a stream of carbon monoxide). The com- bustion-tube is now drawn out and turned down, and connect- ed by a section of rubber tubing with a delivery -tube adapted to reach beneath the surface of mer- cury in the trougji. The combustion-tube is tapped on the table to form a channel for the escape of the gases, and placed in the furnace. — A receiver is provided, as shown, witli the trough of mercury, in Fig. 21. The receiver has about 2O0 c.c. capacity ; the glass stop-cock sliould enable it to hold mercury when tilled with it and set up in place ; a delivery-tube is firmly connected with its neck, and it is tubulated on the side near its base. This tubule carries an upright filling-tube, with contrac- tion near the tubule. It is filled with mercury, placed in the trough with the tubule under the mercur3', and about 20 c.c. of str(jng solution of potassium hydroxide passed into it. A meas- uring-tube for the nitrogen gas is represented in Fig. 22. But instead of both the receiver and measuring-tube here described, the azotometer figured on p. 221 may be used. About half of the carbonate in the posterior end of the com- ESTIMATION OF NITROGEN. 229 bustion-tube is heated, so that the air is driven out by a current of carbpn dioxide ; and at the same time a part of the tube oc- cupied by the metallic copper and the copper oxide is heated. The escaping gas is tested for air, from time to time, by receiv- ing a few bubbles in an inverted test-tube containing solution of potash ; and when the bubbles are completely taken up by the solution, and the anterior part of the tube is well heated, the deli\ery-tube from the combustion is inserted in the lateral tubule of the receiver. The substance in mixture witli the oxides is now gradually heated, beginning next the clear copper oxide, until the whole tube, except that occupied by carbonate in the I'ear, has been at full heat, and mi further delivery of gas is ob- served. Next, the remain- der of the carbonate is heated, so as to sweep out the nitrogen remain- ing in the tube. The delivery-tube is now withdrawn from the re- ceiver, which is left for an hour for the absorp- tion of the last traces of carbon dioxide. The nitrogen gas is transferred to the measur- ing-tube. Fig. 22. The stopper inserted into the lateral tubule of the receiver is moistened with mercuric cbhiride solution to prevent its carrying in air. A drop of water is placed in the measuring-tube before it is filled with mercury and inverted in the cistern. The stop-cock in the neck of the receiver is care- fullv governed t(j ol(t:dn a very gradual delivery of the gas, and is closed each time that the mercury is poured into the filling- tube, below the contraction in which the mercury is n(_)t permit- ted to fall in the l)eginning of the transfer. Close the stop-cock as soon as it is reaclied by the potash solution, leaving the ni trogen in the delivery-tube to compensate for the air it contained to begin with. For calculation of weight from volume, with corrections for temperature and pressure, see p. 226. A VERT SIMPLE METHOD FOE ABSOLUTE DETERMINATION OF NiTEOGEN, when carefully conducted, will give good results. 230 ELEMENTARY ANAL YSIS. An operation as follows, with copper oxide as the sole supply of oxygen, with SchifE's azotometer, and without a pump, will give true results, though requiring more time than the method of Johnson or that of Simpson.— The copper oxide is dried by ignition in a current of dry air in a combustion-tube with bayo- net-end. In a combustion-tube of good length, closed (with round end) at the rear, a layer of manganese or magnesium carbonate is placed first, as stated on p. 228, then a plug of as- bestos, then a short layer of copper oxide, then the substance mixed with copper oxide, mixing in a mortar or in the tube. About two-thirds of the tube should remain for the layers of copper oxide and metallic copper. The latter may be a roll of ignited copper gauze or a layer of reduced granular oxide, and should be 5 to 8 inches long. Anterior to this may be, as pro- posed by Professor Johnson, a short layer of copper oxide to oxidize any occluded hydrogen. In the combustion the air is first expelled by liberating car- bon dioxide from a part of the carbonate in the rear ; the ante- rior layers of metallic copper and copper oxide are kept at full red heat ; the substance is burned very slowly, and much time is taken in oxidizing the last of the carbonaceous residue ; and finally the tube is swept out by ignition of the remaining car- bonate in the posterior end. The gases from the tube are re- ceived directly into a Schiif's azotometer, over strong potash solution. In measuring the nitrogen, the room and apparatus being of uniform temperature, a thermometric reading is ob- tained. Estimation' of Oeganic Niteogbn by its Conveesion into Ammonia. The Soda-Lime process of Varentrajij) uml Will. — The nitrogen of nitrates is not included in this estimation. The substance is heated in a combustion-tube in mixture with soda- lime, the products being carried through a layer of red-hot soda-lime of at least half the length of the tube, and received in a solution of acid. The ammonia remaining in the tulje after the combustion is swept out by burning a short layer of oxalic acid in the rear, also by aspiration. If the substance be rich in nitro- gen it is diluted with cane-sugar. Tlie gaseous ammonia from the combustion-tube is received in a known volume of a standard solution of oxalic or sulphuric acid, which is afterward titrated (Peligot's modification) ; or is received in hydrochloric acid for gravimetric estimation with platinic chloride. — Using Peligot's modification. Prof. S. W. Johnson found' that, with various '1879: Am. Ghem. Jour., i, 75; 1872: Am. Chemist, 3, 161. ESTIMA TION OF NITROGEN. 231 substances, under a series of determinations, " tlie soda-iime pro- cess is, to say the least, equal in accuracy with the absolute determination," by volume of free nitrogen. At bright red heat, with soda-lime, ammonia is not decomposed. A cuvihust'ion-tube of 14 to 30 inches (35 to 75 centimeters) length, and near \ inch (10 to 12 millimetens) width, is sealed round at one end (Fig. 23). The Erlenmeyer's gas-furnace is the most convenient. The best bulbed U- tube is that sliown Fig. 23 in the figure. The acid is of about normal strength, titrated with an alkali solution of about half-normal, the latter being exactly valued with a standard acid solution prepared with care. Prof. S. W. Johnson uses standardized hydrocliloric acid and standard solution of ammonia, and titrates with cochineal tincture as an indicator. The same indicator should be used in all titrations ; and if the acid solation Keeoine colored from the combustion, litmus tincture is not applicable. Litmus-papers, blue and red, serve very well. Tlie soda-lime., preferably granulated, otherwise coarsely powdered, is heatetl to remove all moisture, which is strictly excluded imtil the article is used. It may be used warm if the substance is stable enough to suffer no change therefrom. Oxidic acid should be heated on the water-bath to remove all water of crystallization. Asbestos, recently ignited, is required. In the charging of the combustion-tube a layer of about \\ inclies (3 centimeters) of the dried oxalic acid is intro- duced into the rear of the tube, followed by about the same length of soda-lime. The substance under analysis is added from the weighing tube, in quantity about U.5 gram, to some of the soda-lime in a mortar (previously rinsed with the soda-lime), and a mixture made which, with the rinsings of tlie mortar, will fill the tube to a point from two-fifths to one-half its length from the closed end. Or the mixture of the substance with the soda-lime is made in the tube by means of a stirring-wire (Fig. 8), so as to form a layer of near the length just stated. In either case, if the substance be very rich in nitrogen, about an equal quantity of dried cane-sugar may be taken with it in the mixture. The remainder of the tube is filled with the soda-lime to within about 2 inches (5 centimeters) of the rubber sto])per, placing a loosely porous plug of the asbestos, nearly an incii (or 2 centimeters) in length, as a secure guard against the carrying forward of alkaline 232 ELEMENTAR Y ANAL YSIS. dust or spray, and leaving a free space next the stopper. A shield may be put over the end of the tube (Fig. 16). The U-tube is filled and connected as shown in Fig. 23. The more that moisture has been excluded from the soda-lime, the easier will be the combustion. But the use of warm soda- lime in intermixture -with the substance miist not be adopted without assurance that no traces of ammonia are generated in such mixture. If the soda-lime be well granulated, or even coarsely powdered, with tine particles sifted out, it is better not to triturate in making the mixture of the substance, and to do without a channel formed by tapping the horizontal tube on the table, favoring the more intimate contact of empyreumatic gases with the hot soda-lime. But if there are layers of fine powder in the tube, a channel must be provided. In the co'mhustion the layer of unmixed soda-lime is first heated, beginning at the anterior end, and increasing and extend- ing the heat at such a moderate rate that the air-bubbles shall not pass out faster than about two to each second. The heat at the anterior end is so graduated as to prevent condensation of water- vapor in the tube, and not to soften the rubber stopper. When the mixture of substance is reached the layer of clear soda-lime must be at full red heat, and so preserved while tlie flames are advanced backward more gradually than before, delivering only about one bubble every second. The carbonized substance is at last burned out with a full red heat, and when the delivery of gas has nearly or quite ceased the oxalic acid is very gradually heated, so that the carbon dioxide shall not be tumultuously evolved. The carbon dioxide is generated only long enough to sweep out the combustion-tube, when the U-tube may be de- tached. The acid liquid should be as little colored and empy- reumatic as possible. The anterior end of the combustion-tube, in the space in front of the asbestos plug, should not change moistened red litmus-paper. In titrating the acid for the amount of ammonia it has re- ceived, the volumetric alkali is added from the burette directly to the U-tube until the neutral point is very nearly obtained, with litmus-papers or other indicator, not phenol-phthalein. The acid is now transferred to a beaker, with very little rinsing- water, and the titration completed. The value of the alkali solution is found by a volumetric acid of absolute stand- ard. 17 : 14 :: quantity of ammonia : x = quantity of nitrogen. Combustion-tubes with the posterior end drawn out are some- times used, and the residual ammonia obtained by aspiration, or by sending through a current of carbon dioxide. ESTIMATION OF NITROGEN. 233 The gra/ouneirlc deieruLbnutioii of the aininouia, as ammo- nium platinic chloride, is done by the ordinary method, as found in works on inorganic analysis, washing the precipitate with alco- hol or ether- alcohol, and igniting in a weighed crucible. 194.4 parts of Pt i-epresent 14 parts of N. Conihudion with soda-lime in an iron tube may be done with good results,' as the writer has verilied. The tube should be about a third longer, and a little wider, than a glass tube for the same combustion. Special precaution is necessary to avoid burn- ing or melting the stoppers. Combustion with soda-lime, sulphur, and thiosulphate. Euffle's Method, ISSl. Keduction by a powerful deoxidizer in presence of a strong alkali. Obtains the nitrogen of organic, ammoniacal, and nitric combinations. Carried out in the same way as the Varentrapp -Will method in Peligot's modihcation. The method has been well sustained. Dabnky (1885, already cited) found this method, in application to fertilizers containing small amounts of nitrogen, to give results as close as those by Johnson's process for free nitrogen, tlie latter method giving often a little too high, the former a little too low figures for the nitrogen. Greater precautions are required for bodies rich in nitrogen. Details are presented in the Official Methods of the Association of Agricultural Chemists for ISSfl-T, Bulletin No. 12, Department of Agriculture, Washington, 1SS6. Relative determination of the Nitrogen and Carbon. — Applicable when the proportional quantity of nitrogen is not small, or not less than N to 4 C = 14 of nitrogen to 48 of car- bon. The substance is burned, with copper o.xide, and the products passed over hot metallic copper, in a combustion- tube, so as to deliver in a graduated tube the nitrogen and the carbon dioxide. After taking the volume measure of the gases the carbon dioxide is taken up Ity alkali and measurement taken again. Methods of Liebig, Bunsen, and Gottlieb are employed. The determination of carbon, hydrogen, and nitrogen, in one operation, is described by C. (1. Wheeler, 1866 : Am. Jour. Sci., [2], 41, 33. Also by W. IIempel, 1878 : Zeitsch. anal. Chem., 17, 409; Jour. Chem. She., 36, 278. Recently l)y P. Jannisch and V. Meyer, 1886: jBer. d. chem. Gesel., 19, 949 (preliminary notice). 'See also Johnson, 1879: Am. Chem. Jour., i, 82. 234 ELEMENTAR V ANAL YS/S. The dieect estimation of oxygen lias been reported upon aa follows : Baumhauee, 1866 ; Maumene, 1862 ; Mitschbelich, 1867, 1868; Ladenbueg, 1865; Ceetiee, 1874. Estimation of Niteogen by Combustion in the moist way. — The well-known process published by Prof. Wanklyn in 1877 depends on the conversion of the nitrogen of organic compounds into ammonia by the action of permanganate m a very dilute solution of alkaline reaction, the ammonia already contained in the substance being previously distilled off. Its value, in water analysis, is relative rather than absolute, and depends upon its applicability to nitrogenous organic compounds in an extremely dilute solution, so that the changes likely to occur in a concen- tration of the water are avoided. For the analysis of pure ni- trogenous compounds various plans of moist combustion have been proposed of late years. Of these the following method has received general commendation from chemists who have reported trials of it — a method in which oxidation by adding dry perman- ganate to a concentrated acid solution is preceded by the altera- tive action of hot sulpimric acid of full strength : Moist Method of Kjeldahl.' — For bodies moderately rich in nitrogen 0.250 gram is taken ; for bodies with only about 1.5^ of nitrogen 0.7 gram is taken. The substance is placed in a boil- ing-flask of about 100 c.c. capacity, with a long and narrow neck, and of glass capable of resisting the strongest acids. Tiie ilask is placed upon asbestos cloth or copper gauze over a lamp supplying a strong heat, 10 c.c. of pure sulpliuric acid of full strength is added, and digestion instituted (under a hood) at a temperature only a little below tlie boiling point of the sulphuric acid. Sulphurous acid vapors escape. To prevent loss by spirting, the tiask is somewliat inclined during the effervescence. After the liquid comes to rest the digestion is continued (still near the boiling point, as shown by occasional bumping) until the liquid becomes gradually of light color, and finally entirely clear. To ' J. Kjeldahl, Ciirlsberg Laboratory of Copenhagen, 1883 : Zeitsch. anal fS,T-V^v' '^^'^' ^'f^V, ^'''"'' 48' 101; ^™- Chem. Jmir., 5, 456. Freienius, m,4.- Zeitsch amil.Chem.,2z,!.5'i. Czeczetka, 1886: Jfoji«te7t Chem 6 63; Jour. Gliem. Soc. 4S, 688. Wilfaeth, 1885: Chem. Cent, 1885, 17; Jour. Chem. Soc., 48, 837. Bosshard, 1886: Zeitsch. anal. Chcm., 24, 199; Jour. Chem. Soc, 48, 837. C. Arnold, 1886: Arehiv d. Phnrm.. [3], 23, 177 Jour. Chem. Soc 48, 688. Details are defined in the " Official JMethods of tlie Association of Agncultural Chemists," Department of Agriculture, Bulletin No. 13, Washington, 1886. The nse of phenolsulphonic acid is introduced into the process by Jodlbauer, 1886: Chem. Cent., p. 433; Jour. Chem. Soc. 50 ESTIMATION OF NITROGEN. 235 hasten this result a little fuming sulphuric acid or phosphoric anhydride is added. With these additions a digestion of about two hours is usually sufficient. Eut at 100° to 150° C. the for- mation of ammonia is imperfect and the object not attained. The lamp is now removed, and, while the liquid is hot, finely pulverized potassium permanganate is carefully added, either in very small portions or in a very fine stream, which may be car- ried through a delivery-tuliu. The reaction is violent, even ac- companied by small flames, and it is made as gradually as it can be v(rithout interrupting it. When the oxidation is complete a green color appears, and the addition of the permanganate is dis- continued. The li(piid may now be warmed for a few minutes, but not on any account strongly heated. The liquid is cooled, and diluted with water, when the green color changes to brown. When again cool the liquid is introduced into a distillatory apparatus, the generating flask holding about f liter, and con- nected with an upward-sloping top-piece to prevent liquid being carried over l)y spirting, and through the condenser into a re- ceiver containing an accurately measured quantity of acid of known strength. About 40 c.c. of solution of sodium hydrate of sp. gr. 1.30 are (piickly introduced into the distilling flask. [A Welter's safety tube may be provided for this purpose.] And to prevent bumpiirg a little nautallic zinc is introduced, the hydrogen from which secures an even action. The completed distillate is titrated for the ammonia it has received (as in the estimation of Varentrapp and Will). Kjeldahl found his method inapplicable to certain alkaloids, cyanides, volatile acids, and nitrogen oxides. It reduces nitrates in presence of organic matter to ammonia, but incompletely (com- pare Waeixgton, 1^85 : ( 'hem. News, 52, 1G2). Ujxiii the Deferiiiindtioii of Total Nitrtxjeii, organic, am- moniacal, and nitrous, see Eulletin No. 1^, Chemical Division, Department of AoRicuLxrKK, Washington, 1 ssfi, pp. 34, .52. Also, (teemax Manure Manufacturers' Association, 1.SS4: H. II. B. Shepherd, translator. Also, Houzeat, ISS."). Ruf- fle's method to this effect is referred to on p. 233. Bodies coxTAiNrxi; Sui.phub, in ent'Diiiitian of carhon and hydrogen, are subjected to combustion with lead clircjniate in- stead of copper oxide, and the front of the column of lead chro- mate is not heated to full redness. — When chlorine, lromine, or IODINE is present, in combustion to estiouite carbon and hy- drogen, a coil of silver wire is placed in the front of the combus- tion-tube to retain the halogens, which otherwise may interfere 236 ELEMENTARY ANALYSIS. with the result. Chlorine forms cuprous chloride, which will condense in the calcium chloride tube. Copper holds chlorine but imperfectly, and the same is true of lead. The Estimation of Sulphue, in organic analysis of com- pounds not volatile, may be done by fusing with potassium hy- drate and nitrate, in a silver dish, until tlie mass will be white on cooling. The mass is dissolved in water, acidified by nitric acid, and the quantity of sulphuric acid determined by precipita- tion with barium chloride in the manner required in quantitative work. Yolatile compounds can be oxidized with a mixture of sodium carbonate and potassium nitrate in a combustion-tube. Potassium dichromate is also employed as an oxidizing agent in the sarne way. Chloeine, beomine, and iodine are estimated by igniting the substance with an excess of pure quicklime, in a narrow combus- tion-tube. The tube is filled with the lime mixed with the sub- stance, followed by a short column of lime alone, and a channel made by tapping the tube on the table. After the ignition the contents of the tube, when cold, are carefully transferred to a flask containing water, and treated with dilute nitric acid, rinsing tlie tube with the water and then with the acid. The solution is filtered, the residue and filter washed, and the halogens precipi- tated by silver nitrate solution. "With iodine it is better to ex- haust first with water, and add silver nitrate solution to the filtrate, then treat the residue with dilute nitric acid and add the acidulous filtrate to the one containing the silver. By this means the liberation of iodine by action of nitric acid is avoided. The silver precipitate is treated as in ordinary quantitative work for the halogens. Estimation of Sulphue oe of Halogens is effected by the method of Caeius ' From 0.15 to 0.40 gram of the substance is treated with a calculated quantity of nitric acid sufficient to furnish 4 times the required amount of available oxygen, or of acid of sp. gr. from 20 to 60 times the weight of the substance. The digestion is done in a closed tube, sealed, at 120° to 140° C, for some hours. For estimation of chlorine, silver nitrate is added with the nitric acid before digesting. Details may be found in the original papers and'in manuals of quantitative analysis. ' 1860-65: Ann. Chem. Phar., 116, 11; 136, 139; Zeitsch. anal. Ohem., 1 217, 340; 4, 451; 10, 103. DEDUCTION OF CHEMICAL FORMULA. 237 Deduction of Chemical Fokmul.e. — In the first place, the molecular weight of the substance is to be ascertained, if possible. (1) If the compound be sufficiently vaporizable its Vapor Density ' is to be determined and accepted as evidence of the molecular weight. With the weight of air as the unit of gravi- ties, vapor density X 28.86=: molecular weight. With hydrogen as the unit, vapor density X 3 = molecular weight. (2) If the substance have a definite capacity of combining, as a base or an acid, its combining number can l)e detennined by its proportions in formation of salts. If an acid, it is needful to ascertain whether it be monobasic, bibasic, or tribasic in its cajxicities of combination. Certain classes of bases are subject to the corresponding question, whether monacid or not, but the natural nitrogenous bases are mostly monacid. (3) If the substance be found to hold a definite relation to other substances, as shown by its formation, its dceuniposition, or by chemical resemblance to members of homolog(^ns series, its molecular weight may be inferred from such relations. If now m be the molecular weight of a compound ; 7), the percentage of a constituent element ; i\ the combining number of this element ; separate water, and drying, may lie weighed as C^gHggO., . Also the residue of its ethereal solution may be melted, brought to a constant weight, and weighed in the same way. From Oleic acid stearic acid is separated as directed under e, p. 2-1:2; in mixture with Palmitic acid stearic acid is estimated by methods given under Fat Acids, Quantitative Determinations of, (5) and (7), p. 250. g_ — Stearic acid is the " stearin " (if the candle industry. ^ Ding. pol. Joiir., 231, 64; Zeitsch. anal. Clinn.. 18, (122; liciieiiikl's "Analyse der Fette " (1886), p. 81 ; Am. Jour. I'har., 55, :!5i;. 244 FATS AND OILS. For determinations of commercial value see under reference last given, especially methods (4) to (8). Palmitic Acid. — C\uH32*^a = ^56 (monobasic). Margaric Acid.' Found as a normal glyceride in ordinary vegetable and animal fats. a. — As free acid, crystallizable from alcoholic solution in fine needles, sometimes grouped in sheaves, or congealing from a melted mass in partly crystalline forms of pearly lustre. Melts at i\'2° C, at which temperature the li(pud has the sp. gr. 0.8527. At about o50° C. it distils with partial decomposition. It leaves a peruianent oil stain on paper. Under the reduced pressm-e of 100 millimeters it distils at 268.0" C. — The glyceride, Palmitin, G^lrl^{()^Q\l.,^^0.,)Q, is crystallizable, in pearly lustrous forms. It melts at temperatures from 50.5° to 66.5° C, according to its previous exposm'e to heat. Strongly heated it carbonizes abundantly. h. — Palmitic acid, as well as palmitin, is odorless and of a bland, oily taste. c. — Palmitic acid is insoluble in water, and but sparingly and slowly soluble in cold alcohol, requiring 10.7 parts of absolute alcoliol for solution, but hot alcohol dissolves it more freely, yielding crystals as the solution cdids. It dissolves freely in ether. The alcoliolic solution has nu acid reaction. The normal glyceride, palmitin, is but slightly soluble in cold alcoliol, moderately soluble in hot alcohol, and soluble in ether, chloroform, benzene, petroleum benzin, and in carbon disulphide. Alkali palmitates (soaps of palmitin) are s(jluble in water, with tendency to turbidity from slight decomposition, increased by dilution ; more permanently soluble in alcohol, scarcely at all soluble in ether. — Non-alkali metallic palmitates are insoluble in water or ether. Lead palmitate is insoluble in alcdhol. Barium and calcium palmitates are slightly soluble in alcohol. d. — In qualitative reactions palmitic acid does not sensibly difEer from stearic acid. Its distinction from stearic acid re- quires quantitative work. e. — Separations of palmitic acid are made with stearic acid, or, if this be absent, by the same methods given for stearic acid sep- aration (Stearic Acid, e). ' This synonym is used by some French chemists. VARIOUS ACIDS. 245 f. — Quantitative deteruiinatious of palmitic acid alone are done by the metliods given for Stearic acid. When in' mixture with stearic acid, methods of indirect determinatidii are resm-ted to, as given under Fatty Acids, Quantitative Estimation of, (5) and (T). o. — The fourteen-caxhon member of the CnHjnOo series of fat acids. Closely resembles Laurie acid. A solid, melting at .5.'!. 8° ()., at which temperature the liquid has sp. gr. U.8(')32. It is insoluble in water, sparingly soluble in cold alcohol and in ether. Laueic Acid. — The (\.,M.^()„ acid obtained from fats is a solid, fusible at 4s.6° ('., and of sp. gr. O.sSo at '2(»° C. It crys- tallizes from alcohol in needles. It does not vaporize, alone and under ordinary pressure, without being mostly decomposed, but distils with steam. In large quantities of boiling water sensible traces are dissolved. Capeio Acid, ( '10^^20* *2- — "^^^ capric acid obtained from fats is solid at ordinary temperatures, f(jrmiiig small tabular crystals, melting at 31.3° to 31.4° C, boiling at 2(;s°-'J70° C, and of sp. gr. 0.93 at 37" C It is sdluble in about Kmk) parts of water; its calcium salt, very sliglitly soluble in water. Capi;yi.ii; Acid, ('kIIi,;< ).^. — The caprvlic acid obtained from fats cona-eals at 12° ('. to a crvstalline mass, melting at 16.5° C. Boils at ■23r,°-2:',T=' C. At 20° (' has sp. gr. (1.914. Of a sweet taste. Soluble in 400 parts of water. The calcium salt dissolves in 2ftO parts of water. Cai'K'oic Acid, (\Jly.().,. Isohuiyl-ncetic acid. Found as a glvccride in fats.— ('on goals at — ls'° ('., boils at 199.7° (!., is scarcely at all soluble in water. At 20° C, sp.gr. ().02:i. Of a sweetish taste. The calcium salt dissolves in 37 parts of water. Fatty Seeies of Acids, Cnlljn.jOg. Oleic acid series. The following members of this and other "immediately related series are found in fats : 246 FATS AND OILS. Oleic Acid CigHg^Og = C17H33.CO2H. Series CnH2n_203 : Eicinoleic Acid. . . Cj^gHg^Og. Series G,J^in-fi2 '■ Linoleic Acid. . . . CigHogOg = C15H07.CO3H. Oleic Acid, C^^gHg^Og = 282. — The members of the fatty- series CnH2n_202 coiitaiii two atoms of hydrogen less than cor- responding members of the fatty series CnHj^Og , and by action of reducing agents the former are in general convertible into the latter. The normal glyceride of oleic acid, olein, 03115(03^8113302)3 i^ 884, is found in greater or smaller proportion in most vegeta- ble and animal fats, and in non-drying oils. a. — Pure oleic acid is a colorless oil, congealing at 4° C, melt- ing at 14° 0., at wliich temperature tlie liquid has sp. gr. 0.898. Under ordinary pressure it does not distil alone undecomposed, but is carried over with superheated steam at about 250° 0. — The triglyceride, olein, is a liquid which congeals at low atmos- pheric temperatures, and in vacuum distils slowly without de- composition. b. — Oleic acid is a bland, tasteless, when pure nearly or quite odorless liquid, indifferent in physiological action. c. — Oleic acid is insoluble in water, soluble in alcohol not very dilute, and separated from the solid fat acids by its greater solubility in a mixture of acetic acid and alcohol. It is soluble in chloroform, benzol, petroleum benzin, and in the fixed oils. — The triglyceride, olein, is somewhat soluble in absolute alcohol, in fact much more so than are stearin and palmitin, l)ut is inso- luble in dilute alcohol. — Pure oleic acid is neutral to litmus-pa- per, Imt it gives the acid reaction with phenol-phthalein, decolor- ing the alkahne mixture of this indicator at formation of normal alkali oleates. — By exposure to air for a short time oleic acid suffers such changes as impart to it an acid reaction, and it soon becomes rancid and of a yellowish color. — The alkali oleates are soluble in water, the solution becoming somewhat turbid by de- composition when diluted with water, though bearing dilution better than stearate or palmitate. The oleates of non-alkali me- tals are insoluble in water, but more or less freely soluble in al- cohol, and in some instances (including the lead salt) soluble in OLEIC ACID. 247 ether. The silver oleate is not soluble in ether. — The alkali oleates are precipitated from their aqueous solutions by sodium chloride, and to some extent by excess of alkalies. Sodium oleate is soluble in 10 parts of water at 12° C, in 20.6 parts of alcohol of 0.S21 applied at 13° C, or in 100 parts of boiling ether. From absolute alcohol it is crystallizable. Potassium oleate, in ordi- nary moist condition, is soft or gelatinous, and is much more so- luble in water or alcohol or ether than is the sodium salt. Ba- rium oleate is insoluble in water, and but very sligiitly soluble in alcohol. Magnesium-alkali oleate possesses a capacity of slight and transient foaming in aqueous solution, perhaps due to a tardy precipitation, and distinguishing it from calcium oleate in the soap test of hard waters. (?. — Oleic acid is characterized by its consistence as a liquid non-volatile fatty body, and by the action of oxidizing agents upon it. Nitric ajcid with metallic copper, fuming nitric acid, mercury nitrates, or other form of nitrous acid, in digestion with oleic acid, j)roduees its isomer elaidic acid, as in digestion with olein it forms elaidin, glyceride of elaidic acid. Elaidic acid is a solid, and its formation is indicated first In- a soft waxy, and finally by a resinous e( insistence. Elaidiu acid dissolves in alco- hol, from which it ci-ystaJlizes in tabular forms, melting at 45° C. — Bromine acts readily, and iodine or chlorine quite easily, on oleic acid, producing dibmin-stearic acid, an addition product of oleic acid, Cj-IT33Br2.('(),,II, on the type of the f'nllznOo series. To 7 parts of the oleic ai'id 4 parts of bromine are added, drop by drop, stirring after each addition. The product is yellowish, of an oily consistence. To form the di-iod-stearic acid, molecular proportions of the oleic acid and of the iodine are taken, each being dissolved in alcoliol, when the iodine solution is gradually added, this being the reaction of Hiibl's estimation, giving the iodine number. g. — S/>j>iir(itioi)s. — Tn manufacture oleic acid is separated from the solid fat acids by filtration under pressure at low tempera- tures above the congealing point of the oleic acid. For methods of separation from the solid fat acids by sol- vents, etc., see Stearic acid, e. Directions for separation (pro- duction) from olein by saponification are essentially those given under Hehner's method. f.—Qtiantitatlve.— Oleic, acid is estimated volumetrically by standard solution of potnssa or soda, using phenol-phthalein as an indicator. Each c.c. of normal solution of alkali represents 248 FATS AND OILS. 0.282 gram of oleic acid. Taking 2.82 grams of material, each c.c. of deciiiormal solution of alkali counts 1 per cent, of oleic acid. Taking 14.1 gram of material, c.c. of normal solution of alkali X 2 ^ jjer cent, oleic acid. Gravimetric estimation of free oleic acid is eiiected by adding to the free acid, in a la3'er over an aqueous liquid, a weighed portion of recently fused beeswax or paraffin, heating to melt the solid, and when cold detaching the oily mass, drying in a tared capsule, ,and weigliing, when the weight of the wax is subtracted. Also free oleic acid, dissolved in ether, may be freed from the latter by evaporation in a tared beaker or flask, avoiding oxidation by exposure to the air, and tlie weight of the oleic acid may be obtained. g. — The U. S. Ph. gives the following specifications for oleic acid: "At 14° C. (57° F.) it becomes semi-solid, and remains so until cooled to 4° C. (39° F.), at which temperature it becomes a whitish mass of crystals. At a gentle heat the acid is completely saponified by carbonate of potassium. If the resulting soap be dissolved in water and exactly neutrahzed with acetic acid, the liquid will form a wiiite precipitate with test solution of acetate of lead. This precipitate, after being twice washed with boiling water [drained and dried], should be almost entirely soluble in ether (absence of more than traces of palmitic and stearic acids). Equal volumes of the acid and alcohol, heated to 26° C. (77° F.), shouhl give a clear solution, without separating oily drops upon the surface (fixed oils)." — The specifications of the Br. Ph. are as follows : " A straw-colored liquid, nearly odoiless and tasteless, and witli not more than a very faint acid reaction. Unduly ex- posed to air it becomes brown and decidedly acid. Specific gravity O.SOO to O.Sitl.t. At 40° to 41° F. (4.5° to 5.0° C.) it be- comes semi-solid, melting again at 56° to 60° F. (13.3° to 15.5° C.) It should be completely saponified when warmed with carbonate of potassium, and an aqueous solution of this salt neutralized by acetic acid and treated with acetate of lead should yield a preci- pitate which, after washing with boiling water, is almost entirely soluble in ether." KiomoLEic Acid, C-l8II3403=298. — The fat acid constituting, in its normal glyceride, the principal part of castor oil In com- position an oxy-oleic acid of the proportions CnH2n-203- a. — A thick oil, of sp. gr. 0.940 at 15° C, congealing at— 6° to —10° C, and does not vaporize undecomposed. The lead salt melts at 100° C. b. — The glyceride, as obtained in castor oil, is odoidess, with a LIN OLEIC ACID.— HYPOGAIC ACID. 249. mild taste and slightly acrid after-taste, aud exerting a cathartic effect. c. — Ricinoleic acid is insoluble in water; sohihle in all pro- portions in alcohol aud in ether. The lead salt is soluble in ether. Castor oil is soluble, at 15° C, in 2 parts of Wi alcoliol or ■± parts of S-ifo alcohol. It is Ijut slightly soluble in petroleum benzin, paratHn oil, or kerosene, though it takes up about its own volume of petroleum benzin. d. — Ricinoleic acid is but very slightly oxidized by exposure to air. Treated with bromine it takes two atoms of bromine in the molecule of the acid, forming V^^^^xjd.^, corresponding to the reaction of oleic acid. In the elaidin reaction, by action of nitric acid, ricinelaidic acid is formed, isomeric with ricinoleic acid, and fusible at 50° C. LiNOLEic Acid, C;LgHo80o=:252. — The only well-known mem- ber of the series of fat acids OnH2„_402. In the normal glyce- ride forms the principal portion of linseed oil, representative of the drying oils. In oxidation, or " drying," it forms addition products, such as f\6'^T28-'^''4^3' corresponding in composition to CnH2nOo. Therefore in reaction with oxidizing agents it has twice the saturating power per molecule possessed by oleic acid. (Z.^Linoleic acid is a permanent liquid of a pale yellow color and sp. gr. O.'.tifOG at 1-1° C. The glyceride, as obtained in linseed oil, congeals at —16° (/. (Gussbbow), —27° C. (Aechbutt and Al- len), and melts at 16° to ^0° C. (Glassnee). h. — Linseed oil has a characteristic odor and taste. <;. — Insoluble in water, readily soluble in alcohol and in ether. Of u feeble acid reaction, and capalilc of neutralizing alkalies to phenol-phthalein and other indicators. The barium and calcium salts dissolve in hot alcohol. Ether dissolves the linoleates of lead, zinc, co}>per, and calcium. (l_ — Linoleic acid is easily oxidized by exposure to the air. In thin layers in a few days it forms a solid, resin-like body known as Oxylinoleic acid, and afterward takes on tlic character of a neutral ' body, insoluble in ether, and sometimes termed Linoxyn. Hypogaic Acid, Gj„II.,oO^.— A white solid, crystaUizing in needles, melting at P>3" C, not readily vaporizing in ordinary conditions without decomposition. By exposure to air soon be- 2SO FATS AND OILS. comes rancid, acquiring a brown color, and giving origin to vola- tile acids. In the elaidin test it is changed to its isomer gaidic acid, fusible at 39° C. Phtsetoleic Acid, isomeric with Hypogaic acid, C^gHgoOg , melts at 30° C, and is not affected by the elaidin test. Fat Acids, Quantitative Deteeminations of. — Besides the methods of volumetric and gravimetric estimation of separate fat acids, 01' of total fat acids in terms of stearic acid, by equivalence of saturation, certain special determitMtions have been made, upon stated authorities, as indices of composition, related to as- certained limits, representing values for given uses. (1) The number of parts of insoluble fat acids obtainable from 100 parts of clear neutral fat (IIehnee's number). (2) The number of c.c. of decinormal alkali solution saturated by the volatile fat acids distilled from 2.5 grams of the fat (Reicheet's number). (3) The number of milligrams (thousandths) of potassium hydrate saturated by saponifying 1 gram (one part) of the fat (Kottstoefee's number). The saponification number. The methods above named have been devised to distinguish butter from its substitutes. (4) The percentage of iodine which the oleins of the fat will take into combination by a defined procedure (Hubl's iodine number\ (5) The molecular weight, as obtained hy acidimetry. (The quantity saturated by lOOO c.c. normal solution of alkali.) For mixtures of palmitic and stearic acids. (6) The specific gravity, as a limited indication. (7) The melting and congealing points. (8) Calculation of constituent Fat Acids and Neutral Fats. (1) Estimation, of the insoluble fat acids : Hehnee's Method.' — To obtain the butter fat from butter melt a portion on the water-bath, leave the liquid to settle while melted, decant the clear liquid only upon a dried filter in a hot funnel, and take the filtrate. It must be perfectly clear and not lose weight on '0. Hehnee, 1877: Zeitsch. anal. Chem., i6, 145. Hehner and Angell, 1877: "Butter, its Analysis and Adulterations," London, second edition. Mu- ter, 1876: Analyst, i, 7. Dupre, 1876: Phar. Jour. Trans.. [3], 7, 131. Jones, 1877: Analy.1t. 2, 20. Pleischmann and Vieth. 1878: Zeitsch. anal. Chem., 17, 287. Manipulation at the Depart, of Agriculture, Washington, Report Deft. Agr., 1884, Prof. Wiley, Chemist, p. 60. Further, see citations under Butter Fat. DE TERM IN A TION OF FAT A CIDS. 2 5 1 the water-bath. Keep in a Hght beaker, and take out for an analysis from 3 to 4 grams of the clear fat into an evaporating- disli of about 5 inches (13 centimeters) diameter, using a glass rod to be left in the evaporatiiig-disli, and weighing tl>e lieuker before and after the removal to obtain the exact weight of fat taken. Add 50 c.c. of alcohol of about 85^, and 1 to 2 grams of pure (alcoholic) potassium hydrate, and warm and stir the mix- ture until a cKnu- solution is obtained. After five minutes' fur- ther warm digestion add a few drops of distilled water, and if a turbidity is caused continue the digestion until the addition of water produces no turbidity. If this satisfactory saponification is not attained the failure is probably due to a too great dilution of the potash with alcohol, and the operation is to be commenced anew. If the alcohol be too strong, saponification is prevented. The clear saponified solution is now evaporated over the water- bath to a syrupy consistence, and the residue dissolved in lOO to loO c.c. of water. To the clear liquid add diluted sulphuric or hydrochloric acid to a strongly acid reaction. The creamy sepa- rate of the insoluble fat acids rises foi- the most part to the sur- face. Heat of a bath of water below boiling is now applied to melt the precipitate, and continued for half an hour and until the layer uf fat acids above is perfectly clear and the aqueous liquid below is nearly clear. Meantime a filter of -i to .5 inches (10 to 13 centimeters) diameter, of the closest filter-paper (Swe- dish), is dried in the water-box. The filter should be close enough to transmit hot water only by drops. A small beaker is weighed, als(.) a filter weighing-tube and this tube with the filter, to give the weight of the latter. The weighed filter is placed in a funnel wetted and half-filled with water. The water}- liquid and melted fat are then poured from the dish upon the filter, which is not to be at any time more than two- thirds filled ; the dish and rod are rinsed with boiling water, and washing with boiling water is to be continued until the washings cease to redden litmus-paper, about f liter (TOO to 1()(H) c.c.) of filtrate being usually obtained.' (The rins- ing of the dish seldom leaves behind more tlian a milligram of fat, but this is saved by taking it up with a little ether and the solution added to the fat acids in the beaker afterward.) The ' Fleisciimann and Vieth (IHTH) advise care to avoid iinperrect solution of lauric acid (abounding in eocinimit, oil), washing until 5 c.c. of (lie filtrate ceases to change the color of 0110 drop of litmus tincture added thereto. E. Wallbb and his associates (18K(;: Report N". Y. State Dairy Commissioner) wash with si.\ or seven inslalirients of hot water (al)out 100 c.c. each), rinsing oflE between each with about 2r) c.c. of cold water. 252 FATS AND OILS. drained funnel is set well down in a beaker of cold water, and when the fat acids have hardened the filter is detached, drained, and placed in the weighed beaker.' This is heated on the water- bath to a (nearly) constant weight. Weigh after about two hours' drying, and after a half-hour's further drying weigh again. If any drops of water collect below the fat add a drop or two of alcohol. In this drying there may be slight increase by oxida- tion of oleic acid, and slight decrease by vaporization of fat acids. If the filter have been close enough no fat globules will have passed, and none will be revealed by microscopic examination of the filtrate. The weight of the beaker and contents, minus the weights or tares of the beaker and the filter, leaves the weight of the fat acids, which is to be divided by the weight of purified fat taken,, to obtain the proportion ( X 100 = ^ ) of insoluble fat acids. If 87.5 be accepted as the full per cent, of insoluble fat acids in butter, and 95.5 as the per cent, of insoluble fat acids in " meat fats," then 95 5 — 87.5^8, and 8 : found percentage minus 87.5 :: 100 : « = per cent, of " meat fats" present in the clear fat examined. For the calculation of percentage in entire but- ter see under Bntter, Interpretation of Results. Dalican modifies ITehner's process by taking 10 grams of the clear bntter fat in a flask of 250 to 300 c.c. capacity, and adding 80 c.c. of 85;^ alcohol, and 6 grams of sodium hydrate dissolved in 6 to 8 c.c. water, when by 30 to 40 minutes of warming and stirring the saponification is ended. The alcohol is evaporated off, 150 c.c. of water added, and 25 c.c. of hydrochloric acid diluted with four parts of water are added in small portions at a time, rotating the flask after each addition. The mixture is now heated over the water-bath for 25 to 30 minutes, until the fat layer separates with perfect clearness and white points are no longer seen. The flask is set aside for 30 minutes, and then cooled with water. After two hours the fat layer is broken with a glass rod, the water poured on a wetted filter, about 250 c.c. of boiling water added in two portions to the flask, shaking after adding the first portion. The flask is then set aside 40 minutes, cooled by immersion in water, and the water decanted on the filter as before. This washing by decantation, as above^ is repeated until the decanted liquid ceases to redden litmus- paper on 20 minutes' contact, 8 or 10 washings being necessary. • "The insoluble acids are brought into a tared dish, any in the filter or flask being dissolved in ether, dried at 100° C. with stirring with ahsnlnle alco- hol to remove water, and weighed." H, W. Wiley, Chemist Dept. Agricul- ture, Washington, Report of 1884. DE TERMTNA TION OF FAT A CIDS. 253 The insolubk' fat acids are finally c;athered in a tared jmrcelain I'apsule or evapoi'ating-dish, the flask being washed with hot water, and all washings passL-d through the filter. The filter iimst he kept wet, and the slight portiim of fat acids npim it can easily be detaclicd. The drying is done at 1U()° to liU° CJ., at first for an hour, and a second weight is taken in 15 or iiO minutes. For results with vegetable and aninuil fats see tables following ; also Butter Fat. (2) Rk.U'Ukkt's iHiiJiixP embraces the estimation of the vola- tile fat acids, separated liy distillation. " Ueichert's number" is the number of c c. of deeinormal solution of alkali taken to neu- tralize the distilled fat acids from 'J. 5 grams of fat. Sometimes, however, results are sjiecified for 5 grams or for 10 grams of the fat. i)X the ch-ar fi'tcred fat :3..") grams are taken in an Erlen- meyer's flask of about 150 c,c. capacity, with 1 gram potassium hydrate and 20 c.c. of SOv' alcohol, and the wlicjle digesten-Equ-i- valeiit " of fats. The latter term is defined as the number of milligrams of fat saponifiable by 1 c.c. of normal alkali solution. For tlie triglycerides it is the third of their molecular weight ; or it is the liydrogen-equivalent number of the fat. 56000 ~ Kottstorfer's number =" saturation-equivalent " ; and 56000 -e- " saturation equivalent " = Kottstorfer's number. Perkins ' combines the methods of Hehner, Reichert, and Kottstorfer, as follows : Of the clear fat 1 to 2 grams is saponified ; an excess of a cold-saturated solution of oxalic acid is added, and tlie fat acids separated in the cold, and then washed on the filter with liot water. The filtrate is made up to 200 c.c, and distilled ' F. P. Perkins, 1878: Analyst, 3, 241; Zeitsch. anal. Chem., 19, 237. 256 FATS AND OILS. to give 100 c.e. of distillate (according to Eeichert), this being titrated with alkali and the result stated in milligrams of potas- sium hydroxide to saturate the volatile acids from 1 gram of pu- rified fat. The insoluble fat acids, as washed, are dissolved in loo c.c. of hot alcohol, and this solution, or an aliquot part of it, titrated with decinonual alkali, calculating the result into milli- grams of potassium hydroxide for the insoluble fat acids of 1 gram of fat. The former number plus the latter number gives the milligrams of potassium hydroxide to saturate all the fat acids of the 1 gram of purified fat. Percentages of Insoluble Fat Acids. Hehner's Wumhers. Olein 95.75 Theoretical quantity. Palmitin 95.28 " " Stearin 95.73 " " ]'>uryriH 87.41 " " Oleomargarin 95.56 Hehnee's determinations. r^ ii J -i ( 95.75 (Bensemann). Cotton-seed oil | 9^29 (E. Wallek, 1886). Cotton stearin 95.5 (MuteeV Lard 96.15 (West-Knights). r^v ■^ \ 95.43 ^^l'^««^^ 195.09 (E.Wallee). Peanut oil 95.00 Palm oil 95.6 (Hehnee). Sesame oil 95.48 (E. Waller). Tlieobroma oil 94.59 (Bensemann). Seal oil 90,68 (E. Waller). Kape oil 95.10 (Bensemann). ^ , ., ( 86.43 (Mooee). CoCOanut oil { on na )t? TTT \ ( 80.78 (E. Wallee). Butter fat, lowest 86.6 (Hehnee and Angell). " highest 88.5 " " " common maxi- mum 87.5 " " Butter fat, lowest of nine. . . " liighest " ... From 26 genuine j lowest. American butters, j liighest From 25 butters, ) lowest. Pennsylvania . . . . ( highest 88.50 89 S9 86.40 90.24 86.7 87.7 Wiley, Washington, 1884. E. Waller, New York, 1886. C. B. Cochran, 1886. DETERMINATION OF FAT ACIDS. 257 Saponification Coefficients : Kottstorfer' s Naribbers {^jp.lh^t). (Milligrams of KOIl neutralized in saponifying^ 1 gram of Fat.) Stearin 1S8.8 By calculation. Olein 190.0 " Palmitin 208.0 " Butyrin 557.3 •' Beef Tallow 196.5 Kottstokfek. " " commercial. . . . 196.8 " Mutton Tallow 197.0 " Lard 195.7 " Olive oil 191.8 " Kape " 178.7 " ( mean. . . 227.0 " Butter Fat \ lowest. . 221.5 " ( highest. 233.0 " Fat of Rancid Butter — about 1.5 lower than when fresh. " Cocoanut oil 250.3 (Mooee, 1884). " " washed 246.2 " " " 49.3^, Oleomar- garin mn< 220.0 " Cocoanut oil 70.2^, Oleomar- garin 29.S;^ 234.9 " Aknond oil, sweet 194.7-196.1 (Valenta, 1883). Apricot oil 192.9 Bitter Almond, fixed oil.. 194.5 ( 181.0 Castor oil | 176-178 (Allen, 1884). Cotton-seed oil 195 (Valenta). Lard oil 191-196 (Allen). i 189-195 " 195.2 (Mooee). 191.7 (Valenta). 191-196 (Allen). 185.2 (Mooee). „ , ., j 191.3 (Valenta). Peanut oil | ^gg g (Mooee). Sesame oil 190. (i (Valenta). Sperm oil 130.O-134.4 (Allen). Theobroma oil 199. S (Mooee). Train oil 190-191 (Allen). Messrs. Wallek an(J Maetin (1886 : Eeport of the Dairy 258 FATS AND OILS. Commissioner of tlie State of New York) obtained, from 25 genu- ine American butters, Kottstorfer's numbers from 220.6 to 230.1 (extremes) ; a rancid butter, 223.0 ; the same deodorized, 219.45 ; and from the insoluble fat acids of a butter, 214.25. From oleo- margarin 188.65; another, 191.6. From mutton suet, 203.25; beef suet, 199.2; lard, 195.85. From cottonseed oil, 162.0 to 193.05 ; average of five, 183.47. (4) Determination of Fat Acids hy their capacity of combi- nation with iodine. — The fat acids, whether free or in their glycerides, form combinations with iodine, bromine, or chlorine. One molecule of oleic acid or ricinoleic acid takes two atoms of iodine ; one molecule of linoleic acid, four atoms of iodine ; ad- dition products being formed. The directions of HiJBL ' for finding the percentage of iodine taken into combination (the iodine number) are as follows, com- mencing with preparation of the needful reagents : (1) Iodine solution. Of iodine 25 grams are dissolved in 500 c.c. of alcohol (free from fusel oil); of mercuric chloride 30 grams are dissolved in 500 c.c. of the alcohol, and this solution filtered if necessary; when the two solutions are united, and, after 6 to 12 hours' standing, titrated with the standardized thiosulphate solution, and the standard noted. — (2) Thioszdphate sohition. A solution of about 24 grams of sodium thiosulphate in the liter is made, and its iodine value accurately detei-mined with a weighed quan- tity of freshly sublimed iodine. About 0.2 gram of resublimed iodine is placed in a small glass tube closed at one end and pro- vided witli a similar tube enough larger to serve as a cover, both tubes being previously dried and weighed. The iodine is heated in the inner tube, on a sand-bath, until it melts, then covered with the outer tube, cooled in a desiccator, and weighed. The cover is now removed and both tubes are placed in a stoppered flask con- taining 1 gram of potassium iodide (neutral and free from iodine) dissolved in 10 c.c. of water. When the iodine has dissolved, the solution of thiosulphate of sodium is added from a burette until the iodine color is reduced to a faint yellow, a little starch solu- tion is added, and the titration completed to the extinction of the blue color. The iodine value of the thiosulphate solution is now written. — (3) Chloroform. The purity of chloroform is as- sured for this assay by digesting 10 c.c. of it with 10 c.c. of the iodine solution at ordinary temperature for two or three hours' and titrating to the extinction of the iodine with the thiosul- '1884: Ding. pol. Jour., 2S3, 281; Jour. Chem. Soc, ^6, 1435; Am. Ghem. Jour., 6, 285. DETERMINA TION OF FAT ACIDS. 259 phate solution, tlie stated (niautity of which should be consumed. — (-i) Potassiain lodiear-shaped with a very 266 FA TS AND OILS. tapering end. The bulb should displace as nearly as possible 1 c. c. of water, and should be so weighted by the introduction of mercury as to weigh 3.4 grams. Differences of 0.005 to 0.01 weight have little eifect on the results. The following directions for taking " the sinking point " of butter will indicate the method of application to any fat. Of the butter 20 to 30 grams are melted in a beaker over the water-bath, then poured into a test-tube f inch wide and 6 inches long, filling to within two inches of the top. The tube is kept warm until the fat is clarified by the settling of the water, curd, and salt, when the fat is solidified at 15° C. by immersing the tube in water of this temperature. (The cone of depression on the top of the fat serves to indicate its relative fusing point. Pure butter fat shows only a slight depression, while admixtures with fats of high melting points show a considerable hollow cone.) The tube is now placed in about one liter of cold water, in a beaker, the test-tube being se- cured so that the top of the fat is about 1-J inches below the sur- face of the water. Heat is now applied to the beaker by a sand- bath or by asbestos felt, over a lamp. The surface of the fat is made level, and the weighted bulb placed thereon. The water is stirred from time to time. A thermometer is placed in the water, with the bulb near the surface of the fat, and the temperature read off just as the globiilar part of the bulb has sunk beneath the fat. Hehner and Angell found *he average sinking point of the fat of 21 genuine butters to be 35.5° C. (96° F.), with extremes of 34.3° to 36.3° C. (93.7°-97.3° F.) Of the fatty acids of but- ter fat, 40.5° to 42.1° C. Of beef tallow, average, 50.6° C. (48.3° to 53.0° C); of mutton tallow, 50.9° C. average (50.1° to 51.6° C.) ; of lard, 41.1° to 45.3° C. ; of stearin, 62. 8° C. ; of cacao but- ter, 34.9° C. ; of palm oil, 39.2° C. To calculate the mean sinking point of a mixture of two fats of known composition, having their respective sinking points (S^ and Sg), and percentages in the mixture (F;^ and Fg) : I 1 A li ~r V 2 21 _ sinking point of the mixture. Results ''l + -*^2 of admixture are compared with calculated averages, as follows : 66.7'?; butter and 33.3^ tallow, 43.1° C. found, 42.08° C. calculated. 73.0 " 27.0 " 42.3 " ' 40.2 lO.o " 90.0 " 48.8 " 49.6 " 85.0 " 15.0 " 38.1 " 38.1 " Hassall use's a light bulb, weighing 0.18 gram, and of the -volume of about 0.5 c.c, sunken in the solidified fat in a test- DETERMINA TION OF FA T ACIDS. 267 tube \ inch wide and 4 inches high. " The rhing point " is taken at the temperature when the bulb rises, during the gradual application of lieat, by the softening of the fat. Ilassall also re- cords '•'•llxQ point of clearoiice" when the fat becomes clear, this point being usually 1° or '1° C. above the rising point. The coiiyealiiuj point is more often inconstant than the melt- ing point. It is sometimes taken as the point of commencing turbidity in a mass of melted fat, and sometimes as the point of formation of a coherent solid. Dalican made determination of the congealing point by use of a test-glass 10 or 12 centimeters (1 or 5 inches) long and 1.5 or 2 centimeters (0.4 or 0.6 inch) wide. The tube is two-thirds tilled with the fat, warmed, and the fat stirred with a glass rod, to liquefy the contents. A ther- mometer, graduated in fifths, is suspended in the fat, loosely ad- justed by a perforated cork at the month of the tube, the bulb resting in the centre of the fat. When crystallization commences on the edge the mass is stirred with the bull) of the thermometer, by which the temperature is caused to fall a little, after which it soon rises to near the point before noted, and when it stands constant for two minutes the temperature is taken as the con- gealing point. Some fats, in congealing, show a rise of tem- perature after the solidification has fairly set in, and the maximum of this rise is sometimes taken as the congealing point (see the table at p. 271). Melting and Congealing Points of mixtures of Stearic and Palmitic acids (Heintz) : Stearic acid. Palmitic acid. Melting -point. Congealing point. 100^ Ofo 69.2° C. — .-° c. 90 10 67.2 62.5 80 20 65.3 60.3 70 30 62.9 59.3 60 40 60.3 56.5 50 50 56.6 55 40 60 56.3 54.5 32.5 67.5 55.2 54 30 70 55.1 54 20 80 57.5 53.8 10 90 60.1 54.5 100 62.0 268 FA TS AND OILS. Congealing Point of mixtures of Solid fat acids ("Stearic acid") and Liquid fat acid (" Oleic acid") as obtained from Tallow (Dalican, 1880) : Congealing point. °C. "Stearic acid" in 100 parts of Tallow. " Oleic acid" ill Ida parts of Tallow. 35° 35.5 25.20 parts. 26.40 69.80 parts. 68.60 36 27.30 67.70 36.5 28.75 66.25 37 29.80 65.20 37.5 30.60 64.40 38 31.25 63.75 38.5 32.15 62.85 39 33.45 61.55 39.5 34.20 60.80 4:0 35.15 59.85 40.5 36.10 58.90 41 38.00 57.00 41.5 38.95 56.05 42 39.90 55.10 42.5 42.75 52.27 43 43.70 51.30 43.5 44.65 50.35 44 47.50 47.50 44.5 49.40 45.60 45 51.30 43.70 45.5 52.25 42.75 46 63.20 41.80 46.5 55.10 39.90 47 57.95 37.05 47.5 58.90 36.10 48 61.75 33.25 48.5 66.50 28.50 49 71.25 23.75 49.5 72.20 22.80 50 75.05 19.95 50.5 77.10 17.90 51 79.50 15.50 51.5 81.90 13.10 52 84.00 11.00 52.5 88.30 6.70 53 92.10 2.90 DE TERMINA TION OF FAT A CIDS. 269 Melting and Congealing Points of the Acids of Solid Fats (liiJBL). Fat acids of Melting. Congealing. Oleoinargarin Palm oil 42.0° C. 47.8 45.0 41.8 52.0 42.5 38.0 24.6 39.8° C. 42 7 Tallow 43 "Wool fat , . .. 40 Cacao butter 51 Mace oil (nutmeg oil) Butter fat Cocoanut oil 40.0 35.8 20 4 Melting and Congealing Points of the Fat Acids of Oils (Bach). Fat acids of Melting. Congealing. Olive oil 26.5-28.5° C. 38.0 35.0 33.0 23.0 20.7 13.0 Not under 22° C Cdttiju-seed oil 35.0 Sc^ainu oil 32.5 Peanut oil 31.0 Sunflower-seed oil 17.0 Rape oil 15.0 Castor oil 2.0 270 FATS AND OILS. Congealing Point of mixtures of certain proportions of com- mercial Stearic acid of stated melting points, as obtained from, Tallow (Scheppeb and Geitel, 1882). Congealing point of the tallow -fat The tallow-fat icids containing in per cent, of of congealing point of ' 'Stearic acid " acids. 1 48° C. 50° C. 53° 0. 54.8° C. 10° C. 3.2 2.7 2.3 2.1 15° 7.5 &.& 5.7 4.8 20° 13.0 11.4 9.7 8.2 25° 19.2 17.0 14.8 12.6 30° 27.9 23.2 21.4 18.3 35° 39.5 34.5 30.2 25.8 36° 42.5 36.9 32.5 27.6 37° 46.0 40.0 34.9 29.6 38° 49.5 42.6 37.5 32.0 39° 53.2 45 8 40.3 34.3 40° 57.8 49.6 43.5 37.0 41° 62.2 53.5 47.0 40.0 42° 66.6 57.6 50.5 42.9 43° 71.8 62.0 54.0 46.0 44° 77.0 66.2 58.4 49.8 45° 81.8 71.0 62.6 53.0 46° 87.5 75.8 67.0 56.8 47° 93.3 80.9 71.5 60.8 48° 100.0 87.2 76.6 65.0 49° 93.0 81.7 69.5 50° 100.0 87.0 74.5 51° 93.5 79.8 52° 100.0 84.8 53° .... 90.1 54° .... .... 95.3 54.8° 100.0 Congealing Points of Oils (Municipal Laboeatoet of Paris). Olive oil. Cod-liver Kape oil. . . Colza oil . . Peanut oil.. Almond oil oil. + 2°C. - 3.75 - 6.25 - 7 -10 Beechnut oil -17.5° C. Cameline oil — 18 Poppy oil —18 Linseed oil —27.5 Hempseed oil —27.5 BE TERM IN A TION OF FA T ACIDS. 271 Melting and Congealing Points of Solid Fats, Wimmel (1868). Tallow, beef, fresh. . . . " " old " sheep, fresh.. . " " old. . . . Lard Butter fat, fresh Firkin butter Japan wax Cacao butter Cocoanut oil Palm oil, fresh, soft. . " " hard . " old Mace oil (nutmeg oil). Beeswax, yellow Spermaceti Melting point In congealing he- come turhid at In congealing, temp, rises to 62-62.5 44-44.5 36-37° C. 38 40^1 44-45 32 19.5-20.5 25.5 45.5^6 27-29.5 22-L'3 21.5 35 39.5 41.5-42 below the melt^ without devel- warmth. Other Authorities : Cholesterin 145- 137- 58- 50 79 85 -146 -138 84 Isocholesterin Ceresin (ozokerite). . . . Cetyl alcohol Ceryl alcohol Myricyl alcohol 272 FA TS AND OILS. Steaein Percentage in Oleomaegaein, accoeding to Congeal- ing Points.' Per cent, of Per cent, of Per cent, of Congealing Stearic ac. Congealing Stearic ac. Congealing Stearic ac. at °C. ofAS'O.'' at °C. of 48° C. at°C. of 4.8° C. 5.4° 20° 12.1 35° 39.5 6 0.3 21 13.2 36 43.0 7 0.8 22 14.5 37 46.9 8 1.2 23 15.7 38 50.5 9 1.7 24 17.0 39 54.5 10 2.5 25 18.5 40 58.9 11 3.2 26 20.0 41 63 6 12 3.8 27 21.7 42 68.5 13 4.7 28 23.3 43 73.5 li 5.6 29 25.2 44 78.9 15 6.6 30 27.2 45 83.5 16 7.7 31 29.2 46 89.0 17 8.-8 32 31.5 47 94.1 IS 9.8 33 33.8 48 100.0 19 11.1 34 36.6 EiJDOEFP (1872). Melting point. Congealing point. In congealing, tem- perature rises to Yellow wax. . . . 63.4 61.5, 62.6, 62.3 Wliite wax .... 61.8 61.6 Paraffin 49.6 49.6 a 52.5, 54.0 53.0 a 53.0 52.9 a 52.7, 53.2 52.7 Spermaceti 43.5 43.4 '• 44.1, 44.3 44.2 Stearic acid, ( 55.3 55.2 \ 56.2, 56.6 55.8 commercial 56.0, 56.4 55.7 Japan wax 50.4, 51.0 50.8 r'acao butter. . . 33.5 27.3 M:\ve oil (nut- meg) 70, 80 • . . • 41.7, 41.8 Tallow, sheep. . 46.5, 47.4 32, 36 j a few de- ( grees. u a 43.5, 45.0 27, 35 ' Benedikt's "Analyse der Pette,"p. 131. - Congealing point. DE TERMINA TION OF FAT A CIDS. 273 (8) Calctdation of the cdiistitnrnt Juit Ac.'nh and Neutral Fats, and (lie ra/ue fur 2)r to O.'.KM); vaselin (lil at ^:)(»°-;_!5() ' (1, and of sp. t;r. U.9()0 to ().'.i:!0.~The Tar ( )i]s distilled from eoal-tar as " dead oils," from ^40^0. to .'!5u"' (J./ purified by so(hi l^'e, are used as lubricating oils, and have sp. gr. above 1, indeed above l.olO. As to Uosiu Oils, see page l^SO. Of thr. nolJilx, Paraffins are white, odorless, of sp. gr. u.Stli* to 0.943, distil without diange, are graded by congealing jioints .'>S° to S2" ('., and dissolve in alcohol. Ceresin or Ozokerite is not distilletl, is puriiied by sul- phuric acid, and agrees in general with paraffin in specilic grar- vities and congealing jxiints. In the elaisin Oils, — For the solid non-saponifiable matters the melting ])oints are observed (see Melting and Congealing Points of Solid Fats, p. 271). Treated with an equal weight of anhydrous glacial acetic acid, boiling some time with a return-condenser, tlie fat alcohols (cetyl alcohol, etc.) dissolve completely, cholesterin (•rvstallizes on C(n)liug, and ])ara,ffins or ceresins swim undis- solveil while liot and congeal on cooling. \(iii xdpoiiiliiiJiJi' iimttevK (Injd rdctirhmia or oilier hodicK) in {he FiitK utiil WiiMs. (Allen and TH0Mrs(j.\, 18sl.) — P>y sapo- nification and extraction witli petroleum benzin there were found (d' unsa|)oiiifiable niiitter — in Lard, 0.2.'!',' ; Cotton-seed oil, 1.04'^; Olive oil, O.To<; Rape oil, 1.00^^'; Coddiver oil, l.;!!'--,' ; Japan wax, 1.14;^'; Spermaceti, 40.d4f,' ; Peeswax, na.oS;-^ ; Rosin oil, 98.72'^; i\Iineral oils, 99.90;/. Estimation of Free Fatty Acids in Fats.' — Tlic plan of ' A summ;iry of llje fractions of coiil-lar dislillal ion is given under Plionol. 'Geissler, 1878: Dixg.pijl. Jour., 227, 92; Zeilsrh. unal. Cln'in., 17, ;i!):!; Jour. Chevi. Soc, 34, 534. Bubstyn, 1872. Uaueu, 1877. Wieuehmold, 278 FATS AND OILS. Geissler, an ethereal solution of the oil being titrated with stan- dard alcoholic alkali, to the neutral reaction of phenol- phthalein, is generally applicable, and capable of variation to meet teclmi- cal demands. As a solvent for the fats and oils, etlier or alcohol- ether may be employed, or (Geogee) 5 to 10 parts of hot alcohol may be used. The solvent must be free from acidity. Ether is neutralized for this purpose by adding to a portion a drop or two of phenol-phthalein solution, and then drops of alcoholic al- kali, until the color of the indicator begins to appear after shak- ing. For one part of the oil, weighed for estimation, 2 or 3 parts of ether are usually suihcient. The alcoholic alkali solution may be made with good alcoholic potassa, and alcohol free from fusel oil (if need be, liltered through animal charcoal), and in most cases should be very dilute, approximately 20th normal, or weaker. After titratiug the ethereal solution of the weighed quantity of the oil, with the alcoholic alkali, just the required quantity of this is again taken and titrated with standard acid. Generally decinormal acid may be used, or a solution of acid in which 1 c.c. corresponds to 0.001 gram of the fat acid under estimation. It is better to express the results in percentages of fatty acids in the fats examined, provided a representative acid can be taken — as n per cent, of free acid as oleic acid. Bukstyn's numbers, or degrees of acidity in fats, are the c.c. of normal al- kali solution neutralized by 100 c.c. of fat ; or (Kottstoefee) 100 grams of the fat. Aechbutt distils a mixture of the oil with purified methyl alcohol, repeating once, and titrates the distillate. Separation of Covimon Resin from Fats and Soaps. — A satisfactory method, trustworthy for either Quantitative oi' Quali- tative purposes, is that of Gladding,' dependent on ether-solu- bility of the silver salt, and corresponding to the separation of oleic acid by ether-solubility of its lead salt. Fatty salts of silver are insolulile, resin salt of silver soluble in ether. — The free fat acids are to be obtained, with the rosin, neutral fats being first saponified, soaps being treated with acid, and the total free fatty acids washed with water and dried if need be. For quantitative separation the directions are as follows : About 0.5 of the fat acids is accurately weighed into a small flask, and 20 c.c. of 95 per cent, alcohol added for solution. A 1877. KoTTSTORFEK, rancid butters, 1879: Zeitsch. anal. Ohem., i8, 436. Grogee, 1883: Di7ig. pol. Jour., 244, 307. Aechbutt: Repert. f. anal. Ghem., 4, 330. ' 1882: Am. Chem. Jour., 3, 410; Jour. Ghem. Soc, 42, 663; Ghem. News, 45, 169; Zeitsch. anal Chem., 21, 585. SEPARA TION OF RESIN. 279 drop of plienol-plithalein is added, then a saturated alcohol solu- tion of caustic potash is added by drops until the color of an alka- line reaction is olitaincd after ajiiitation, when one or two drops of the alcciluilic jiotash are a(lay, 130 ; American, 156. Cotton- seed oil, relined, 24.6; rape-seed oil, brown, 20; rape-seed oil, colza, 17.6. Olive oil, highest, 8.7; lowest, 8.2. Linseed Oil.' — Leinol. Huile de lin. Flachsol. Chiefly the triglyceride of Linoleic Acid (p. 249),C3H5(CieH3702)3=794.— A tixed oil expressed from flaxseed, the seed of Linum usitatis- simum, of which it should form as much as 25 per cent. See Drying and jN'on-dryiug Oils, under Fats, p. 281. a.— A yellowish or yellow oily liquid, of the sp. gr. about 0.936 (r. 'S. Ph.), at 15° C. 0.9347 (Schijblee), 0.9325 (Sou- cheee), 0.930-0.935 (Allex). Specihc gravity of the total fat acids, at 100° C, 0.8599 (Archbutt and Allen). Congeals at — 16°C. after a few days (Gusseeow); -27° C. (Chateau). Melts at — 16° to — 20° (Gi.assxee). The total fat acids con- geal at 13.3° C. (Hubl) ; melt at 17.0° (Hijbl). Boiled Linseed Oil has sp. gr. 0.940-0.941. h. — Linseed oil has a slight peculiar odor and a bland taste. c. — Insoluble in water; soluble in 5 parts absolute alcohol, in 1.5 parts ether. d. — Linseed oil, treated with nitrous acid, does not yield elaidin. Mixed with concentrated sulphuric acid, as directed under Drying and Kon-drying Oils, Distinctions between, p. 282, very high numbers are obtained. Treated with iodine, large ab- sorption capacity is found (pp. 258 and 259). For oxygen-ab- fiorption see Drying Oils, etc., p. 2S3. e, f. — For Separation and Yal nation of Linseed oil, see Dry- ing Oils, p. 281, and Linoleic Acid, p. 249. g. — Linseed oil is adulterated with cotton-seed oil, mineral ■ Schaedler: "Technologie der Pette und Oele," 1883, p. 494. Benedikt, " Analyse der Fette," 1886, p. 215. OLIVE OIL. 285 oils, rosin oil, niger-seed oil, rape-seed oil, hemp-seed oil, and fish oils. Mustard, rajie, and hemp seeds are gathered with flax-seed. Speeitie gravity of mineral oils is lighter than of linseed oil, nsu- ally from O.SSO to 0.905 ; while resin od is lieavier, O.iHI to 0.99. ISTon drying oils are indicated by the elaidin test, by not generat- ing the full quota of heat with sulphuric acid, by not absorbing the proper amount of oxygeu, and liy lower iodine numbers, ac- cording to directions given under Drjnng Oils, p. ^s]. Presence of hydrocarbon or mineral oils is sliown l>y their non-saponitica- tion, Sometimes revealed l)y fluorescence, and sometimes by distil- lation, as speeitieids all insoluble, and requiring some time to solidify at 4.4° C. (40° F. ) The high density was the obvious indication that it w;is not lard alone. The sample represented a grade apiiearing on the market. — Alleged adulteration of " prime steam lai-d" with cotton-seed oil products, in Chicago in 1S8,S, was made tlie dcca- sion of a protracted trial before the Board of Trade of the City of Chicago." ^Analyst, 7, 9:1 ' The evidence nf a good number of American chemists in tliis c.'iso, with proceedings iind findini,'^, was published Viy the Board of Trade: "^IiCcoch, Everinghani & Co. vs. I'^nvler Brothers," pp. 2S0, 18SI1, Cliic.'iiJio 8,-imples of known admixture of lard with tallow, lard with ciillnn-seed nil. imd of |)ure lard were submitted to four chemists and to one microseupist for itnalvsis The reports were not in accord with eacli other, and lo a tji-r.'it cxleut failed of their object. A method of separalion by use of ali'ohol-cllier as a solvent was 292 FATS AND OILS. Respecting Microscopical Examination of lard and other fats, Dr. J. H. LoNu has contributed a valuable summary/ with origi- nal micro-photographs. Laed Oil. — SchnmlzoJ. Speckol. — By pressure of lard at about 0° C, the residue being the Solar Stearin or Lard Stearin of the candle industry. Sp. gr. of lard oil, 0.915 (Allen). Sa- ponification mimber, 191-196 (Mooee). Tallow Oil. Talgcil.— By pressure of tallow at low tempe- ratures, mucli lower than are employed for oleomargarin. Oleomaegaein. — This term has been primarily applied to a product of purihed fresh tallow with rejection of a good part of its stearin. The invention of Hippolyte Mege, of Paris, France, prescribed that fresh suet should be immersed in a brine of com- mon salt and sodium sulphite or otlier addition, then crushed be- tween rollers and washed, and digested at 103"^ F. (39.4° C.) with sheep's stomachs and calciimi biphosphate (U. S. patent, 1873), at animal teuiperature with infusion of a pig's stomach in acidu- lated water (Br. patent, 1809 ; Bavarian patent), with fresh sheep's stomachs and a very little carbonate of potash in other specifications. By specifications at the 103° F. or at the animal temperature, but practically at 112° F. 07' the necessary tempe- rature, the digested tallow (freed from the cells) melts, and is decanted. It is now allowed to cool to some adjusted tempera- ture (86° to 98" F ), and kept at rest to " crystallize '' out " stearin in the form of teats." The decanted liquid is further (or instead of the operation of "crystallization") cooled to solidify, and then subjected to pressure, either in a press or in a centrifugal ex- tractor. The liquid product was oleomarscarin.' much employed, as were also the color tests of Chateau. One witness only- states the use of Kcittstorfer's method, and no mention was made of determina- tions by iodine numbers, or by the congealing and melting points of the fatty acids after removal of oleic acid. Separation of oleic acid by action of ether on the lead salts was cited by several of the witnesses. Prof. Remsen stated that, in his opinion, " the limits of variation in the composition of lard " had not been ascertained so as to enable a chemist to determine the question of its adultera- tion. ' "Some Points in the Micro-Chemistry of Pats." John H.Long, Sc.D. Chicago Academy of Sciences, 1885. - Patents were issued in 1871 in the United States to H. Bradley and to W. K. Peyrous to make the grosser animal fats eq\ial to the best lard, for cooking purposes. In 1873, besides the V. S. issue of the Mege patent, a patent was is- sued to E. Q. Paral'e for the manufacture of an article designated as "oleo- margarin." Further see F. Bondel. 1874: " Extract from report of Mege- BUTTER. 293 The transformation of this into " artificial butter " was under- taken by Mege through churning witli niillv, or cows' udders, or other treatment." In tliis country manufacturers of oleomarga- rin have been practically free from any restrictions of patents, and have conducted the details according to methods governed by the discretion of each producer. Indeed, everywhere the general essentials consist most often in melting at 60° to 65" C. (Ii0° to l-t;»° F.), decanting to clarify, -'crystallizing" at 35° C. (95^ F.), and pressing at this temperature for "prime margarin" or oleomargarin, the solid residue l)eing known as "prime press- tallow," and used mainly for candles. At the present time lard is extensively treated for a product corresponding to oleomaig'arin, and used in butter substitutes. In these, also, cotton-seed oil, or fractions of it, sesame oil, and cocoanut oil have been employed in some quarters. Oleomargarin proper, from tallow, has given the following numbers :__Sp. gr. at 15° C, 0.924-0.930 (Hagee) ; at 100° C, 0.859 (Konigs). For percentages of stearin in oleomargarin, corresponding to degrees of congealing point of the total fat acids, see table at p. 272. Iodine number, 55.3 (HiijBL), 50.0 (Moore). Ilehner's number (per cent, insoluble fat acids), 95.56. Saponification number of Kottstorfer, 195 to 197.4. Keichert's number, 0.4 to (».6 (Coknwall). Butter.' — The immediate constituents are four: water, curd or casein, salt, and fats. Of these the following percentages occur: Wati'r : proper maximum of good butter, 12,'i (Hehnkr, Wiley). Of 19 samples reported by the Agricultural Dept. the lowest percentage of water was 7.34 ; the highest, 14.31 ; next highest, 14.06,'^. Of 49 samples reported by tlie Board of Health MouRiEZ to the Board of Heallh of the Department of the Sc-ine on the Product named 'Artificial Butter,'" Amer Cliemisl. "Sevi York, 4, 370. MioE-Mou- RIEZ. 1872: 3fnnifnir Scieti/ifique, [3], 2, No. 369; Amer. Cliem.. 3, 231. H. A. MoTT, 1876: "Manufacture of Artificial Butler," Amer. C/ieiii., 7,233. Agricvlhire of Peiivsi/lniiriia Repurla, 1885: pp. 21'.)-20.'i. "Second Annual Report of the New Ynrlc State Dairv Commissioner," 1886, pp. 190, 312. ' Further on tliis subject see Tidy and Wkixer, 1883: Anidij.st, 8, 113. ' Hebner and Angell, 1877: "Biillcr. its Analysis and Adulterations." A. W. Blyth, 1882: "Poods," etc., pp. 2S3-.S0.1. Fox and Wankltn, 1884: "Anal, of Butler," AimUifit, 9, 73. Bell, method bysp. {,'r., 1870: Phur. ,Jom-.. [3], 7, 85. Eastcoubt, sp. gr., 1876: ° C, and at least 50 c.c. of filtrate obtained. Specific gravity, -At 15° C, 0.92(1 (Cassamajoe), 0.!»M75 (A. W. Blyth), Oi»3(l-U.tHO (Hagek); at 37..s°C. (100° F.) (water at same=l), 0.011-0.913 (Bell) ; at 100° C. (water at 15° C'.= 1), 0.865-0.868 (Konigs) ; at 100° C. (water at ](K)° ('. = 1). 0.901- 0.904 (Wolkenhaae) ; at 40° C. (water at same = 1), 0.912 (Wiley) MeJt'nuj I'diiit. Not well defined. Of lutter, softens at 2 1..° t.i 31.1° C, and melts at 24.4° to37.2''('. (Paekks and Bkown) ; bj' the rising of a light glass bulb, mean 33.7", by clearing of the liquid, mean 35.5° C. (IJabsall); l)y the sinking of a weighted bulb, average of 24 samples. 35. .0' C'. (IIehner and Angell) ; by rising in capillary tubes imniei'sed in water, 31° to 36° C (Heiscii); by the running of a solidified The simple glyceride tributyrin does not ii|i])('iir to be present in bullrrs. Conjugaled glyceride's, such as CaHiCCioHs.OjiilCiHiOj), are inferred to be llie sources oC the butyric acid ol saponification. Mr. JIeh.neb, however, presents another view : " lioth the dipalmitale-inonobutyrate and the diolcate-niono- butyrate would yielil less insoluble acids than iiic found in juaclire, the former 80.2 and the latter 84.G per cent. But a mixture of compound etiicr.s sucli as would be obtained by substil iiting in the //-/pal mil ate or/r/olcaleof i;lyceryl one atom of the acid radic-al by the radical of butyric acid would very appniximalely yield such proportions of insoluble and solulile fat acids as lue actually found." It is to be oli.M'rved that the question is couiplic;i(ed by the presence of volatile fat acids of hiv^nv molecular weights than butyric aciil. At all events, the vcihi- tile fat acids obtained from 100 parts of butter fat average about parts. 300 FATS AND OILS. from 2 5 gram of fat (Keicheet), 14.0; not less than 13.0 (Meissl). Iodine number of HIibl, 26.0 to 35.1 ; fat from very old buttei-, 19.5 (Mooee). Butter Substitutes. — Oleomargarin is described at p. 292, with some description of treatment adopted to give it a sensible resemblance to butter. At present prepared lard fat (p. 290) is used as much or more than prepared tallow fat. Frequently a vegetable oil is used with either lard fat or oleomargarin proper (tallow fat). The vegetable oil most used is cotton-seed oil (p. 287) ; after which are to be named sesame oil and cocoanut oil. Of these substitutes — two animal fats and three vegetable fats — only cocoanut oil approaches in composition to butter fat. It must be remembered that the fats and combinations of fats presented as substitutes for butter are subject to constant change. The Report of the Dairy Commissioner of the State of New York for ISSG says " the only materials used, a.ccording to the statements of the manufacturers, are oleomargarin (' oleo-oil '), lard, cotton-seed uil, sesame oil, and annatto." The term " but- terine" has been more commonly applied to the mixture of deodorized lard and butter prepared by cliurning with milk. " Suine " is a term applied to a grade of butterine with very large proportions of lard. The work last mentioned describes, besides tlie oils just named, those of peanut (ground-nut), ben, mustard, colza, rape, cameline, cocoanut, cocoa, palm, cacao, and bone. Principal Chemical Methods of Estimatinn of Butter-Fat. (1) Parts Insoluble Fat Acids in 100 parts Fat. Hehner's number, pp. 250, 256. (2) C.c. ^,5- alkali for Volatile Fat Acids in 2.5 grams Fat. Reichert's number, p. 253. By Meissl's method, p. 253. (3) Milligrams KOH to saponify 1 gram of the Fat. Kiitts- torfer's number, pp. 254, 257. Perkins's combination plan, p. 255. As a single estimation, that denoted by Reichert's number (probably with Meissl's manipulation) is here unhesitatingly re- commended in preference to any other. But Hehner's number is of nearly an equal value, and next is ranked the number of Kottstorfer, the latter being of the three the most easily ob- tained. — Respecting (4) indications by specific gravity, see p. 261, (5) Hiibl's iodine numbers, p. 258. (6) The melting and congeal- ing points of butter substitutes may or maj' not differ from that of true butter fat. Respecting the obtaining and applying of data of melting and congealing points, " the sinking point," and BUTTER FAT. 301 " the point of clearance," see p. StlTi. (7) The percentage of •casein, estimated by moist combustion for nitr(i.5, and 85 are subject to chemical estimations of the per cent, of insoluble fat acids in butter fat and in adulterating fats, and die i)er cent, of butter fat in true butter. The per cent, of insoluble fat acids is itself tlic best statement of results by Ilelmer's uictliod, and it should be given, for information of those who can unck'rstand it, while the calcu- lated per cent, of true butter is given only when rc(pured, and may be accompanied with a statement of the conditions on which it is based. I'lic conversion of tlie pei'centage of butter fat into that of entire butter is mcjre properly made by use of the actual pei'centage of total fat found in the butttu- as sold, instead of the g;eneral average figure, 85, abo\c assumed. Ihit even with the use of this factor from the butter in (picstion, there remains the 'Seep. 2!i4. 302 FA TS AND OILS. uncertainty as to how much of the water in the sample was in- troduced as a part of the true-butter fraction, and how much was introduced as a part of tlie oleomargarin fraction, or was due to manipulation of the mixture. Therefore the opinion is here given that the simple figure known as Hehner's number is the best expression of results by Hehner's method (See the follow- ing corresponding discussion of interpretation of Kottstorfer's number, p. 304). A table of Hehner's numbers of the principa} fats concerned in butter adulteration is given on p. 256. Of 29 true butters reported upon by the Department of Agriculture at Washington,' hve gave between 88.5 and 89.0 per cent, of inso- luble fat acids, three Alderneys gave from 89.0 to 89.26 per cent., and one, an Alderney, gave 89.89 per cent. The Food Analyst of the Pennsylvania Board of Agriculture, Prof. C. B. Cochran, found the extremes of fixed fat acids from fat of 25 genuine but- ters to be 86.7 to 87.7 per cent." Rancid Butte'^'ii give nearly the same percentages as fresh butters (Fleischmann and Vieth), the slight differences being in the direction of an increase. (2) Interpretation vf results by Reicherts JEstimatiun.^ — The c.c. of decinormal alkali to neutralize the volatile acids of 2.5 grams of fat. Each c.c. decinormal alkali indicates 0.0088 gram of butyric acid ; and 0.0088 gram butyric acid in 2.5 grams of fat is equal to 0.00352 gram butyric acid in 1 gram of fat, or 0.353 in 100 grams of fat. Then, Keichert's number X 0.352 = per cent, of volatile acids (as butyric acid) in the fat ; and per cent, butyric acid -f- 0.352 ^ Reichert's niimber. Reichert found true butters to give numbers from 13.55 to 14.45, average 14.0, and declared any butter giving less than 12.0 c.c. must be adulterated. Dr. G. C. Caldwell reported to New York State Board of Plealth estimations of 27 samples of butter yielding Reichert's numbers from 12. 7 to 15.5. Messrs. "Waller and Martin (Report New York State Dairy Commis- sioner, 1886) obtain, from 26 American butters, on first 50 c.c. of distillate, numbers of Reichert's method from 12.2 to 16.3 as ex- tremes. They also carried eight additional distillates, in exten- sion of Meissi's plan, by 'ivliicli they compute that only from 75 to 85 per cent, of the total volatile acid comes over in the first 50 c.c. Prof. C. B. Cochran, "West Chester, Pa., Food Inspector of ' 1884: p. 63, Report of the Chemist, H. W. Wiley. ' Uijpublished report communicated to the author. ° Directions fur estimation and bibliography, p. 253. BUTTER FAT. 303 the Pennsylvania Board of Agriculture,' lias found the extreme minimum of the Reichert's numbers of known genuine butters to be 12.5 (c.e. of tenth-normal sol. for 2J grams fat) ; and this che- mist holds that Reichert's number 11.5 is the proper minimum limit to govern an analyst in condemning butters inspected by law. He has finally come to rely almost exclusively upon the Reichert's numbers. In Reichert's own analyses lard gave 0.30 ; raw tallow, 0.25 ; rape oil, 0.25; oleomargarin butter, 0.95. Cocoanut oil gave 3.70. Reichert proposes this formula for calculation of per cent, of true butter fat in an admixture of fats : (Reichert's number — 0.30) X 7.30 ^percentage of true butter fat. The probable error = ±_ 0.24 X (Reichert's number — 0.30). ]\Ieissl, using his modiiication (p. 253), places the minimum limit of the Reichert number at 13. R. W. Mooee (1SS5 ") re- ports the following tabulated comparisons of chemical data for the distinction of butter from its substitutes, with discussion of the various methods, and recommends Reichert's method, espe- cially when cocoanut oil is in question, lliibl's number gives the percentage of iodine taken (p. 258) : • Numbers of HBHNER. kSttstoe- FER. HiJBL. BKICHEET. Butter, samples Oleomargarin, samples. . . Butter, 50^ j 86.01 ( 86.49 95.56 • 89.50 227.0 224.0 197.4 195.0 227.5 19.5 38.0 50.0 50.0 35.4 13.25 13.1 0.6 0.4 Oleomargarin, 27.5^ Cocoanut oil, 22.5^ 8.7 The specific gravity of the cocoanut oil used was 0.9167 at 37.7° C, " which is sufhciently high to bring the mixtures above the sp. gr. of 0.911, which is that of butter. Waller and Martin (1886) found cocoanut oil to give a Reichert's number of from 2.7 to 3.7. ' [Jnpublished communication to the author. ' Jour. Am. Chem. 80c., 7, 188; Ar.alysf, 10, 224. 304 FA TS AND OILS. Meissl (1S79) found tliat soft butters yield higher propor- tions of volatile acids than hard butters. Butter oil gives higher numbers in Keichert's nicthod than entire butter. Rancidity reduces the quantity of the volatile acids of butter. The quantity of volatUe fat acids hy Heicherfs method is by no means identical with the quantity of soluble fat acids, though the latter should include the former. It will be observed that insoluble fat acids are filtered out of the distillate, if obtained in it, in Reicliert's operation. A good number of the analysts of butter practise the estimation of its soluble fat acids by titration of the filtrate and ^vashings from the insoluljle fat acids. With- out doubt these results have value. Along with Hehner's method they are easily obtained in a combination process. Di- viding per cent, butyric acid by 0.352, the quotient may be com- pared with Reichert's number. It is believed, however, that Iteichert's estimation of volatile acids has greater constancy than an estimation of the soluble fat acids, and therefore the combi- nation plan of Perkins (p. 255) is given in this work ii)stea8. In Kottstorfer's conclusion (1879) a number not lower than 221.5 indicates unadulterated butter, this being the lowest limit of true butter. The highest limit he placed at 233, and the ave- rage 227. For oleomargarin the number 195.5 was taken as the average, and for lard the same. If a number (ib) be lower than 221 5, the percentage of oleomargarin (a;) is found by the for- mula, X = (227 — 7i) 3.17. Tliat is, if the limit number be overpassed by any butter in question, its amount of adulteration is judged by comparison BUTTER FAT. 305 with the average number of true butter — a plan corresponding to that followed under Heliner's method. Then we have as data for calculating the percentage (x) of adulterating fat, from Kcitts- torfer's number (/i) for any mixture of fats : 227 — l'J5.5r=31.5) : (227 — w)::100 : a; And The average number of any adulterating fat in question is to be sulistituted for 195.5 ; and the number 227 is to be held subject to correction as the average number for true butter. The difference 31.5 may be varied by ± 5.75 in cases of extreme composition of true butter fat, causing ±_ 18;^ difference in the interpretation. Kancid butters gave Kottstorfer a number, for the fat, 1.5 lower than fresh butter. Mr. WiGNEE, in 1879, stated that "any butter fat which re- quires near 22.6f;; KOH for saponification [number 226], as de- termined by the titration process, may be safely i)asscd as gen- uine ; but any lower result should be checked by a further analysis." (4) >Hj)ec[fic Gravlfi/ as' a inediis of <]hthi') the inactive aiuyl alcohol of fusel oil is soluble in about 50 parts of water at 14° C, and less soluble in water at 60° C. Iso-butyl alcohol is .soluble in 10 parts of water at 15° C. One part of inactive arnyl alcohol takes up about 0.08 parts of water; one part of iso-butyl alcohol, about 0.15 jxirts of water. Fusel oil is free! y soluble in ether, chloroform, and the other im- miscible solvents of general use. Of the nmyl sulphat^ifi of Ixt riuTn^ that formed from inacti\c amyl ah.'ohol is two and a half times less solul)le in water than is that from active amyl alcohol — a dif- ference made available for separation of these isomers. d. — //; the qualltaiive idenivjirailiyn of fanel oil the odor, and the effect of inhalation, are the means in most common use. In testing fusel oil in liquors or commercial alcohol the ethyl alco- hol is made to evaporate before obtaining the odor. The Br. Ph. and U. 8. Ph. directions for examination by odor are given under h. Separation hy an immiscible solvent, as described un- der e, may he adopted preparatory to any qualitative examina- tion. In ordinary analyses of alcoholic liquors or commercial alcohols, the ethyl alcohol has to be separated by careful distilla- tion for the estimation of " strength," and the residue of such distillation, while warm, is to be examined for odor. Concentrated sulphuric acid, on c()nt:iet with fusel oils, en- ters into formation of aniylsulphuric iicids, HC5lljj^S( )^, present- ing a red color.' According to Vitali {loo. cit.), when the sul- phuric acid is added to a smaller quantity of fusel oil the color is red, growing browii-reil on standing and on heating. Equal volumes of the amyl alcohols and the sulphuric acid gi\e a dark and dull red color ; but with an exc^et^s of the fusel oil differ- ent tints are obtained, cherry-red, violet, azure-blue, and green, in the ordei' of the increasiug excess of fusel oil. W'^hen to a drojD or two of sulphuric acid, on a white porcelain sui'faee, an equal volume of the fusel oil is tii'st added, and then additional portions of the latter, cheriy red iiml violet tints aiv obtained, and at the proportions der Phar., [3], 21, 964; Zeitsch. anal. Vlwm., 23, 42(;; Antilij^il, 9, 190. 3i8 FUSEL OIL. as stated under e, and as so applied the test is trustworthy for negative results showing the absence of material proportions of fusel oil. But inasmuch as numerous non-volatile bodies give colors with sulphuric acid, an indication of the presence of fusel oil should be verified, in this test, bj' applying it to a fractional distillate from the liquor or commercial alcoliol under examina- tion — a distillate obtained between about 120° and 134° C. For the qualitative use of Maequaedt's plan of separating amyl alcohols directions are given below under f. This method is very delicate. The odor of the valeric acid is highly distinc- tive. — The reaction of Joeissen, obtained by mixing with a lit- tle colorless aniline oil and a few drops of sulphuric acid, for a fine red color, depends on the presence of furfurol (aldehyde be- tween furfury] alcoliol and pyromucic acid) present in fusel oils.' — Sevalle (1881) determines the presence of fusel oil by turbi- dity of its alcoholic mixture when heated. — Traube '' tests brandy, after dilution to about 20 per cent, of strength, by the height to which the liquid rises in a capillary tube, as compared with a pure spirit of the same strength. — The etherification of amyl al- cohols, to form esters of acetic acid, has been included among methods for recognition. The liquid is warmed or distilled with alkali acetate and sulphuric acid. The odor of amyl acetate is that of pears. This odor, however, is quite liable to be covered by that of acetic acid or ethyl acetate, so that caution should be observed in interpretation of the result. e. — The separation of ftisel oil by distillation gives prac- tically conclusive results, but is certainly not without waste. Sep- aration hy immiscible solvents is generally employed. Betelli' adds to a certain (quantity of the commercial alcohol six or seven times its volume of water, and shakes with chloroform enougli to make after subsiding a very small layer, which is drawn off and evaporated for test of the residue. With only 5 or 6 c.c. of the alcoliol, and 15 to 20 drops of the chloroform, 0.05 per cent, of fusel oil was detected, the final test being that of etherification to amyl acetate (" pear oil " ) by digesting the residue with al- kali acetate and sulphuric acid. Before applying the immiscible solvent it is proper to reduce the concentration of the ethyl ' FiiRESTER, 1882; Bev. d. chem. Ges., 15, 330. '1886: Ber. d. chem. Oes., 19. 893; Jour. Chem. Soc, 50, 743. Follows a report on relation between capillarity and molecular weight, and on specific capillarity, 1885: Jour, prakt. Chem., [3], 31, 177, 514; Jour. Chem. Soc, 48, 866, 1033. 2 1875: Ber. d. chem. Ges., 8, 72; Zeiisch. anal. Chem., 14, 197. FUSEL OIL. 319 alcohol, either by distilling it off or by adding water. See the directions given below under/". f. — Quantitative. — For the estimation of fusel oil the method of Maequakdt' is here given: The fusel oil is separated from a diluted alcoholic liquid by shaking out with chloroform ; the amyl alcohol is oxidized to valeric acid; the acid is taken up by barium carbonate, and the barium salt is estimated, to repre- sent the quantit}' of amyl alcohol oxidized. Of tlie alcoholic liquid under examination 150 grams are to be diluted with an equal volume of water, and agitated with 50 c.c. of chloroform (of ascertained purity) for about a quarter of an hour. The aqueous layer is separated and again extracted with 50 c.c. of chloroform for the same length of time. The operation is re peated the third time. The united portions of chloroform are treated, in a strong flask, with a solution of 5 grams dichromate in 30 gi-ams of water, and 2 grams of sulphuric acid, digesting for about six hours with frequent agitation while tliu flask is well corked. The contents of the flask are then distilled until about 20 c.c. remain, when this residue is diluted by addition of about !S0 c.c. of water, and again distilled until only about 5 c.c. remain. The entire distillate is then digested with heat for half an hour with barium carbonate, an erect condenser being employed to return the distillate to the flask. The chloroform is tlien sepa- rated by distillation, and the aqueous residue concentrated tti a volume of 5 c.c. The excess of barium carbonate is filtered out, and the filtrate with the washings evaporated in a weighed dish on a Wiiter-bath to dryness. The residue is weighed, and after- wards dissolved in water and a few drops of nitric acid, and made up with water to 100 c.c, of which 50 c.c. are taken to es- timate the barium, and 50 c.c. to estimate the chlorine (derived from the chloroform by action of the dichromate). Tlie quantity of barium combined with the chlorine is calculated, and deducted from the total barium in the 50 c.c. From tliu remaining quan- tity of barium the quantity of valeric acid is calculated, and from this the quantity of amyl alcohol. Then BaS()4 : 2CgII]^.,0 :: 2.32.8 : 170 ::1 : 0.7560. And the weight of barium sulpliutc X 0.756 = the weight of amyl alcdhol. For exact results the chloroform used is to be purified by subjecting it to tlie operation as described — treatirient with s(.ilu- tion of dichromate and sulphuric acid, distillation, digestion of 'Ij. Marquardt, 1HH'3: Bn-. d. rlirm. (ten., 15, 1370, KKil ; Ani:hi«l . 8, 106; Jonr. 80c. Chevi. Iitd., i, Xii, ;!T7; Jniir. Uhem. Sar., 42, 1235, V.i'il. A favoiiible repoct upon Marquardl's ineLliod is given by (i. LuNOB, V. JIeyer, and E. Souulze, 1884: G/iem. Cod., p. 854; Jour. C'/iem. Soc, 48, 708. 320 GALLIC ACID. the distillate with barium carbonate, and redistillation. To pu- rify ordinary chloroform it is necessary to repeat the process several times. In the qualitative use of the test 30 to 40 grams of the spirit are diluted with water so as to contain 12 to 15 per cent, of al- cohol, and the liquid shaken up with 15 c.c. of pure chloroform. The chloroform solution is washed with about an equal volume of water, and, after the latter has separated, is evaporated to dry- ness. To the residue are added a little water, one or two drops of sulphuric acid, and permanganate of potassium enough to give a red color after 24 hours. The estimation of fusel oil by measurement of the increase of \-ohime of the chloroform layer, after shaking out, making comparison with a standard spirit, has been undertaken by B. Rose, and advanced by Messrs. Stutzee and Reitmaie,' but the method is not well sustained." The quantitieH of fusel oils present in alcoholic liquors have not been generally obtained upon trustworthy data. In certain whiskeys there were obtained, in the analyses of De. Dupee, from O.IS to 24 parts of amyl alcohol to 100 parts of ethyl alcohol. N. P. Hambeeg ' has given figures for the fusel oil in beer as follows : 1.14 gram of fusel oil in 100 liters of the beer, or about 0.U0114 per cent. GALLIC ACID.—C-IIeO- = CgHo(C0„H)(0H)3 = 170. A trihydroxj-benzoic acid [(JO3H : OH fOH": OH = 1 : 3 : 4 : 5]. Gallussaure. — Found in nutgalls. sumach, tea, and, accompany- ing tannins, in a large number of plants. Gallic anhydride, as digallic acid, occurs in gallotannic acid, and gallic acid is a natu- ral fermentation product of certain glucoside-tannins. It is in use in medicine, as a reducing agent in photography, and in hair dyes. It is not a tanning agent. Gallotannic acid, in the human body, is soon converted into gallic acid. The gallic acid of commerce is wholly manufactured from the tannin of galls. Gallic acid, as a separate solid, is identified by its sensible properties and decomposition products («) ; in solution, by its ' Summary by Uffelmaxn, 1886: Ding. pol. Jour., 261. 439; Jour. Chem. Soc , so, 1079. B. Ro.sE. 1885; Archiv d. Phar., [3], 23, 63. ■•"Lunge, Meyer, .'ind Schulze, 1884: ./m/r. Gheni. Soc, 48, 709. ' 1885: Trans. Royal Acad. Stoclcholm, ; Sclimidl's Jahrbucher der Medkin, 201, 27. GALLIC ACID. 321 reactions with iron salts, lime, and antimony, and its reducing power ((/). It is distingnislied fr(uii tannins l)y non-precipitation of gelatin, alkaloids, and antimony in pi'esence of ammonium chloride, i^i parai'ionx from tannins, various aciils, and fnjm metals are imlicatei.! in t?, methods of estimation in /', and tests for purity in H!. (^•±lO='-ill>=F"), a white or yellowish white subli- mate of pyroi,^alliil appears, iu droplets, crystallizing on cooling: C'-.Ily()5 = CVla()3 47(-'0.. A dark residue remains. Heated L[iuekly, in a i)orcelain capsule, at about a.">U" C. (481!' F.), meta- gallic acid, ('ell^**.^, is formed, in a black lustrous residue, sol- uble in strung alkali solutiim, with dark-brown color. Heated very gradually, with concenti'ated sulphuric acid, in a test-tube, to about l.JO^C. (?AY},' F.), the mass turns wine-red to carmine- red. If now cooled and poured into water, the latter will he colored yellow- brown, and a red-brown ])recipitate of rufiaallol (ruligallic acid) partly crystalline (in rhomhohedrons) will ap- pear. If the jirecipitate be waslied and driei- tate alkaloids, gelatin, albumen, gelatinized starch, or solution of tarti-ate of antimony and jiotassium with chloride of ammonium (distinction from tannic acid) " (U. IS. Ph.) GALLOTANNIN. See Tannins. GLYCERIN. Glycerol. 031^803 = 92. (("3lI-;)"'(0II)3.— Propenyl, ( 'gllg^CIL, .CIl .C'll,, , is a residue of propane, the third memlicr of the marsh-gas series. Glycerin is pidduced, along with candle-manufacture and the production of the fat acids ("stearin '" and "olein"), l>y saponification of the fats, with Avater as superheated steam, or with lime, or with sulphuric acid. It occurs also among the products of the alcoholic fermentation of sugar. Cilycerin taken alone is recoipdzed by its sensible properties {(():, in dilute forms or in certain admixtures it is re\'ealed by the bead-test with borax, its jiower of neutralizing boracic acid, and the odor of its vapoi's when strongly heated {d). An a )v- (luc'nitj (iqeiit it afl'ects permanganate promptly in alkaline mix- ture, sciirceh' at all in neutral oi' acid liquids, and does not alter Fehling's solution. It is .w'j(«ov^/«/ from substances more \'ola- tile than watei' by their distillation, and fi'om non-\'olatile sub- stances by its own distillation at a, heat a little abo\e that of the water-bath; from matters insobdjle in alcohol, by use of this sol 324 GL YCERIN. vent, best by use of lime and alcohol {e). It is estimated gravi- metricallv hy careful evaporation with alcohol-ether ; volunietri- cally by the ]K>nnanganate reaction, forming oxalic acid (/'). Tests and authorized stiinditrdi of j^ wit 'J (f/, p. ?>2S). (L — Glycerin is a colorless, clear, syrupy licpiid, capable of crystallization in low winter temperatures, taking forms of the rhombic system, or congealing in white, crystalline ni;isses, nearly or quite anhydrous, the melting point being 22° C. Specific gravity at 15° C, taking water at same temperature as standard, i.26iC8 (Mendelejeff), l.-2iu>?' (Gerlach); at 15° C, taking- water at ()°C., 1.2('i3r)S ; at 17.5° G, 1.2ti2 (yxEOHMEEj. Glycerin is very liygniscopic, and at ordinary temperatures it vaporizes in only the slightest degree, but at lOU" (!. it v^iporizes or distils to a sensible extent. At this temperature and 7(iO uullinieters barometric pressure it has a vapor tension of 6-1 millimeters. At 290° it boils with partial decomposition, evolving vapor of acro- lein, C3H4O. Witli superheatetl steam at ISO'' to 200° C. it dis- tils completely. Evaporated in an dpcn dish at 150° to 200° 0., when perfectly pure, it leaves no residue iK'hind. Pleated in a capsule, at 1)2° 0. vapor rises almost imperceptibly, at 100° C cpiite perceptibly, at 130° C. abundantly, without irritatin^^ pro- ducts to a sensible extent at last-named temperature (Tklmble, 1SS5). b. — Glycerin has a pure sweet taste of much intensity, with- out odor. Undiluted it has a heating efEect when applied to the surface. (;. — Exposed to the air glycerin absorbs water, finally to the extent of about 50 per cent., and is soluble in all proportions of water and of alcohol. In mixture with water the volume is re- duced and the temperature raised, the greatest liberation of heat being obtained with 58 parts of glycerin to 12 parts of water, in which proportions the contraction of volume is about 1.1 per cent., and the elevation of temperature about 5° C. In ether, glycerin is slightly soluble, 1 part of glycerin of sp. gr. 1.23 re- quiring 500 parts of ordinary ether for solution. It is soluble in a mixture of 3 parts of alcohol and 1 part of ether ; also in a mixture of 2 vohimes of aljs(jlute alcohol and 1 volume of coni- nion ether. Not soluble in chloroform, benzene, or fixed oils. Soluble in a mixture of equal weights of chloroform and alcohol. Glycerin when pure is neutral to all indicators. Glycerin dis- solves the alkaline earths to a considerable extent, with chemical combination. If the solutions be charged with carbon dioxide the earths are mainly precipitated. With lead it forms the GLYCERIN. 325 glyceride, r.JT^^PhO.j, erjst.alliza,l)lo in fine white needles. So- dium glyeeridc, ( '.jll~Na().j, is a white, liyg)'iisci)[iic powde)-, resolved by water into glycerin and Kodiuni hydroxide. d. — " If a fused bead of borax on a ii)op of ])latinuin wire be moistened witli glycerin previously made slightly alkaline with diluted solution of soda, and aftei' a few minutes held in a color- less flame, the latter is tinted deep green." — (ilycerin abstrai;ts boric acid from borax, so as to affect the reaction to litmus. If a borax solution be coloreil (blue) with litmus, and a solution C(.in- taiuing glycerin, neutral in I'eaction, l)e also colored with blue litmus, on nu.xing the solutions a red color will lie obtained. "Warming restores the blue col(,r, but the red reappears when the liquid is cool again. — If a poition of glycerin be heated to boil- ing iu a dry test-tube, the characteristic ai'rid vnjxjrn of ticroi hi, will be obtained. If in aqueous mi.\ture, the L;lycerin must be concentrated for the test, \\'hicli is also renderetl more delicate by the addition of a little dry phosphoric acid or potassium bi- sulphate. Glycerin alone is not carbonized by heating with either of these agents. — If ii drops of glycerin (free from bodies carlionizeil by sulphuric acid) be mixed with l! drops each of melted phenol and sulphuric acid, and heateil somewhat ovei- l-{0° (A to the production of a resinous mass, and when cold am- monia be added, a fine carmine-red color will be obtained. Permanganate solution, aci3 + 2lv._,Mn^/)g = K.,( \,( )^ + KoCH )., + 4Mn( )., + ^W.Sd. Fehling's Solution is but veiT slightly rciluced b\ glycei-iu. A (juite concentrateil soluticjn of pure glycerin, boiled 10 ndnutes with Feliling's solution, and then set aside for lit to 4S hours, yields some precipitate of the cuprous hydroxide. JJut dilution of the glycerin with ten V(jlumes of water prevents the reaction. I'. — Si'jxiriifioiiH. — (ilycerin in watery mixture is not concen- trated by evaporatiitated by calcium acetate or ciiloride. The oxalate of calcium precipitated is esti- '1885: Analyst, 10. 205, from Chem. Zeit. An investigation of this and other methods, now being made by A. J. Baumiiardt and the author, will be communicated at an early diilc ^Fox and Wanklyn (1880: ('liem. News, 53, 15) take a quantity of iii;i,- terial containing not over 0.25 gram ut glyeenri, and add 5 grams of KUli. 328 GL YCERIN. mated at the discretion of the operator. But inasmuch as the precipitate is liable to contain, as impurities, calcium silicate and calcium sulphate, it is better to estimate the oxalate volumetri- cally with permanganate, or, after ignition, by titration with half norinal hydrochloric acid, using diniethylanilin orange as an in- dicator. The hydrochloric acid may be standardized by anhy- drous sodium carbonate. l()(i parts of NagCOg, or 72.8 parts of HCl, indicate OU parts of ILjC^O^, or 92 parts of glycerin. — In this operation methyl alcohol is used because ethyl alcohol, if employed, is not wholly expelled, and suffers oxidation by per- manganate in alkaline liquid with formation of oxalic acid. So- luble fat acids do not interfere. The method is applicable to any ordinary neutral mixture of glycerin. — Benedikt and Zsig- niondv obtained the following percentages of glycerin: From olive oil, 10.15-10.38; hnseed'oil, 9.45-9.97 ; tallow, 9.94-9.98- 10.21; butter, 11.59; Japan wax, 10.3-11.2; beeswax, 0. g. — Tests of ])urity. — The U. S. Ph. prescribes as follows: " Glycerin should be neutral to litmus-paper. Upon warming a portion of 5 or 6 grams with half its weight of diluted sulphu- ric acid, no butyric or other acidulous odor should be obtained. A portion of 2 or 3 grams, gently warmed with an equal volume of sulphuric acid in a test-tul>e, .«hould not l)ecome dark- colored. A portion of ;ibout 2 grams, heated in a small open porcelain or platinum capsule, upon a sand bath, until it boils, and then ignited, should burn and vaporize so as to leave not more than a dark stain (absence of sugars and dextrin, which leave a porous coal). A portion heated to about 85° C. (185° F.) with test solution of potassio-cupric tartrate should not give a decided yellowish-brown precipitate, and the same result should be oljtained if, before applying this test, another portion be boiled with a little diluted hydrochloric acid for half an hour (absence of sugars). After full combustion no residue should be left (metallic salts). Diluted with ten times its vohtme of distil- led wnter, portions should give no precipitates or colors when treated with test solutions of nitrate of silver, chloride of barium, sulphide of ammonium, or oxalate of ammonium (acrylic, hy- drochloric, sulphuric, and oxalic acids, iron and calcium salts)." " Shaken with an equal volume of sulphuric acid, no colora- tion, or only a very slight straw coloration, should result. When gently heated with diluted sulphuric acid, no rancid odor is produced. Sp. gr. about 1.25 " (Br. Ph.) " Sp. gr. 1.225 to 1.235. Heated in an open dish ti) boil- ing, and then ignited, it should burn without residue. It should HYDRASTINE. 329 not reduce ammoniacal solutiuii of silver nitrate, at ordinary tem- perature, within lialf an liour. Warniud with an e(|ual volume of sodium lij'drate solution (IS^o), it should not be colored, nor should ammonia be developed ; and i;'i'ntly warmed with diluted sulphuric acid, no disagreeable rancid odor should be gi\'cn " (Ph. Genu.) yp. gr. \.'1\-1. Undergoes comph'te combusti(in, leaving no residue (Ph. Fran.) Impurities : lead salt, lime, lime sulphate, sodium chloride, oxalic acid, butyric acid. AdulttTutions : ex- cess of water, dextrin, glucose synii), honey (Ph. Fran.) The suljiliunc acid Ust is doubtless severe enough if the directions of the U. iS. Ph. be followed with omission of the gentle warnuug, as sufhcient eh'\'ation of temperature results from the admixture. The silrer iiiirKfi' test is mucli infliu-nced by the conditions of time and light. If tix-atment with test solution of silver nitrate for half an hour, in the dark, be adiipt- ed, the test is certainly not too severe. The eovihnxtiint test is efficient for the exclusion of carbohydi-ates. Messrs. Patch, Warder, and Goel)el have each lately reported upon the quality of glycerin sold in the United States.' GUARANINE. See Caffeine, p. 77. HOMATROPINE. See Mideiatig Alkaloids. HOMOQUININE. See Cinchona Alkaloids, p. 'J2. HYDRASTINE. CooIL.sNOy = 397 (Mahla, 18(i:;).— The colorless alkaloid of Hydrastis Canadensis, or " golden seal " root, in which it accompanies the yedow alkaloid berlierine. Hydras- tine is als(j a commercial name for medicinal preparations of the yellow alkaloid berlierine, from Hydrastis.' Periins obtained ' Proc. Am. Pliarm. for 18.45: 33, pp. 481, 4S4. 48."i. ' The colorless alkalnid of Hydrastis was luiiinunced as a crystallizable al- kaloidal body, in 1^51, by Purand, of Philadelphia, who proposed the name "hydrastine," bnt was left in doubt bee.-iuse unable to obtain crystallizable salts. The name "hydrastine" had been {jiven to the yellow alkaloid of golden seal by Rafinesque in his " Medical Flora ol' the Uniled Slates," vol. i., 1828. In Europe the yellow alkaloid had bern found in other plants and liamed "jamaicine " by HuTTENsrnMii) in 1824, " xauthopieiite " by t'uE- VALMER anil PEi.LETANin lH2li, aiel "berberine" by I'.lc [iNEii and IIerberuer in 1830, with a. lietter descnpliun by Feeitsian in 1817. The yellow alkaloid was found in Hydrastis by Dimjanu in l^ni, and idenlilled with the yellow al- kaloid of Berberis and other plants by i\UiiLA as late as 1SU2, mid by Periiixs. 1868. Prof Lloyd states (1884) that " there is little indication thai Ihe term hydrastine," as applied to the yellow alkaloid of Hydrastis, "will be sup- to 330 HYDRASTINE. \\ per cent, from the dried root. Lloyd states the yield in manu- f aeture to be J to f per cent. Hydrastine is characterized by its crystalline form when free, and the auiorplious condition of its salts (a), with the reactions it gives as an alkaloid ( times its weight of cold water, to winch sulphuric acid lias been carefully added to slight acid reaction ; after twenty -four hours the li(j^uid is filtered and ammonia in excess added to the filtrate, the pre- cipitate collected on a strainer, dried, and then powdered and ' Proc. Am. Pkarm., 32, 450. ^884: Proc. Am. rharin., 32, 454. 332 HYDRASTINE. extracted with boiling alcohol. On cooling the solution gives crystals of hydrastine, still dark yellow witli impurities, and to be recrystallized from alcohol, repeatedly, until perfectly color- less. f. — (JiKintitative — The free alkaloid crystallizes anhydrous, CoHosX* )j;, and the crystals or the well-washed precipitate by ammonia, when obtained colorless, may be dried at 100° C for weiglit. The gold chloride of hydrastine, by precipitation of the hydrochloride of the alkaloid with auric chloride, and drying at lob" C, gave Prof. Power ' l(i.9::: per cent, of metallic gold. The formula. (C,,.,1L,...N( )q . HCl)2Au( 'Ig = 1 169.2, indicates 16.78 per Cent, of gdld ;ukI ()7.'.»1 per cent, of hydrastine. The platinum chloride, obtained l)y precipitation of the hy- drochloride solution, gave Mahla 16.1 Tj?; of platinum; the for- mula ((_'o.>llo3^'<->6. IlC.'ljoPtC'l^ indicating 16.1;^,'^ of platinum. HYDROQUININE. See Cinchona Alkaloids, p. 91. HYGRINE. See Coca Alkaloids, p. 173. HYOSCYAMINE. See Midriatic Alkaloids. IGASURINE. See Steychnos Alkaloids. INKS. See Tannins. JAPACONITINE. See Aconite Alkaloids, p. 18. KAIRINES. See Cinchona Alkaloids, p. 166. LANTHOPINE. See Opium Alkaloids. LARD. See Fats and Oils, p. 290. LINOLEIC ACID. See p. 249. LINSEED OIL. See p. 284. MADDER RED. See Coloring Matters, p. 189. MAGENTA. See p. 191. '1884: Proc. Am. Pharm., 32, 453. MALIC ACID. 333 MALIC ACID. iLcji^Og = 110. co,,ii.c'ir.,.c'ii()rr. COoII. Aept'clsiiiii-L'. — Distrilditcd widely throiii;li tlie vcj^rtiiblo kiiiu'dom. lu'[i(>rtiMl ulreudy in not less than iitio plants (lliisc- niann's " PtianzenstotTc "). ^[(jst abundant in fruits, l)iit found in other parts of plants.' Usually ohtaine'il from niountaiii-ash berries or from unripe apples. Lexsskx (iSTd) obtained (i CiJv' from liarliei'r\' berries, only l.TiS'?; from mountain-a.sli buri'ii/s. Others report about 2'^ from the latter. It is abundant in to- bacco. It is believeil identical with Minispermie. acid, Solanic acid, Tanna<'etic acid, Euphorbic acid, and perhaps with Ii;asuric acid. It is formed artiticially from aspara^in, from tartaric acid, and from succinic acid. It is not manutactured for use. sialic acid is ulent'/.jied, more cs[iecially, !iy its sublimation products [a), the deportment (if its lead precipitate when warmed and when treated with annnoiiia, and the formation of its cal- cium precipitate by alcohol, also by its reduction of dichromatc with apple-odor [il). It is ai-parnted from citric, tartaric, and oxalic acids bv non-preci})itation in lioiliui;' c;ilcic aipieons solu- tions, or by the alcohol solubility of its ammonium salt ('/;; from fruit juices by systematic treatment {e). IJstl iiutft'il, i;i'aviiiiet- rically, as lead salt (/'), or as calcium salt weii;-lied as sulphate. Methods of preparation are indicated at 'j. a. — ^Inlic acid crystallizes with some difficulty, and from syrupy solution, in tufted needles or in four or six sided prisms, anhy° or ls(i"^ C'., malic acid evolves vapors of maleic and fuinaric acids, which- cryst;dlize in the retort and receiver. The funiaricacid forms slowly at l.'iH'' ( '., and mostly crystallizes in the retort in broad, colorless rhoniliic. or hexaL;'oiial prisms, which vaporize without iiieltiiiii' at about i!()()'" ('., to condense in needles, and are soluble in 'J.'iH parts of water, easily soluble in alcohol ) : Citrate, Malate. Wash Precipitate (((), digest it in the cold with sodium hydrate solution (or potassium hydrate solution), then dilute a little and filter. Residue (c): Oxalate. JN^early insoluble in acetic acid. Solution {(l) : Tartrate. Boil some time. A precipitate indi- cates tartrate. Test by reducing power, with dichromate, silver salt, or peruuiuganate, and by Fentou's color test. To Filtrate {h) — which must have excess of calcium chloride — add 3 times its measure of alcohol. If a pre- cipitate occurs, tilter. Precipitate (e) : Citrate, Malate (nearly complete). Filtrate (/") : (May contain benzoic, acetic, formic acids, etc.) Wash Precipitate {/') with alcohol ; dissolve on the filter with dilute hydrochloric acid. To the iiltrate add ammo- nium hydrate to sligjit alkaline reaction, and boil for some time. If a precipitate occurs filter, hot (Filtrate h). Precipitate (g) : Citrate. Confirm by dissolving again with hy- drochloric acid, neutralizing with ammonia, and boiling, to obtain a precipitate. Other tests may be applied. Filtrate (A) : ilalate. (May contain succinate.) Try for malic acid by precipitating with strong alcolioL Test a precipi- tate, so obtained, l)y reduction of diclu'onuite, by lead pre- cipitate, and other tests. To separate from succinic add strong nitric acid and evaporate to (h'yness, when there will be oxalic acid instead of malic, the succinic acid un- changed Test for oxalic by calcium salt. Malic acid may be separated from Tannic acid by digesting the solution a halfdiour with well- washed rasped hide, and filter- ing out the tannate. The filtrate may be concentrated and treat- ' Except final tests, arranged from Fresenius' "Qualitative Analysis," S. \V. ,Ji)linson's edition of 1875, p. 304. MECONIC ACID. 337 ed with lead acetate, to be tested for malic acid. Or both acids may be precipitated by chloride of calcium, with a slight excess of aiiimuiiki and alcohol, and tiie malate then washed out of the precipitate with water.' Also, tannic and gallic acid may be re- moved by acetic ethci-. For determining the presence of malic acid in Fruit Juices, the expressed juice or water extract is iirst precipitated by lead acetate solution, when the washed precipitate may be treated as directed under p'in<\ UijuKciiainhie, and JJyosciiie {})i2ii\t\(i belladonnine). The alkaloids of the nndriatic group, like the A(;onite group of alkal(.)ids and like (^>caine, are to be treatefl with a clear understanding of the fundamental fact comuKjn t(j these grou|)s, that thfy arexdjionijidhlr hoillis — a fact that sheds most welcome light upon the long standing difHculty of preserving these alkaloids intact during operations for thcii- 'Some authorities classify the midriatic plants uniltT the order ol Scrophulariaoeae. 340 MIDRIA TIC ALKALOIDS. separation.' Tlie tropeine alkaloids, including artificial tropines like Iloinatrojiine, liave strongly marked cliemical characteris- tics — including a quite direct relationship to benzene, as shown by '' the odor test " ; and an exceptionally strong alkalinity, as shown by phenol-phthalein. The soui'ces of the three natural tropeine isomers already known are as follows : Medicinnl drug, and commer- cial alkaloid. Plant. True alkaloids (Ladenbues). Belladonna, root, leaf. " Atropine." " Heavy atropine ' of llerck. " Heavy daturine." Atropa Eella- donna. Atropine (larger part). Hyoscyamine. In root, belladonnine. Total, 0..'! to 0.5 per cent. Root -J more than leaves. Hyoscyanins, leaf, seed. " Hyoscyaniine." "Light atropine" of Merck. Hyoscyamus niger. H. albus. Hyoscyamine. Ilyosciue. Total, 0,1 to 0.5^ Straninionium, leaf, seed. " Daturine." "Light daturine." Datura Stram- monium. Hyoscyamine. Atropine (a little). Total, U.M to 0.3$^ Duboisia. " Duboisine." Duboisia niio- poroides. Hyoscyamine. ' Kraut, 186:3-65: Ann. C'hem. Phar., 128, 280; 133, 87; Watts's Did., 5, 895. Ladenburg, in part with Meyer, Smith, and others, 1879 to 1884. A summary to 1883 in Liebig's Annalen, 217, 74; Jour. Ghent. iSoc, 1883, Abs., 670; Proc. Am. Pharm., 32, 316; Am. Jorir. Phar., 55, 463. Jour. Chem. 80c., 1884, Abb., 761. Tropine, the common base of the Atropine group of alkaloids, is a deriva- tive of pyridine. Pyridine, CbHsN, is the primary nieinber of the pyridine se- ries, CnHjn-sN, and the type of tlie quinoline series, CnH.j„_,iN. Both series have great interest in the chemistry of natural alkaloids, many of which are found to be clearly placed in the aromatic group. There is a great deal of evidence now making it probable, that alkaloids generally are liydrogenized derivatives of pyridine. See Vixaier Ciachon a Alkaloids, Gonslituiion of, and Quinoline. (Ladenburg, 1884, 1885; A. W. Hofmann. 1884, 1885; Hantzsch, 1884; KiJNiGS, 1884. Review in Am. Chem. Jour., 1883 85: 4, 64. 157; S, 60, 72; 7, 200. Ladenburg ()laces the rational formula of tropine, as C6H7(C2H, . 0H)N(CH3) = C8Hi6N0. That is, in a latino chloride of hyoscine forms small octahedral crystals, soluble in water and in alcohol (of hyoscyamine, triclinic crystals ; of atropine, raonoclinic crys- tals). Iodine solution in potassium iodide gives a dark-colored, oily product. Potassium ferrocyanide gives a white, amor- phous precipitate. The precipitate with Mayer's solution is yellowish ; with mercuric chloride, amorphous, sometimes oily liquid. Treated with barium hydrate for tropine, as given under Atropine, r/, the isomer named pseudotropine is obtained. This crystallizes in rhombohedrons, melts at 106° C, and boils at 241° C. (tropine melts at 62° C), dissolves readily in water and in chloroform, sparingly in ether. The aurocliloride melts at 198° C. The tropic acid of hyoscine is identical with that of hyoscyamine and atropine. Ladenbueg separates hyoscine from hyoscyamine by forma- tion of the aurochloride, which is crystallized several times for removal of the more soluble hyoscyamine salt (atropine auro- chloj'ide, if present, being removed at tirst as a nearly insoluble precipitate). The crystals obtained are decomposed with hj'dro- gen sulphide, the filtrate made alkaline with potassium carbonate and shaken with chloroform, and the resulting chloroform solu- tion evaporated to give a residue of the hyoscine. HoMATEOPiNE. — Cigllo^NOg. Phenyl glycollic tropeine. One of a group of artificial alkaloids called tropeiiies, and produced by 'H. C. Wood, 1885: Tlie.rapeutic Gazette, 9, 1, 594, 760. ' By one-fifth the quantity (!) Ejimeet. See also UiRsonBEao, 1881. 344 MIDRIATIC ALKALOIDS. Ladenbueg (1880) by uniting tropine, the common base of natu. ral atropine and hyoscyaniine, with various acidulous and other radicals, p. 339. Homatropine is formed by the union of tro- pine, CgH^gNO, with mandalic acid, CgHgOg, a molecule of water being separated. Mandalic acid is formed from amygdalin by digestion with hydrochloric acid, and in other ways, and has the structure CgHg . CHOH . COoH, phenyl-glycollic acid. When mandalate of tropine is digested with hydrochloric' acid, the ele- ments of water are withdrawn and homatropine is produced. CgHisNO.CgHgOg^CieHoiNOa + HoO. Since about 1S82 homatropine hydrobromide has been used medicinally. It is an active midriatic ; its efEects do not continue as long as those of atropine, and in the same doses it is less poisonous. Homatropine is crystallizable in prisms from a solution in absolute ether ; has a melting point of about 98° C. ; is hygro- scopic and very deliquescent ; and it is ordinarily obtained only in the state of a thick liquid. It dissolves some in water, but is not freely soluble in water. It is freely soluble in ether and in chloroform. The nydrobromide, CjgH2;i]Sr03 . HBr, crystallizes in flat, rhombic prisms forming wart-like aggregations, perma- nent in the air.' It is soluble in ten parts of water, the solution not readily suffering change. The hydrochloride is very soluble in water, and is crystallizable. The sulphate crystallizes in silky needles. With solutions of homatropine salts potassium mercuric iodide gives a white, curdy precipitate ; gold chloride, a pre- cipitate, C;igII„]^]Sr03 . HCl . AuClg , at iirst of oily consistence, soon crystallizing in prismatic forms ; picric acid, a precipitate soon becoming crystalline. Platinic chloride gives a precipitate only in concentrated solutions, but line crystals of the double salt are formed (with the hydrochloride). Atropine. — C^yHogNOg ^ 289. Tropate of tropine, and pro- bably 05117(02X140 . 00 . OHOeHg.CHa .OH)N0Il3 (Ladenbueg). For sources and chemical structure see p. 339. Forms the larger part of pharniacopoeial "atropine"; a smaller portion of the "daturine" or "atropine" obtained from strammonium; and an isomer of the alkaloids hyoscyamine and hyoscine. Atropine and its isomers (hyoscyamine, hyoscine) are identified as midriatics by the organoleptic test (h, d) ; as tropine tropates by Vitali's test, the crystallizable bromine precipitate, the phenol- ' F. B. Power, 1882: a summary upon homatropine. Am. Jour. Phar., 54, 145. A TROPINE. 345 phthalein reaction, the test with mercuric chloride, and (if in suf- ficient quantity) by the odor tests (c[). Atropine and its 'iKomerK are distinguished from each other by the precipitation with trold chloride, and by differences in reactions with mercuric rhloride, platinum chloride, and picric acid, that with gold chloride being serviceable for separation. Ilyoscyamine from atropine b}' their melting points. Atropine and its isomers are Heparntid from crude drugs, extracts, plasters, animal tissues, the urine, etc, by general and special methods given under e ; and are estimated in quantity, by gravimetric, volumetric, or ])hysiological method, as laid down under f. Tests for impurities, g. a — Colorless or white, lustrous acicular crystals, or a crystal- line or nearly amorphous powder. In commerce sometimes yel- lowish. By exposure to air it acquires at length a vellowish or even violet tint. Melts at 114° C. (237.2° F.) (Ladenbueg, ISSl) (U. 8. Ph.) At 116°-115.5°C. (23'.t°-240° F.) (E. Schmidt, 18S0). The medicinal atropine heated alone on a bath of glyce- rine begins to melt at aliout 104° C. and is entirely melted at 113° C. (Squibb, 1885). The artificial alkaloid melts at 113.5° C. (Ladenbueg, 1883). At 123° C. gives a faint mist of micro- scopic sublimate, not crystalline (Blyth). Vaporizes at aliout 140° C, giving white fumes and an oily sublimate.' A^aporizes slightly with boiling water, and even with boiling alcohol (Dra- gendorff). When dry does not lose weight at 100° ( ' ( Dunstan and Ransom, 1886). Upon ignition it is easily dissipated, with- out residue. h. — Without odor, it has a disagreeably bitter and acrid taste. The largest medicinal dose is ul)out tj"^ grain (Ph. Germ.), and it is an active deliriant pois(jn. — Solutions for a])plication to the eye should never exceed the strength of one per cent., and for the test of midriasis should be far more dilute than this. The cat is a favorable subject for the test. A solution in l.'JOdOO parts of water, applied to one eye of a cat, suffices for dilatation (Dkagendoeff). With frogs a solution of 1 to 2.50 obtains dila- tation, commencing in about live minutes (v. Geaefe). Dr. E. E. Squibb (1885 ') reports the following results upon the huu\an eye, on applying to one eye of each person one drop of a soln- ' As to the form of the crystals, formed under the microscope, see Helwiq. 1864; A. Percy Smith, 1886. '' Uphemeris, 2, 855. See also "Blyth on Poisons," 1885, New York, p. 346 MIDRIATIC ALKALOIDS. tion of atropine sulphate diluted nearly in the proportions here stated : Dilution. Individuals under trial. Commencing dilatation. 2280 parts Several. Several. Two. Two. Two. Five. 15 to 18 minutes. 4560 " 30 minutes. 9120 " About 40 minutes. 18240 " 45600' " 50 and 32 minutes. 45 minutes each. 91200 " In two, no effect; in three, effect in about 1 hour. The same persons were not used in all experiments, and eighteen persons in all were employed. The sulphate of atro- pine was " about the best obtainable in the market." A sample of crude atropine fresh from an assay of belladonna leaf gave earlier dilatations, and in the last trial, by dilution to 90800 parts, gave dilatation in 45 and 50 minutes. The investigator esti- mated that an effect in 50 minutes was obtained by action of about 0.000000427 gramme of the alkaloid. — Atropine is ex- creted by the urine to some extent, being found in that fluid after administration. In frogs the constitutional effects of atropine are peculiar, including first paralysis, and, after a day or later, tetanic spasms. c. — Atropine is soluble in 600 parts of water at 15° C. (59° F.), or in 35 parts of boiling water ; soluble in glycerine, and freely soluble in alcohol, chloroform (3 parts), ether (60 parts), amyl alcohol, and benzene (42 parts), scarcely soluble in petroleum benzin or carbon disulphide. Fixed oils dissolve it. Aqueous solutions are not very stable. — It has a decided alkaline reaction, exhibited not only with litmus-paper in common with most alka- loids, but with phenol-phthalein, a difference of atropine and its isomers from other alkaloids (Flijckigee, 1886). Its special alkalinity is also shown by its reaction with mercuric chloride (see d). — Its salts with the stronger acids are freely soluble in ' Graefe gives 1 to 38000 as the dilution for moderate dilatation commeno ing in f to 1 hour. A TROPINE. 347 water or alcohol ; not soluble in chloroform or ether. At 50° to 60° C. both benzene and amyl alcohol extract a little atropine from acidulous solution (Dkagendokff). The sulphate crystal- lizes anhydrous, (Ci-,n„3N03)2lIoS04. The salicylate is of neu- tral reaction, not crvstallizable, deliquescent, not stable in solu- tion. Dr. Squibb (1885) advises the preservation of aqueous so- lutions of atropine sulphate by salicylic acid, a cold saturated solution of which is taken for one half of the solvent. d. — In evidence of the presence of atropine, the physiological test for the pupil-dilating alkaloids, chiefly atropine and its iso- mers (p. 340), deserves to be named first. Of bodies other than the solanaceous alkaloids it is to be observed that cocaine, digi- talis and its active principles, and conine dilate the pupil of the eye. Aconitine has a variable effect of dilatation. Nicotine is stated to first dilate and then contract the pupil. Selmi (1877- 1879) found certain ptomaines to dilate the pupil. The visual effect of the solanacese seems to have been imperfectly known prior to the last quarter of the eighteenth century.' The limits are given under h. Dilatation from a solution not stronger than 1 in 500 parts causes little inconvenience to tlie human eye. The eye of the cat is preferable. In testing the separated product of an analysis, an aqueous solution is obtained of the free alkaloid or it* salt (sulphate), neutral or only very feeldy alkaline in reac- tion, and not strongly saline with any metallic salts, and not al- coholic. A drop or two is let fall into one of the eyes, the time iKited, and from time to time the width of the one pupil is com- pared with that of the other. Vitdli's test is made as follows : The dry residue is treated with a little fuming nitric acid, then dried on the water-bath, and when cold touched with a drop of solution of potassium hydrate in absolute alcohol, when, in evidence of atropine (or one of its isomers), a violet color will appear, slowly changing to a dark red. Strychnine gives a red, bruciiie a greenish color. The violet color is distinctive for atropine among all important alka- loids, and reaches the limit of 0.000()01 gram of the alkaloid (D. ViTALi, 1880). Arnold (1882) in this test uses, instead of fum- ing nitric acid, first a drop of sulphuric acid rubbed, cold, to moisten the residue, and then a solid particle of sodium nitrite. With atropine the violet does not appear till the alcoholic potash is applied (strychnine, orange-red). Colors appearing before the ' See an interesting historical paper by Kobeht, 1886: Tlierapeutic Qazdte, 10 445. 348 MIDRIATIC ALKALOIDS. alcoholic potash is added (narceine, morphine, narcotine) render the test inapplicable. Phosphomolybdate of sodium gives a yellow precipitate, visible in dilution to 4000 parts (Deagendoeff), dissolving in ammonia with a blue color.— Iodine in potassium iodide solu- tion, better applied to the hydrochloride solution, gives a precipi- tate of the color of the iodine solution, oily at first and afterward crystalline (Ladenburg), distinct in solution of 8000 parts of water and visible in solution of 50000 parts (Jorgensen), more complete than precipitation by phosphomolybdate (Dunstan and Kansom), dissolved by boiling alcohol, from which solvent it crystallizes, blue-green, as pentahydriodide. For separation of the alkaloid from this precipitate see e. — Bromine dissolved to saturation in hydrobromic acid solution gives a yellow precipi- tate, at first amorphous, obtained in a solution of the alkaloid in 10000 parts of water (Woemley '), not dissolved by acids or fixed alkalies. The amorphous precipitation is common to most alka- loids, but the precipitate of atropine and its isomers is character- istic in this (Wormley) that it soon becomes crystalline, and under a magnifying power of 75 to 125 diameters presents distinctive forms of lanceolate leaf-like crystals, which gradually group to- gether like the petals of a flower. These crystals may be obtained from spontaneous evaporation of one grain of a solution diluted to 25000 parts. Imperfect crystallization gives only irregular needles and granules. Repeated trials are made by dissolving in a drop of water and crystallizing anew. Phenol-phthaleln as an indicator applied to the free alkaloid, as to the chloroformic or ethereal residue, gives the scarlet color in evidence of alkalinity, this reaction being, according to Prof. Fluckiger,^ common to atropine and its isomers and liomatro- pine, and a distinction from all alkaloids in general use. Mercuric chloride in a 5 per cent, solution in 50 per cent, alcohol, avoiding an excess, gives a red precipitate containing mercuric oxide (Geeeaed, 1884: ; Schweissingee, 1SS5 ; Flijcki- GEE, 1886). On standing tabular crystals of atropine mercuric chloride are obtained. With hyoscyamine the precipitate appears only after warming (Schweissinger). With this reagent most alkaloids give white precipitates ; morphine and codeine, yellow ones. Of course inorganic bodies of alkaline reaction must be absent, and the alkaloid must be free. — Potassium mercuric iodide, or Mayer's solution, gives a whitish, curdy precipitate, ' " Microchemistry of Poisons," 2d ed., 1885, 641. '1886: Phar. Jour. Trans. [3] 15, 601; Am. Jour. Phar., 58, 129. A TROPINE. 349 hardly visible in solution diluted to 4000 parts (Deagendoeff).— Potassium bismuthic iodide, a precipitate visible in solution diluted to 25000 parts (Theesii, 1880). Gold chloride, a lustre- less precipitate, discernible in solution diluted to 20000 parts, melting at 135° C. (Ladenbukg). C17II34NO3. AUCI4. The liy- oscyaniine precipitate, with gold chloride, has a golden lustre and melts at 159° C. (Ladenbl'eg). Platinum chloride (wiLh hydro- chloric acid) precipitates only very concentrated solutions of atropine ; the crystals of chloroplatinate are nionoclinic and melt at 2o7° C. (hyoscyamine chloroplatinate crystals are triclinic) (Ladenbueg). Picric acid (Hagee) with the "English atro- pine " ([). oil) gave an amorphous turbidity, wliicli, after heating to dissolve it, crystallizes in rectangular plates on cooling. The *' German atropine," treated in the same way, gave the rectangu- lar plates at once. Tannic acid precipitates neutral and con- centrated solutions of atropine. — The dilute caustic alkalies, and sodium and potassium normal carbonates, precipitate, from con- centrated solutions of atropine, a part of the alkaloid, soluble in an excess of a caustic alkali. On heating the fixed alkali solu- tions ammonia is finally evolved by decomposition of the atro- pine. Ammonium carbonate and fixed alkali biearbonates give no precipitates. Concentrated sulphuric acid gives no color. Atropine, in common with its isomers, is easily sapon'ified, or resolved by alkalies into its teopine and teopic acid. (See un- der Midriatic Alkaloids.) The aqueous solution of alkaloid is digested with barium hydrate at 60° to 80° C. ; then carbon dioxide is passed in and the barium carbonate filtered out ; the :filtrate is acidified with hydrochloric acid and shaken with ether, in two portions ; the separated ether is allowed to evaporate spontaneously, when tropic acid is obtained in the residue. The aqneous solution left after removing the ether is now treated with potassium hydrate solution to an alkaline reaction, and the liquid again extracted with ether, which is allowed tti separate after shaking, drawn off, and evaporated in a warm place. The residue will contain the tropine. Instead of digestion with barium hydrate, digestion with hydrochloric acid may be enipluyed. Tropic acid melts at 117° C. Heated with dilute solution of permanganate it gi\'es odor of bitter-almond oil, and on further treatment benzoic acid is formed. Tropic acid is easily changed, by loss of Hr,0, to atropic acid, CgllgO^, isomeric with cinnamic acid. Tropine crystallizes from anhydrous ether in the rhond)ii' system, and melts at (J2° C. It is hygroscopic, in ordinary resi- dues assumes an oily consistence, is freely soluble in water, in alcohol, and in ether, lias a strong alkaline reaction, gives an odor 350 MIDRIATIC ALKALOIDS. when lieated, and forms definite salts with acids. The chloro- platinate crystallizes with orange-red color, dissolves in water, not in alcohol. J'he odor test, by production of benzoic or salicylic aldehyde, is made, in several ways, by concentrated sulphuric acid alone, or by this followed by dichromate or other oxidizing agent, and is directed as follows in the Ph. Germ. : " 0.001 gram [at the least] of the atropine sulphate, in a small test-tube, is heated until white vapor appears, then 1.6 grams of sulphuric acid is added, and heated until it commences to brown. Now on adding 2 grams of water an agreeable odor is perceived, and by further addition of a crystal of permanganate of potassium the odor of bitter-almond oil is obtained." This reaction, by whatever reagents, is not a delicate one, and often fails, but it is characteristic in comparison of ordinary alkaloids. e. — Separations. — Aqueous solutions of atropine, in concen- tration by heat and in standing, are liable to suifer very sliglit waste of the alkaloid by its decomposition, but this waste is less for salts with stable acids than it is for the free alkaloid, and in ordinary evaporations is prevented by adding enough dilute sul- phuric acid to neutralize or barely to acidulate the liquid. — Acidulous solutions of atropine can be washed by petroleum benzin without loss of the alkaloid, and washed by chloroform or ether with only so much loss as results from the slight misci- bility of the water with these solvents. Chloroform or ether, preferably the former, or, if separations require, benzene or amyl alcohol, by agitation (in I'epeated portions) with aqueous solu- tions made alkaline, will extract the alkaloid almost without waste The certainty of complete separation is assured bj' a negative result in testing the aqueous solution with phosphomo- lybdate, or iodine in potassium iodide, or a residue on evaporat- ing a portion by Vitali's method. Also, it is important to remem- ber that when an acidulous solution is made alkaline a salt is formed, as ammonium sulphate, and such salt will be carried into chloroform or ether or amyl alcohol, and on evaporation of the solvent a crystalline residue of the salt will be obtained. If the salt be ammonium or other alkali sulphate, the atropine is safely separated from the residue by solution in absolute alcohol. Again, water acidulated with sulphuric or hydrochloric acid, agitated with a solution of free atropine in chloroform or other above-named solvent, gradually transfers the alkaloid to the aqueous solution. The remaining chloroformic or ethereal liquid is tested, as to the progress of the separation, by subjecting a ATROPINE, 351 residue from a small portion to Vitali's test. An aqueous solution so obtained may be precipitated by iodine in potassium iodide solution for estimation of the alkaloid, as directed on p. 354. In separating the aqueous layer from an iinder-layer of chlo- roform, or from an over-layer of ether or benzene, a "separator" made for the purpose is, on some accounts, the most convenient vessel, but the use of a large, strong test-tube, or test-glass on foot, with the vrashbottle fittings for siphon-decantation, is very satisfactory. These forms of apparatus are figured and described under Alivaioids, pp. 35, 36. For sejjarations from belladonna root and leaves Dunstan and Ransom (1884, 1885)' direct as follows : " Twenty grams of the dry and finely powdered root are exhausted by hot percola^ tion with a mixture of equal parts by volume of chloroform and absolute alcohol; and if an extraction apparatus is used about 60 c.c. of the mixture is required. The percolate is agitated with two successive 25 c.c. of distilled water [acidulation having been found unnecessary], which [the watery layers] are separated in the usual way. These are mixed and well agitated with chloro- form to remove the last traces of mechanically adherent coloring matter. The cliloroform is separated, the aqueous liquid rendered alkaline with ammonia and agitated with two successive 25 c.c. of chloroform, which are separated, mixed and agitated with a small quantity of water (rendered faintly alkaline with ammonia) to remove adherent aqueous liquid. The chloroform is then evaporated and the residue dried over a water-bath until tlie weight is constant, which usually occupies a little less than an hour." The alkaloid is obtained in white, silky crystals, for weight, and by trial found pure alkaloid. For the leaves " 20 grams, dried and finely powdered, are well packed in an extrac- tion apparatus, and exhausted with about 100 c.c. of absolute alcohol. The alcoholic liquid is diluted with about an equal volume of water made slightly acid with hydrochloric acid. The chlorophyl, fat, etc., are then removed from the slightly warmed liquid by repeatedly extracting it with chloroform until nothing further is removed by the solvent. The aqueous liquid is made alkaline with ammonia, and the alkaloids extracted by chloi'o- form, by evaporating which a residue of pure alkaloid is olituined, and dried by heating it at 100° C. until a constant weight is attained." 'From the Root: Phar. Jour. Trans. [3] 14, 023: Am. Jour. P/iav., 56, 279. From the Leaves and the Kxtriict: Phar. jour. Tran.t. [3] 16, 2:i7, 2:i8; Am. Jour. Phar., 57,583, 584. Aaring crystals under the mici'osi/t;illizable, in four-sided prisms or in needles. Of bitter taste, styptic after taste, and purely hypnotic effect. Sparingly soluble in hot water or cold alcohol, soluble in hot alcohol ; nearly insoluble in ether, or benzene, or petroleum benzin, or (Woemley) in chloroform ; moderately soluble in amyl alcohol, not from acid solutions. It is of neutral re- action, but unites with acids, forming crystallizable salts. Colored by sulphuric acid, brown or black to yellow or red ; by nitric acid, yellow ; by Froehde's reagent, yellow-brown to blue. (6) Pseudiiniorjfhitie, C-^^-jW-^^O^. Pelletiee and Thiboumeey, lSo5. Yield, not ovei- 0.02 per cent. Lustrous crystals. Tasteless, and of neutral reuction. Insoluble in water, alco- hol, ether, chloroform, dilute acids, or alkali carbonates; soluble in caustic alkalies or lime solution. Colored by sul- phuric acid an olive green ; by nitric acid, orange-red. Forms acidulous crystallizable salts, difficultly soluble in water or alcohol. Hesse infers that this is the same as Oxy- morphine, formed ])y action of nitrites on morphine, as stated under Morphine, d. (X) Pnjxiverine, CniHoiNO^. Meeck, 1848. Yield, sometimes as liigii as 1 per cent. Ci'vstalline, in white needles or prisms. In action resembles morphine, but is much feebler. It is slightly soluble in cold alcohol and in ether, freely in hot alcohol, moderately soluble in amyl alcohol, in benzene, and in petroleum benzin, soluble in chloroform both from alkaline and from acid solutions. Does not neutralize even acetic acid. Its salts are very difficultly soluble in water ; its sulphate dissolves in sulphuric acid, but is precipitated on adding water. Colored by concentrated sulphuric aeihine Hitlts. — Moi'jthiae >hlne hi/drnchlofide is sohil)le in 24 pai'ts of water at 15. r!j;iiiiic acids of aromatic composi- tion, including tlio tannins, phcimls, salicylic acid, etc., as enu- merated under Phenol, (? ' Accdi-ding to Siolmi (1ST(!) certain cadaver alkaloids give the liliie color to ferric salts, as well as reduce iodic acid. But these cadaveric alkaloids did not give the violet color oKtaiued by morphine on treatment with a solution of lead dioxide in glacial acetic acid, evaporating at a gentle lieat. The general (pialitative I'ca-gciits for alkaloids all respond to morphine. Phosphomolybdate gives a very nearly complete precipitate of a yellowish-white color, disst)lving in aiiimunia with a blue color. Potassium mercuric iodide, or Mayer's solution, gives a less perfect precipitate, not appearing at all in solutions of 1 to -iOOO. The precipitate approximates to the com- position (Ci-.IIj^9\()3lII)^(IIgIo)3.'' Iodine in iodide of potas- sium solution gives a reddish-brown precipitate, immediately visible in one drop of a solution of the alkaloid in 10000 parts of water (Wokmley) ; under the microscope in a 1 to 1((OUOO solution (Selmi, 1S76). On standing, reddish-brown crystals form. The precipitate dissolves in alcohol, in alkalies, slowly in acetic acid. Its distinction, under the microscope, from other opium alkaloids, is given by Selmi, ISTC,. Potassium iodide gives a formation of needle-shaped crystals, somewhat character- istic, obtained only in C]uite concenti-ated solutions. — Tannic acid and picric acid give precipitates in solutions not very dilute. — Alkali carbonates and bicarbonatcs precipitate morphine, not soluble in excess of the precipitant. Alkali hydrates give a crystalline precipitate, dissolved by excess of fixed alkalies, and Ijy lime solution, spaiangly soluble in excess of ammonia. (Jrystals of free morplune, obtained by precipitation with a little excess of ammoiua, or by spontaneous evaporation of a dilute alcoholic or warm aqueous solution, examined under the microscope (ui comparison with known morphine under like treatment), give valuable confirmatory evidence of the identity of the alkaloid (p. 363). e. — St^pardtioiis. — Aqueous solutions of morphine are con- centrated on the water-l)ath without marked loss, but if the concentration require long time, or if the sohitiou be complex, in a quantitative separation, it is Itetter to ex'aporate under dimin- ished pressure at temperature not above (in- to 75° C — From • CHASTAiXd (1881) claims, from the chemical proportions in which mor- phine unites with fixed alkalies, and other considerations, that this alkaloid is in fact a phenol. 2 The author, 1880: Am. Cltem. Jour., 2, 294. 370 OPIUM ALKALOIDS. substances insoluble in acidified water or alcohol these solvents remove morphine in its salts, and liot alcohol may be used to dis- solve out the free alkaloid. Of solvents not miscible with water, amyl alcohol is the most satisfactory for morphine. The acidified aqueous solution may be purified, or freed from other alkaloids, by shaking out with benzene, or chloroform, or ether, and finally with amyl alcohol itself. Then the liquid is made alkaline by adding ammonia, and exhausted of morphine by I'epeated por- tions of amyl alcohol, or by a continuous liquid-extraction appa- ratus supplied with this solvent. It is to be remembered that amyl alcohol carries with it a little of the aqueous solution, so that the amyl alcohol solution requires water-washing, and a little waste occurs. In separation from the tissues and contents of the stomach, or other matters, in analysis for poisons,^ the solids are finely divided, in a good-sized evaporatiug-dish, by playing upon the material with a pair of bright, sharp shears. The divided ma- terial may then be treated as directed under Atropine, p. 354, substituting amyl alcoholior chloroform as a solvent of morphine. Tartaric acid may be used for acidulation instead of sulphuric, to favor the rejection of ptomaines (Guaeeschi and Mosso, 1883). If it be analysis for opium constituents, it is to be understood that JSTarcotine is dissolved spai'ingly by amyl alcohol applied to acidulous solutions, also sparingly dissolved by benzene applied to alkaline solutions, morphine remaining imdissolved in both these cases. Unless morphine be found in more than traces, narcotine is not likely to be recovered with identiiication. Evidence of opium, in distinction from morphine alone, is more confidently sought througli tests for Mceonic (d'id. This acid may be separated from the aqueous liquid, in the course for morphine, if acetic acid be added instead of tartaric acid, for acidulation. The filtered aqueous liquid is treated with lead acetate solution, just sufficient to complete a precipitate formed, and filtered. The filtral,e is treated with enough hydrogen sulphide gas to throw down all the lead, then filtered, and the filtrate treated in the course of analysis for the morphine The precipitate first formed on adding the lead acetate is washed on the filter M-ith a little water, carried through the filter-point with a thin jet of water, the lead meeonate decomposed by hydrogen sulphide gas, the mixture filtered, the filtrate evaporated, the 'Toxicology: Taylor, on Poisons; Blyth's Poisons; Wharton and Stille, vol. 3, 1884; DragendorfE's " Brmittelung von (TiEten" and " Organisoher Gifte"; Worrnley's " Miorochemistry of Poisons,'' 3d edition, 1885. Struve, 1873; ZeitacK a'nal. Chem., 12, 168. MORPHINE. 371 residue taken up with strong alcohol, this solution filtered and evaporated, the residue taken up with warm water, and tested, with ferric chloride and other reagents, for Meconic acid (which see). Tlie residue from the careful final evaporation of the anivl alcohol solution of morphine — which may be divided in several dishes for the tests and for weight as directed in analysis for atropine — is examined for its deportment in tests by (1) sulphuric and nitric acids, (2) sulphuric and niolybdic acids, (3) ferric chloride, (4) iodic acid, and (5) with phosphomolybdate, as direct- ed for each under (/. Also (6) a drop of the warm aqueous, or dilute alcoholic, solution is allowed to evaporate very slowly, under the microscope, for crystals of free moi-phine, to be recog- nized as stated under a. Other tests may be added. The amyl alcohol used should be examined by evaporating a quantity as large as that used in the analysis, and if any fixed residue be obtained, or if a solution of a supposed residue in acidulated water give reactions with general reagents for alka- loids, then the portion of this solvent to be used must be redis- tilled, after adding a little tai-taric acid. To decide any question as to results, a control analysis should be carried in a parallel operaticiii upon tissue material as nearly as po8sil)le the same as that under examination for poisons. If the tissue material taken be very trouldesome, or if tlie operator prefer, the first s(]lution from the tissues may be an alcoholic acidulous st)lution, and the residue from the evaporation of this solution may be taken up by water (and a very little acid). If acetic acid be used, care must be taken that acid reaction with litmus be main- tained. It is better that the temperature of evaporations lie kept belii\\' 8(J° C, and that coneentratiuiis be hastened by a I'e- duced air-pressure. The recovery of morphine from the body in cases of fatal poisoning by it is by no means always possible. There are numenius recorded cases of failure of eompetent chemists to find this alkaloid. In the living body UKjrjihine is ecinstautly undergoing decomposition. In the dead budy it may sufi'cr de- composition at a very slow rate, thougli it has been found after standing fourteen months in putrefactive liquids (Tavlok). It is highly probaide tliat morphine undergoes waste by deeoiii- position during a prolunged analytical separation from tissiu's. On the other hand, when an analysis is ciiinmeiiced innuediately after the introduction of morphine into tissue material, ic can lie recovered with less waste than attenerinients showing that excess of ammonium chloride causes iM'oportional diminution of yield. Tlie truth of this conchision has been confirmed by Messrs. Wrampelmeier and Meinert (1S86, Inc. cit.) From these observations and those of Lloyd {loc. cit.) it appears that morphine and lime exert a mutual sol- vent action on each other, and that other constituents of opium help to dissolve lime. The more lime the more free ammonia. And both free ammonia and remaining anmionium chloride help to dissolve the morphine.' It appears, therefore, that the pro- ' 1885: Am. Druggist, New York, 14, 221. ' " In order to find out whether the morphine is held in solution by the excess of ammonia liberated or by the excess of ammonium chloride, the fol- lowing experiments were made. By calculation it was found tliat, when 0.202 gram of calcium oxide is in solution, 0.399 gram of ammonium chloride is deci)m])osed. Subtracting this from 3 grams, we find that in this case there is an excess of 2.61 grams of ammonium chloride present in tlie assay liquor. This amount of ammonium chloride was then dissolved in 50 c.c. of pure water and 0.500 gram of morphine added, and the solutiim allowed to stand for 12 hours, after which time 0.500 gram of morphine had lost 0.135 gram. The amount of ammonia which would be set free in such assay was also calculated, and a solution of .'iO c.c. of pure waler containing ihat amount of ammonia was found to dissolve, after 12 hours' sl.aiidiiig, 110 gram of mor- phine. Thus it was shown that both ammonium chloride and free ammonia in 38o OPIUM ALKALOIDS. portion of ammouium chloride directed by the Br. Ph. is advis- able. The quantity of free ammonia liberated from the ammo- nium chloride in the filtrate is limited by the slight but vary- ing solubility of the lime. The excess of lime in the primary maceration serves to improve the consistence of the mucila- ginous matters of the opium, favoring solution and filtration. This use of lime in excess, vsfhich tirst holds the alkaloid mor- phine in an alkaline solution, and afterward, in the iiltrate, be- comes exchanged for free ammonia, (2NH4CI -j- Ca(0H)3 = 2NH3 + CaCU + 2II0O), is credited to the plan of Mohe. "Whether liberated by lime from ammonium chloride, or added in water of ammonia (as by the Ph. Germ.), at all events free ammonia is employed in separating morphine from its com- pounds, to crystallize on standing, in all methods of morphio- metric assay so far well established in use. — The crystallization of the alkaloid requires tinje. In the Hager-Jacobsen processes crystallization was promoted, and the crystals purified, by the addition of email quantities of ether and benzene, not too much to be taken into solution in the crystalliziiig liquid. The use of an excess of etlier\ nmch beyond ether-saturation, so as to cause an ether layer to rise above the crystallizing liquid, along with the frequent shaking up of the ether with the aqueous liquid in the closed flask during crystallization, marks an important prac- tical advance in opium assay. This use of ether, introduced about 1881, has been adopted in each of the three pharmaco- posial processes above given, also in the processes on individual authority, as hereafter presented. By this use of immiscible ether in forcible contact by agitation with the aqueous solution,, crystallization is greatly quickened, and purer crystals are ob- tained. The effect of stirring was emphasized in 1877 by Tesche- macher, who says : " The rapid and continuous stirring is most important, as the precipitation of the whole morphine in fine powder is thereby effected, instead of the granular or mammil- fated condition so frequently met with." This eifect on crystal- line precipitates, in numerous analytical operations, is well under- stood at present. The addition of alcohol, in the crj'stallizing liquid, is well understood to cause winter and liner crystals to be obtained, but, unless counteracted with ether or by greater solution exert a distinct solvent action upon the alkaloid. It is therefore probable that by using about 1.000 gram oJ! ammonium chloride instead of 8.000 grams, the amount of morphine held in solution will be greatly re- duced."— Wrampelmeieb and Mbinebt, 1886: Am. Druggist, New York, 15, 203. MORPHINE. 381 copcentration, alcohol in proportion to its (quantity tends to di- minish the yield of crystals. By the processes of the Ph. Germ, and Professor Fllickiger, alcohol, ether, and aH23N07 = 413. (For structure see p. 361.) — Occurs in opium, in very variable proportions, from 1.3^ to 10.9'"c'. Sduie samples of French opium do not contain any re- coverable by ordinary methods. T. and II. Smith found an al- kaloid, aconelline, in the roots of Aciniiturii Ndjidlus, which they tliouglit was identical with narcotine. Xarcotine is characfei'hed by its deportment with pure sul- phuric acid, and with sulphuric and nitric acids (d) ; dixtlii- (ju'ikJiciJ and separated from morphine by its solubility in ether (c), evuu from feebly acidulous solutions. It is estinuiied i:^rsiV\- mctrically or by Mayer's solution (/'). Separation from opium (ej, from morphine, under Morphine (g), \>. 386. a. — C'rvstallizes from alcohol or ether in colorless, transpa- rent, orthorhombic prisms, or in groups of needles, which melt at 17'* parts acetic ether; in 2.7 parts chloroform ; in ;'>()() ]iarts amylic alcohol ; in 22 parts benzene ; slightly soluble in petroleum bcnziii, which 388 OPIUM ALKALOIDS. takes up only a trace from alkaline solutions (Deagendoeff). Chloroform removes it from acid solutions. d. — The alkaline hydrates, carbonates, and acid carbo- nates precipitate narcotiite (white, crystalline, insoluble in ex- cess of precipitant). Iodine in potassium iodide liives a pre- cipitate (brown), potassio-mercuric iodide (white amorphous), potassium sulphocyanate (amorphous). The other alkaloid reagents also precipitate narcotine, the precipitates not being characteristic. C, becomes anhydrous at 121° C It is soluble in less than one part of boiling water, in 20 parts of cold water. h. — Codeine is odorless, slightly bitter, and resembles moi-- pliine in its physiological action. The dose is from 0.5 to 1 (i grain (0"o2 to'0.0(i.5'gram). (■, — Codeine is soluble in so parts cold (15° C.) and 17 parts boiliiii;- water; readily soluble in alcohol, ether, and chlorofoian ; in 7 ]Kirts aniyl alcohol ; in 10 parts lienzene ; almost insolnl)le in petroleum benzin. Chlorotorm extracts it most easily from alka- line solutions. It has an alkaline reaction, an greater demand than that of exact execution of well-worn analytical methods. Certainly the estimation of the elements in a given carbon compound already sepai-ated in purity is a very narrow task wlien compared with that of the determination and separa- tion of the several caihon compounds in a given portion of or- ganic material. The proper place which " elementary analysis " holds in ana- lytical cliemistry, in comparison with that of " proxinuite analy- sis," will appear in a true light if we contrast the one kind of analytical work with the other, when apjilied to common iiior- ganlo materials. Thus, there are at least eight sulphur acids oon- sisting each of sulphur and hydrogen and oxygen, liesides com- pounds of sulphur with hydi'ogen, sulphur with oxygen, sulphur with halogens, and numerous other "inorganic" compt(unds of sulphur. The percentage of sulphur in each of these compounds was long since establislied to within narrow limits of error, and their " ultimate analysis" for sulphur is now required only as an the organization of tlie cell, cliemism can c.xert no other power than that of a "eorrelalire force," acting in such a way as that by which heat enables certain chemical combinations to take place. ORGANIC ANALYSIS. 393 infreqTient resort in indirect metliods of estimatin<^ sulpliur compounds. Qualitative and (jiuintitative aTialjses foi- sulpliu- ric acid and for otlier common conipoiiiids of sul])l'ur are in constant demand, and are niaile witli uontidoice, ahlion<;ii wo liave no i;-eneral analytical scheme for all sidplinr c(jmpounds. Determinations of the presence and proportion of sulphuric acid are not spoken of as o[ierations in "proximate auahsis." Neither is the estimation of acetic acid often referred to as a "proximate organic analysis." The term "proximate" has been carefully ilefined, over and over again, to specify a cer- tain kind of analyses, but in its prhirijxil um by chemists the term seems to have belonged mainly to such analytical undertak- ings as have been (piite remote from realization. With this distant apprehension on the part of chemists it is not strange that laymen siiould forget what the precise difference is tetween " prox- imate '' and " approximate" ileterniiiiations in the laboratory. To determine and to separate chemical compounds as they exist in the material under inquiry, to assort tlie nKtlecules and to ascertain their structure without permitting any changes in them to elude observation, is the end to be reached in analytical chemistry, whether of inorganic or organic substances, whether for cpialitative (^r quantitati\'e statements, an. 92. 394 PHENOL. PHENOL.— CgHgOH = 9i. Hydroxylbenzene.— The first member of a series of Phenols, CnHjn-TOH, a series of mono- hydroxjl benzenes. Phenols liave a structure as though derived from the hydrocarbons, benzene, CgHg ; toluene, CyHg, etc.~by substituting OH for H in the mono hydroxyl benzenes, 20H for 2H in the di-hydroxyl benzenes, etc' Phenol may be obtained by the destructive distillation of resins and many other organic substances. It is formed in the dry distillation of salicylic acid, more readily if lime be added : CgH^ . OH . CO3H = CgHgO + COg . The urine of various ani- mals contains phenol, and it is liable to occur in the urine of man. Certain albuminoid decompositions, or putrefactions, generate phenol. It often appears in the distillates from wood- tar, making an impurity, or less valued constituent, of true wood- tar creosote, which contains phenols of another series. But the phenol in use comes from no other source than the distillation of coal-tar, and bears the name of Carbolic Acid. The making of this article has been an industry since about 1860. Crude car- bolic acid contains phenol with the cresols and some of the xyle- nols of the following list. Best-grade carbolic acid is nearly pure phenol. The article sold as " cresylic acid," of variable composition, contains cresols and may include xylenols. Melting.'^ Boiling.^ Phenol, Celig. OH = CgHeO 42° C. 184° C. Cresols, CgH^ . Clig . OH = O^HgO Orthocresol, 1 : 2 31° 186° Metacresol, 1 : 3 liquid 194°-200° Paracresol, 1 : 4 36° 198° Xylenols, CgHg . CH3 . CH3 . OH = — C'sHiqO Orthoxylenol, 1:2:4 61° 225° Metaxylenol, 1:3:4 liquid 211° Metaxylenol, 1:3:2 74° 212° Paraxylenol, 1:4:2 75° 213° 'Kekdlb, 1865: "Organ. Chem.," iii. (1882), 1, 12; "Substitution Pro- ducts," 25. " Watts's Dictionary," Tii. 924 (Armstrong), 132. Ladenburg's " Handworterbuch." Remsen's " Organic Chemistry," 269, 283. ' The melting and boiling points of the isomeric cresols and xylenols have been ascertained, mainly, from the artificial compounds. The isomers have not been separated in purity from coal-tar distillates. 1 1 is not known to what extent xylenols and the several cresols occur in crude carbolic acids and in PHENOL. 395 In the distillation of coal-tar the distillate is received in frac- tions limited usually by boiling points, sometimes by volume- quantities, and generally in part by specific gravities, with regard also to periotls of distillation. The number and limits of the fractious of distillate have varied with the progi-t>s of the in- dustry and with local customs and special purposes.' After va porization of the water and ammonia, under name of the " first runnings " or "crude naphtha,"' a " break " occurs, after which distillation reconnnences at 105° to 110° C. Beginning at this point, the first fraction is almost everywhere named " light oil," and contains the hyc^rocarbons of the lienzene series. Formerly the distillate was generally received as " light oil " until a por- tion ceased to tioat o\\ water (sp. gr. 1.0), when the boiling point is about ^10° C. [Luncje]. At present, in many places where carbolic acid is an object, the "light oil " is cut off at 165°-170° (\ ; and a fraction of " middle oils," for carbolic acid and naph- thalene, is received up to ^^Ci" C. "Light oil," if carried to '210°C., coiitaius a good deal of carbolic acid ; if cut off at 170° C it contains but little. But after a " light oil" is distilled up to i!10°C., a fraction named "carbolic oil" is received, up to 210° ("., as a source of carb(ilic acid. The term "creosote oil" ("heavy oil") is very generally applied to a fraction taken either after "carbolic oil" or "middle oil," and cut off at 2TU^C. C'arbohc acid is not maiie from "creosote oil," ox from any distdlate abheiiiev'i^. i. oO.">). Carbolic acid melts at 35° to 44' C. kPIi. Genu., ls^2|, "at 36° to 42' ( '. (1)6.8° to 107.6° F.). and i)(iils at 181° to ISC'C. (3rM.8° to ;;(;(;.s= F.), the hin'her melting and lower boiling pf)ints being tliot,e of the pure an^l anhydrous acid" (U. S. Ph.,"l8so). Phenol boils at 187° to 188° ('. (Laukkx-i, 1841). A fine spccimmi of carbolic aci). With elevation of tcni[)cratnre a larger proportion of water can be held in solution, the mixture ' 1878: Analyst, 3, 320; Jour. Chem. Soc, 36, 182. 398 PHENOL. becoming turbid when cooled. A permanent liquid state is ob- tained by adding 5 per cent, of water, and this addition, or one of a fluid-ounce of water to a pound of the crystals, is usually adopted in dispensing. Cresols are said to dissolve in about 31 parts of water (?) The alkalies with water dissolve carbolic acid freely, but on neutralizing precipitation occurs, and very little phenol is dissolved in a saturated solution of common salt.' Car- bolic acid is soluble in all proportions of alcohol and of glycerin, and freely soluble in ether, chloroform, benzene, carbon disul- phide, volatile oils, and in fixed oils, water, if present, being partly separated by solvents not miscible with it. Petroleum benzin dissolves but little carbolic acid in the cold. d. — Nitric acid reacts upon the phenols, violently unless diluted, producing yellow to brown nitro-compounds, with escape of brown nitric oxide vapors. With phenol proper it yields successive nitro-phenols, the final product being CgH3(]Sr02)30H, tri-nitrophenic or picric acid. The color is intensified by neutralizing with potash, and the potassium tri- nitrophenate is sparingly soluble in water, less soluble in alcohol, and crystallizes in bright yellow needles. Some analysts add to the liquid to be tested an equal volume of sulphuric acid (not diluted) and then a minute fragment of potassium nitrate. So- lution of mercuric nitrate with a trace of nitrous acid gives the nitric acid reaction visible in dilution of the phenol to 150000 or 200000 parts ; Millon's reagent reveals phenol in dilution to 2000000 parts, in 20 c.c. of solution (0.00001 gram phenol) (Almkn, 1878). Picric Acid has a very bitter taste, colors the skin and fabrics of nitrogenous composition with special intensi- ty, acts as an explosive both of itself and with reducing agents, forms true salts with bases in general, and gives constant jire- cipitates in solutions of the alkaloids. Bromine-water, with solution of carbolic acid, gives a curdy or crystalline, whitish precipitate, tribromophenol, CgHoBrgOH, soluble in excess of the phenol, but permanent upon addition of enough of the reagent, soluble in alcohol, ether, carbon disul- pliide, etc., and in alkalies. The test is very delicate, but in very dilate solutions several hours should be given for the formation of the crystalline precipitate, when one part of phenol in 57100 ' Dry phenol is soluble in an equal volume of 9 per cent, soda solutioQ. With addition of water, up to 7 volumes, the liquid remains clear, but is pre- cipitated by 8 volumes of water. Dry " cresol " is soluble in an equal volume of the 9 per cent, soda, but wiili addition of the soda to 3^ volumes a precipi- tate occurs. Creosote requires at least 2 volumes of the 9 per cent, soda to dis- solve it. — Allen. CARBOLIC ACID. 399 parts of solution is revealed (Landolt, 1871), stellated needles appearing under the microscope. Corresponding precipitates, of nearly the same appearance, are given by the liomologues of phenol, by aniline and its homologues, by the phenols of wood- tar creosote, by certain alkaloids, and by other organic substances. With " cresylic acid," or crude carbolic acid, the precipitate is amorphous and soft.' Ferric chloride, as free from hydrochloric acid as possible, in solution with phenol gives a tine violet-blue color. Limit of dilution for this test, 1 part in 3000 parts (Almen, 1878). Acids and some neutral salts interfere. " On adding to 10 c.c. of a one per cent, aqueous solution of carbolic acid one drop of test solution of ferric chloride, the liquid acquires a violet-blue color which is perm.anent (the color thus caused by Creosote rapidly changing to greenish and brown, with formation, usually, of a brown precipitate) " (U. S. Ph.) But in more concentrated solu- tions this test does not clearly distinguish creosote from carbolic acid. Various organic compounds, and according to Schiff all compounds containing phenol-hydroxyl," give violet to blue colors with ferric salts. ' Laxdolt's original report upon this reaction, both in its qualitative and its gravimetric uses, is full and satisfactory. 1871: Ber. d. chem. Cfes., 4, 770; Zeilscli. anal. Chem., 11, 93; Chem. News, 24, 217. Of substances giving pre- cipitates with broraiiie-water, in solutions not too dilute, Landolt mentions quinine, quinidine, cinchonine, strychnine, and narcotine, all giving yellow or orange precipitates, soluble in hydrochloric acid, but insoluble in alkalies [a distinction from phenol]. As nut giving precipitates in dilute solutions, there are named gallic acid, pyrogallol, picric acid, bitter-almond oil, amygdalin, caCEeine, brucine, and hippuric acid. Morphine gives a white precipitate, soon dissolving. Wormley, in "Microchemistryof Poisons," treats of Bromine in so- lution of Hydrobroinic acid as a reagent for alkaloids, causing crystalline pre- cipitates with the greater number of them. 'That is, all phenols, and all derivatives of phenols which still retain one or more of the OH of phenols, give an iron-bluing reaction. Schiff enumerates, as giving blue colors, tannins, gallic acid, pyrogallol, other tannin derivatives, arbutin; as giving violet colors, phenols, salicylic acid, creosote, salicylic al- dehyde (oil of spiroea), methyl salicylate (CjHi.OH.COaCHj), saligenm, plie- nolsulphonic acid (CeHi.OH.SOsH), etc.; giving gree;;, colors, many tannins, assculetin, etc.; red and red-violet colors, phloridzin, phloretin, tyrosin, and some others. Morphine gives the blue color, and Cuastaing (ISSi) classes it as a, phenol. The reaction is not given with nitro-com pounds, nor with corn- pounds in which the II of phenol OH is displaced. — 801111']?. 1871: Aim. Chem. Phar., 159, 164; Zeilsch. anal. Chem., 10, 483; Jour. C/iem. Si/c, 24, JloH. — Hager states that the following substances interfere with this (est: organic acids, mineral acids, phosphates, acetates, borax, glycerin, alcohol, ainyl al- cohol. — Comparison of the reaction of carbolic acid, salicylic acid, resorcin, antipyrine, and kairine, with ferric chloride, is given by SnuwEisiNnicii. 1885: Arrhiv. d. Phar., 222, 680; Zeitsch. anal. Chem., 24, 4G!l. Distinction nC re- actions of carbolic, salicylic, gallic, and la.nnic acids, witli reiiic salts, II.igbr, 1880: Ding.polyt. Jour., 235, 407; Am. Jour.Phiir., 52, 2(i-l. 400 PHENOL. Molybdic acid in solution in concentrated sulphuric acid is reduced by plieiiol with the IVirination of a purple color. The molybdic acid is dissolved iu ten parts of the sulphuric acid, a few drops of tliis reagent, on a white porcelain surface, are cov- ered by a drop of the solution to be tested, and, after a momen- tary yellowish-brown coloration, the purple a])pears. To pro- mote the reaction tlie liquid may be slightly warmed, but not above 53° C. The reaction is a delicate one, but a similar color is given by many reducing agents. C'reusote, free from plienol and pure, gives only a reddish-brown tint (E. W Davy).' Quinine or Cinchonidine, as Sidphate or Hydrochloride, yields a characteristic crystalline compound witli phenol (IIesse"). The solution to be tested for plienol must be neutral. To this, while hot, a neutral solution of the alkaloid salt is added, one drop at a time, and so sparingly that phenol shall be in excess, if possible. If ])lienol be present a white precipitate appears, either at once or in crystals as tlie mixture cools, soluble in liot water, sparingly soluljle whi-n cold, almost insoluble iu phenol- water, easily soluble in acids, decomposed by alkalies, crystal- lizable from alcohol. With cjuinine sulphate the precipitate is (CooH24X„03)2HoS()4CyHgO. Tlie dextro-rotary cinchona alka- loids, according to ITesse, do not form these crystallizable phe- nolo-compouncls. Chlorate of Potassium may be used for the following test (Charles IticE^): Ten grains of the powdered clilorate, in a live-inch test-tube, are covered with strong hydrochloric acid to the depth of al)out one inch, the evolution of gas is allowed to Continue aliont one minute, when \\ volumes of water are added, and the gas is removed from the upper part of the test-tube by blowing it out with a small bent glass tube. Pour in water of ammonia, witliout shaking,' to form a layer about half an inch dee]), and remove tlie cloud of ammonium cliloride by blowing it out as l)etore. Now add a few drops of the liquid to be test- ed, letting it tiow down the side of the test-tube. If phenol be present a colored layer or " ring " will a})pear, rose-red to red- brown. Creosote gives the same reaction. 'An adaptation of Proehde's reagent. Davy: Phar. Jour. Trans. [3] 8, 1021; Jiii/r. I'linn. Snr.. 34, 809. The reagent for alkaloids: Froehde, 1866: Archiv. d. Phur., 126, 54; Zeitsch. anal. C/iem., 5, 314; Fro. Am Phnr Assn., 15, 241. Dragendorff, 1873: " Gericht. Chem. organ. Gilte." Tliis work, p. 51. '1876: Liehig's Aniialeii, 181, 53; 180, 248; 182, 160; Jour. Chem. Sac, 30, 313, 639; note by Wright, 314. n878: Am. Jour. Phar., 45, 98. CARBOLIC ACID. 401 Other tests are obtained by action of Aninionia and Chlorine, Ammonia and Hypochlorite, and by Millon's reagent.' Pure phenol does not reduce Fehling's solution, and but slowly reduces silver and niercui'}' salts, but reduces jjermanga- nate, both in acid and in alkaline solutions. With concentrated sulphuric acid, phenulsuljyhuiiic acid, CgllijSO^, is slowly form- ed, almost without color when the phenol is pure. The pheuol- sulphonates of alkali metals are soluble in alcohol, and those of other metals, including barium and lead, are soluble in water, these solubilities giving separations from sulphuric acid. On distilling phenolsulphonic acid, phenol is obtained. See JSulpho- carbolic Acid. '• Carbolic acid coagulates albumen or collodion (difference from creosote). . . . One volume of liquetied carbolic acid, con- taining live per cent, of water, forms, with one volume of glyce- rin a clear mixture which is not rendered turbid by the addi- tion of three volumes of water (absence of creostite and cresylic acid)."— U. S. Ph., 1S80. e. — Separations. — Carbolic acid can be obtained hy distilla- tioii from acid or neutral liquids without loss. Less volatile than water, the phenols are yet carried over, slowly, with vapor of water, and the operation requires conditions similar to those needful for distillation of the essential oils. In alkaline aqueous solutions the phenols are held nearly or quite secure fi-om vapori- zation, so that these solutions can be cdnceniritUd on the water- bath without loss of phenol, though as to the limits of the reten- tion of phenol by hot alkalies when very dilute further proof is desirable. Potassium hydrate is the best alkali. Alcohol and other more volatile neutral bodies are easily rem(j\cd by evapora- tion or distillation from alkaline mixtures of carbolic acid. Be- fore distilling j'henol, therefore, alkaline liquids and mixtures — sucii as "carholate of lime" and "soda-phenol" — should be acidified by adding an acid, in most cases sulphuric acid, some- times hydrochloric or phosphoric acid. But phenol may be dis- tilled, with water, from a neutral mixture. Dry distillation, ' Ili-tiiili;il reports upon qualitative tests for phenol Ijave been given as fol- lows: Waller, 1881: School of Mines Quatterhj, If^Hl, .Jan.; Chem. News, 43, 151. Almen, 1S77: Archir.d. Fliiir. [y] 10, 44; Jour. Clwm /S'oc, 32, 300. Allen, 1878: Ana/i/st, 3. Sl'J; Jour. C/iern. iSoc.,36, 183. IIirsciisoiin, Phenol and Thymol, Dorpat, 1881: Phar. Jour. Tians. [I!] 12, 21; Am. Jour. Phar., 53, 459; Jour. Cheiii. Hoc, 40, 942. Regarding Detcetion and Khtinialioii in the Urine — Baumann, 1882: ZciUcli. plijjsiohxj. (J/u'in., 6, 1H:!; J-mr. Cheiti. Hoc, 42, 106. Enhkl, 1881: Ann. Chiiii. P/ii/.-i. [5] 20, 330; Jour. C/win. Sac, 40, 114. 402 PHENOL. without addition, in glass vessels over the flame, is directed by Allen for recovering from the siliceous material of " carbolic acid powders." In analysis of animal tissues, or indeterminate organic mix- tures, in cases of poisoni7ig, the finely cut material is digested, after slight acidulation with sulphuric acid, to obtain an aqueous solution of all the phenol. If concentration of the extract is undertaken before distilling, the analyst must choose a method suited to the material and conditions. Extraction with ether has been recommended in this case, and it may serve if there is little fat. The ether solution may be shaken witli very sligiitly alka- line water, the ether-layer and dissolved ether evaporated off, and the aqueous solution acidified and distilled. In any case the last distillate is divided into aliquot parts by volume, for quali- tative and quantitative determinations, the bromine reaction being most serviceable. ' Phenol is eliminated freely by the kid- neys. In the Urine phenol appears in salts of phenylsulphuric acid, chiefly KCgHgSO^ , formed by union of the excretory phenol with the sulphates of the urine. Therefore it is a chnical result that the sulphates of the urine, as noted by the precipitation of barium, diminish in measured proportion to the increase of ex- cretory plienol. The later investigations'" carefully distinguish the urinary form of phenol, above named, from its isomer, phe- nolsulphonic acid (see Sulphocarbolates). When much phenol is excreted, and in cases of phenol poisoning, tlie urine some- times, but not invariably, has a greenish-brown color. Buumann separates the sulphates from the phenylsulphates and determines the sulphuric acid of the latter and of other ethersulphuric acids as follows : 25 to 50 c.c. of the urine is acidified with ace- tic acid, diluted with an equal volume of water, treated with an excess of barium chloride solution, and warmed three-quarters of an hour on the water-bath, for the full precipitation of all the simple sulphates. The filtrate is boiled with hydrochloric acid to decompose the conjugated acids and throw down their sul- phuric acid as barium sulphate, which is tlien washed with hot ' Vox the Toxicology of GarboUe Acid, including analysis, see Wharton and Stille, " Med. Juris.," '4th ed. 1884, vol.3, p 96. Blvth's "Poisons," London, 1884. Engel, 1881: Ann. Ghim. Phys. [5] 20, 2.80; Jour. Chem. Soc, 40, 114. J'ascHOFF, On distribution in the body, 1883: Ber. d. chem. Ges., 16, 1337; Jour. Chnn. Soc, 44, 1030. ' Baumann, supported by Clobtta and Schaeb,. CARBOLIC ACID. 403 alcohol to remove resins, etc., and prepared for weighing. The phenylsulphates are more easily decomposed by mineiul acids and heat than the phenolsulphonates. From the weight of barium sulphate obtained by decomposition of the phenyl- sulphates the quantity of excretory phenol is calculated : BaSO^ : C6HeO::232.S : 94.0 ::1 : 0.40378. The phenol of the urine may also be estimated by distilling at length, adding hydrochloric acid to liberate phenol from the phenylsulphates, and determining the phenol, in the distillate, by the volumetric method with bromine. In separation hy solvents, ether, hot water, and alkaline water are most serviceable, but carbon disulphide, benzene, and chloroform may be employed. Petroleum benzin takes up but traces. Ether extracts the phenols from aqueous solutions not alkaline, and from other materials not acted on by the ether. It is to be applied in repeated portions till no more plienol is obtained. Liquids are to be shaken witli the ether in a test- glass or stoppered cylinder, when the ether-layer is allowed to rise and is taken off. Tliis is well done, exactly as M-ater is ex- pelled from an ordinary wash-bottle, the delivery tulx' (not too large) playing up and down in the stopper to take up the ether (p. 36). Or, with use of a separator, the watery layer may be drawn away. The ether may be removed by spontaneous evapo- ration, or in a current of warm air driven by a bellows or drawn l)y a lilter-pump, with very little loss of the ])henol. But to prevent this loss it is well, if the operation permits, to add enough water, made slightly alkaline with potassium hydrate, to take up the phenol from the ether-solution. Hot water extracts carbolic acid from fats, a very thorough application being need- ful. From animal tissues acidulated hot water has been mostly used, sulphuric acid aeidulation being preferred. Jacousen (18>;5) extracted with benzene or ether.' Materials not at all act- ed on by alkalies may be most efBciently exhausted of phenol by water alkaline with about nine per cent, of potassium hydrate. The water solutions, neutral or acid, if pure enough to iXMjuire no further separation, are ready for precipitation of phenols by bromine, as directed for the Quantitative work. In the viihuition of dnide ('arlxiUc. Acid the per cent, of tar-oils is briefly found (Allen) by shaking, in a graduated tube ' W. Jacobsen, 1885: Doipat Dissertation : Zeilsch. anal, ('hem., 25, 0(17. 404 PHENOL. or jar, with a nine per cent, caustic soda solution, and reading off the resulting layers of undissolved liquid (substances besides phenols and water). But some naphthalene and other non-phe- nol bodies are dissolved by the alkali, which therefore must be as dilute as will barely dissolve the phenols. An equal volume of petroleum benzin previously added, and accounted for, dimin- ishes the solution of " tar-oils " by the alkali. An assay iy dis- tillation of the crude carbolic acid is used at works (Charles Lowe '), the phenol distillates being compared in solidifying points with known mixtures of good carbolic and cresylic acids. Phenols may be separated or estimated in special cases by conversion into phenolsulphonic add. The latter may be ob- tained in its soluble bariuui salt, and the barium precipitated as a sulphate, one molecule of barium sulphate denoting one mole- cule of the phenol, the same as from the phenylsulphate above given. The formation and characteristics of the phenolsulpho- nates are to be observed, as givezi under iSulphocarbolates. f. — Quantitative. — For chemical estimation the precipitation with bromine appears to be best suited. The precipitate was stated by L.vndolt" to be Q^r^v^^^'^>Z<)A\ and when it was washed with water, and dried in a desiccator, this author ob- tained fair gravimetric results. The precipitate, however, is not easily washed, and it botli melts and vaporizes on tlie water- bath. The volumetric method is more satisfactory. Waller' em- ploys an aqueous solution of bromine- by which the solution es- timated is exactly compared with a solution of phenol of known strength. Koppeschaab uses a standardized solution of 5K!Br-(-KBr03, added in excess, then acidulates, and titrates back with thiosulphate solution (also used to standardize the bromide), with use of iodide as an indicator.'' SBrBERT,' estimat- ing phenol in Surgical Dressings, found it necessary to tilter before adding the iodide, as tribroraophenol liberates iodine from iodide. Weinreb and Bond: ° report that the precipitate is not CgllgBrgO, but CgHgBr^O or (C;elToBr30Br), and that Koppe- schaar's correct results were indebted to the reaction with the iodide of potassium used as an indicator (in presence of the pre- ' Allen's " Commercial Organic Analysis," 187H. i. 311. '' Ber. d. chem. Oes., 4, 770; Ghem. News, 44, 217. See Weinreb and BoNDi, below. S1881: Cliem. Nexos, 43, 157. '1876: Zeitsch. anal. Chem., 15, 233; Jour. Chem. Soc, 31, 746. Dege- NER, 1878: Jour. pr. Chem. [2] 17, 390; Jour. Chem. Soc, 34, 918. ''1S82: Arch. Pliar. [3] 18. 321; Jour. Chem. So,- , 42, IO6. "1885: Munat. f. Chem. (18S5), 6, 506; The Analyst, 11, 39. SULPHOCARBOLATES. 405 (•ipitate), whereby CgHgBrgO is at last formed, when (as Seubert .states) iodine is liberated. Chandelon ' uses bromine dissolved in dilute alkali solution, as hypobroniite, the estimation being applied io the Urine, as well as to surgical dressings. As to estimations in the urine and in dressings, the method of Bau- MANN has been given under p. 402. The directions given by Dr. Waller, in the method tirst above named, are as follows : Solutions required : (1) Ten grams pure crystallized phenol [of the dryness desired a^ a standard] in water to make 1 liter, a solution not siiffering alteration for some months. (2) A solu- tion of bromine in water. (3) Diluted sulphuric acid, of 15 to 2(» per cent, strength, saturated with alum. This is needed to enable the precipitate to settle. Of the sample 10 grams are in- troduced into a liter-liask, water is added, with agitation, to make one liter, the solution mixed and some of it filtered (through a dry filter). Of the clear filtrate lo c.c. are run into a six or eight ounce glass-stoppered bottle, and about 30 c.c. of the alum solution are added. In another bottle of the same kind 5 c.c. or 10 c.c. of the standard phenol solution are taken, again with about 30 c.c. of the alum solution. Bromine solution is now added, from the burette, to the bottle containing standard phenol solution, till no more precipitate forms, the bottle being stop- pered and shaken after each addition, for the separation of the precipitate, and the end-reaction being further indicated by ap- pearance of a yellow color in the clear solution when a' very slight excess of the bromine is reached. Near the end the pre- cipitate forms slowly. The solution from the sample is titi-ated in the same way. Then, c.c. of bromine- water required for 10 c.c. standard phenol sol. : c.c. bromine- water required for 10 c.c. from sample :: 100 : x = percentage of the standard phenol in the sam):)le. g. — Impurities in (Jarholic Acid. — Alkaline dilutions are re- vealed by their iilkaline reaction, and by giving a precipitate when neutralized by adding dilute sulphuric acid. If an article presented as liquid carbolic acid, pure or impure, is freely misci- ble with water, it may be either the very dilute carbolic ai'id water or an alkaline mixture. Regarding the Tar Oils see p. 404. Concerning the quality of " ( !ai-bolic Acid of America," E. M. Hatton, ISMG : Proo. Am. Pharvi., 34, 70. SuLPHocARBOi.ATEs. — Salts of phenolsulphonic acid, Cgll^. ' 1882: Bull. Sue. Chim. [2] 38, 69; Jour. Ctivm. Soc , 44, Abstracts, 124. Further, Cloetta and Schabii, 1881-82: Jour. Cheni. Soc, 42, 106. 4o6 PHENOL. OH . SO3H (CgB[gS04 = 174, monobasic). Phenolsulplwnates. Sulphoplienates. Phenolsulfosauresalz. — There are two phenol- sulplionic acids easy of production and liable to occur in sulpho- carbolates of commerce — namely : (1) Phenol orthosulphonic acid, having OH : SO3H = 1:2, produced by continued con- tact of phenol and concentrated sulphuric acid in equal parts at ordinary temperatures, and the proper constituent of medicinal sidphocarbolates. (2) Phenol para-sulphonic acid, OH : SO3H = 1:4, produced by heating the ortlio acid. Phenol disulphonic acid, CqH3.0H.(S03H)2, is formed by heating phe- nol with excess of sulphuric acid.' Cresolsulphonic acid and xylolsulphonic acid are formed when crude carbolic acid or other mixtures of cresol and xylol are digested witli concentrated sulphuric acid. In preparing phenolortliosulphonic acid equal parts of phenol and concentrated sulphuric acid are mixed, after twenty-four hours water is added, and, in some way, the (unavoidable) free sulphuric acid is removed. This may be done by saturating both the phenolsulplmi-ic and sulphuric acids with barium car- bonate and filtering; or by carefully saturating only the sulphuric acid, so that the filtrate shall precipitate neither a barium salt nor a sulphate ; or by saturating both acids with sodium carbon- ate, evaporating, dissolving the phenolsulphate in alcohol, and crystallizing from the filtrate. The higher the temperature of action of the sulphuric acid, and the greater the excess of this acid, the more of phenolparasulphonic acid will result, and its production is not wholly avoided in any case. The potassium phenolorthosulphoiiatu melts at 2-40° C, and crystallizes in needles with two molecules of water ; tlie potas Slum phenolparasulplionate melts aliove 260° C and crystallizes, anhydrous, in hexagoiiiil plates.' Phenolsiilplionates are decom- posed with reproduction of suljahuric acid, by boiling with nitric acid or with hydrociiloric acid, and slowly by boiling with water. The nitric acid reacts vigorously, as with phenol, forming uitro- phenic acids. Even in water solution at ordinary temperatures free phenolsulphonic acid suffers gradual decomposition. The metallic sulphocarbolates are all measurably soluble in water, the barium and lead salts included (separation from sul- phates). The sodium salt is ]SraCuH:5S04.2HoO. The alkali ' Sulphuric acid, H0(S03H)' or H0(S02)"0H Phenolsulphonic acid, HO.C0H4.SO3H [CeHsSO,] Piienoldjsulphonic acid, HO.C'oris.CSOsH)! Phenylsulphuric acid, CeHsO.SOsO [CoHeSOJ ° "Watts's Dictionary," viii 1538. PLANT ANAL YSIS. 407 sulphocarbolates are soluble in much alcohol (another separation froin sulphates). Further, the sulphocarbolates are idinUiJiedhj giving the chief reactions of phenol— those with niti'ic, acid, bromine, and ferric chloride — and 1)/ giving the reactions of sulphates only after decomposing with boiling nitric or hydro- chloric acid. PHYSETOLEIC ACID. See Fats and Oils, pp. ai(;, 250. PICRACONITINE. See Aconite Alkaloids, pp. 18, 20. PITURINE. See Midriatic Alkaloids, p. 341. PLANT ANALYSIS.— 77ie chnniad analysis of vegeta- hl-e tissues. Phytuchemical analyt^is. Systematic methods of chemical analysis of plants have been presented as follows : Frederick Rochlbder, JI.D., professor ol organic chemistry iu tlie Uni- versity of Prague, 1858: Wiii'zburg, Germany. Englisli translation by Wil- liam ijastick, London, IStiO: Pkar. Jour. Trans. [2J 1,503. Same translation revised by Professor Joliu M. Maiseh, Philadelphia, 1860: Am. Jour. Phar., 33, 81, tt sei/. ; reprinted in 80 panes, lH(i2. Dr. G. I'. WiTTSTEiN, Jliiiichen, 1808: " Aideitungzur chemisohen Analyse von Pflanzentheilen auf ihre i>ri,'anischen Bestaiullheilen," :j.j."ipp., Xurdlingen. An English translation, "The Organic Constituents of Plants and their Chemi- cal AnalT!,cs," by P. \on Mueller, Ph.D.. F.li.S., Jlelhourne, 1878, pp.333. The " plant analysis" is included in Part II., 49 pages. IIkn'RY B. Parson's, Ph.('., assistant chemist in the Department of Agricul- ture, Washington, 1880: "A Method for the Proximate Chemical Analysis of 'Plants," American Chemical Journal, i, o7T-o!ll; Am. Jour. P/iar., 52, 210; Pilar. J.iir. Traii-s. [3] 10. Tit:!; Jour. Cliem. l^nc. (abstract), 38, 754; Ber. d. chrm. Ges., 13, KJTO; (Jlicni. iVcim (in full), 41. i!5(i, 2(i7; Vear-boolc of Pliar., London, IXHO, 5n: Jahrcs d. Pharm., ISM), !)!i: Allen's "Commerciiil Organic Analysis," London, second edition, lSy5, 1. :;5ll (laljiilated abstract); Lyons's "Pharmaceutical Assaying," Detroit, 188(1, p 37 (taliulated abstract). — Given in full in th- following pniji'i. Georo Draoendorfp, professor of pharmacy in the University of Dorpat, Russi.i, 18W3; "Die f|ualitative und quantitative Analyse von Pilanzen und Pflaiizeiitheilen,' 285 pp , Gottingen. An Knglish translation by llniry (i. Greenish, London, IMSi: '• Plant Analysis: Qualitative and Quantitative," 2S() pp. A French translation in Fremy's •' Eiieyelo|ii'die Chimiqne," Paris, 1,SS5, tome viii. (from the author, without eredil to previous publication). An out- line of Dragendorff's xclioiie in given in the following jxiges. Good examplesot plant analysis, chiefly according to Dragendorff's scheme, have been presented by Helen C. DeS. Abbott, Philadelphia. In 1884, analysis of " Fouquiera splendens," /'ror. Am. ^Is.soc. Adv. aration of Sample. The air-dry specimen should l)e carefully examined, and all extraneous substances removed. The entire sample should then be ground, or beaten in an iron mortar, until it will all pass through a sieve having from 40 to 60 meshes to the linear inch. After thoroughly mixing this sample, take of it about 100 grams, which should be further pulverized until it will all pass through a sieve having from 80 to 100 meshes to the linear inch. From this smaller portion remove all iron, derived from mill or mortar, by use of a magnet. Then place in a clean, dry bottle, which should be labelled and securely corked. This small sample is for the analysis ; the larger portion should be I'eserved for the sepa- ration of those proximate principles which seem, from the analy- sis, to be worthy of ui(,)re extended investigation. II. Esthiuiiion of Moisture. Dry rapidly, at 100° to 120°C., two or more grams of the sample ; the loss of weight equals moisture and occasionally a little volatile oil. In some cases it is best to dry at a lower tem- perature, and at other times tiie drying should be conducted in a stream of hydrogen or carbonic anhydride.' III. Eatimntion of Ash. In a weighed crucible gently ignite two or more grams of the sample until nearly or quite free from carbonaceous matter ; the heat should not be permitted to rise above faint redness, or loss of alkaline chlorides may occur. "Weigh this residue as crude ash. and in it determine : a. — Amount Soluble in Water. — This portion may contain chlorides, sulphates, phosphates, and carbonates of potassium and sodium ; also slight amounts of chlorides and sulphates of cal- cium and magnesiun). ' On treatment of fresh plants for drying, and on methods of powdering, see Dragendorff's " Plant Analysis," London edition, p. 6. PARSONS' S METHOD. 411 1). — Insoluble in water; Soluble in Dilute Ilydrochloria Acid. — The residue from a should he treated witli a slight ex- cess of hydrochloric acid, and evaporated in a porcelain dish over a water bath until all free acid has been expelled ; it should then be aijain moistened with hydrochloric acid, water added, and be iiltered from any remaining insoluble substances. This treatment removes carbonates (with decomposition) and phos- phates of calcium and magnesium, sulphate of calcium, and ox- ides of iron and manganese. c— Insoluble in Water ; Insoluble in Dilute /[ijdrockloric Acid ; Soluble in coneeidrated Sodi/uni Hi/drate. — Boil the resi- due from b with a solutit)u containing about 20 per cent, of sodium hydrate. This treatment removes combined silica of the ash. The residue still insoluble is sand and clay which adhered to the specimen ; this residue should be separated, washed tho- roughh', and weighed. Always determine the amounts reinoved by the above treat- ment bv weis:hinitated by nne ntagent from the amount precipitated by the ether To the filtrate add a slight excess of dilute hydrochloric acid, boil gently for half an hour, and determine in the liquid total glurose by use of Feliling's solution. 1 For this estimation methods are given in the nrticle on Tannins in this work. Mr. Parsons advised the gravimetric method of Cabpeni (1875: Jahr. der Chem., '■)"*'.): ff/i.em. News, 31, 282). Pi-ecipilafe by ammoniacal acetnte of zinc, use a Gooch's filler, wash the prceipitati^ with very weak ammonia, dry at 120' C, weigh, ignite cautiously, again weigh. The loss by ignition equals tannic acid, in absence of certain interfering substances. 4i6 PLANT ANAL YSIS. 7. Precipitate 30 c.c. by subacetate, exactly as in 6, and use tlie precipitate as a duplicate to check the amount there estimated. To the filtrate add a very slight excess of salution of carbonate of sodium, filter from the carbonate of lead, wash well with water containing a little alcohol, and in the filtrate esli- raate actual glucom. If the glucose thus found is appreciably less than that in <5, subtract it from that amount; this glucose maybe due to the presence in tlie plant of sucrose or some glucoside. It due to sucrose, the amount of the latter may be found by multiplyuig this residual glucose by 0.95; if to a glucoside, a tit subject for an extended investigation is presented. The properties, formula, and decomposition products of the newly found glucoside should be carefully studied. 8. Precipitate 20 c.c. with subacetate of lead, as in 6 and 7, employing the precipitate as material from which to separate organic acids, after removal of lead by sulphuretted hydrogen. Acidulate the filtrate with sulphuric acid, add an equal volume of alcohol, allow to stand two hours, filter, wash the precipi- tate with 50 per cent, alcohol, and evaporate the filtrate until all alcohol has been dissipated. Test the acid solution for alkaloids, glucosides, sugars, ex- tractives. 9. Reserve tV-.e remaining 40 c.c. for duplicating any unsatisfactory deter- minations. 10. 'rhe residue mentioned in 3 as insoluble in water may contain resins, alhmninoids (especially from seeds), colors, alkaloids, glucosides. Dilute acids remove alkaloids and some glucosides; dilute ammonia water will remove some resins, colors, and glucosides. Any still insoluble residue probably con- tains albuminous or resinous substances. VII. Esthnatioii of Cold Water Extract. That part of the plant remaining insoluble after treatment with alcohol shonld be dried at 110° C. and completely extract- ed by cold water. When the plant contains considerable mu- cilaginous matter this is best removed by placing the sub- stance in a flask or graduated cylinder, and then adding a mea- sured volume of cold water. Allow to macerate, with frequent agitation, for from 6 to 12 hours, then filter through fine washed linen, and evaporate an aliquot portion of the solution. In this residue determine totnl organic matter and a.sJi. This residue usually contains little l)ut (jum. ; in analysis of fruits and fieshy yooi%. pectin Ixulles, salt.^ of organic acids, rarely a substance re- sembling dextrin, and small an)ounts of adnimincnis siihstances and coloring matter. Usually the separation of these substances is very difficult. The unevaporated liquid should be used for such qualitative reactions as are necessary to show the nature of the substances extracted. The insoluble residue should be well washed with water, transferred to a crucible, and completely dried at 110° C. This residue should then be weighed. VIII. Estimation of Acid E.dr acts. The dried residite insoluljle in cold water should be trans- ferred to a beaker containing 500 c.c. of water and 5 c c. of con- centrated sulphuric acid (sp. gr. 1.84). Boil for 6 hours on a PARSONS' S METHOD. 417 gauze support, adding water to keep the volume of liquid un- changed ; if the substance he very starchy a longer Lolling may be necessary. This treatment will convert starch and its amor- phous isomers to dextro-glucose, and will ocoasionally remove some salt of an orijanio acid, with usually traces of aWuminous and indeteDihinate substances. The total, amount extracted may be found by washing, drying at 110° C, and weighing the yet insoluble residue, and subtract- ing the weight from the one taken after extracting with cold water. The amount of starch and iso?ners may be found by determining in a given volume of the acid hltrate the amount of glucose, using Fehling's solution ; the glucose thus found multi- plied by 0.9 equals starch and isomers. The total extract minus starch and isomers equals acid extract not sturch.. This includes a small amount of ash, whicli may be approximately determined by evaporating and igniting a known volume of the solution. Where it is wished to separate the extracted matter from the sulphuric acid, boil the liquid with an excess of powdered barium carbonate until no acid reaction remains. Filter and evaporate to dryness. The residue consists chiefly of hydrated dextro- glucose (CglT^gOg . HoO), with some ash. IX. Estimation of Alhdl Extract. Wash well and dry at 110° C. the residue from treatment with acid, and record its weight. Boil this residue for two hours with 500 c.c. of a solution containing 20 grams of sodium hydrate to the liter. Filter through fine washed linen, and wash the residue thoroughly with hot water, alcohol, and ether. Transfer it to a weighed crucible, dry at 110° to 120° C, and weigh the residue as crude fibre and ash • this weight subtracted from the previous one shows the total alkali extract. This ex- tract is largely (dhuminous matter and various modifications of pectic acid, Fremy's ^^ outose," and various coloring, humus, and decomposition compounds, in small amounts. Most of the ex- tracted substances may be precipitated by excess of an acid with or without the presence of alcohol. X. Cellulose. The crude fibre from IX. should be treated with from 50 to 100 c.c. of U. S. Ph. solution of chlorinated soda and allowed to stand twenty-four hours. If not then bleached white, slightly acidulate vdth hydrochloric acid and set aside for another day. Filter through fine linen or Gooch's filter, wash with hot ^\'ater. 4 1 8 PL A NT ANAL YSTS. dry at 110° to 120° C, aud weigh, ash-free, as cellulose. The loss of weight by this treatment state as lignose and color. Recapitulation of Parsons' s Method. I. SampHng, pulverization, and preservation of an air-dry portion in constant condition for an analysis. II. Estimation of moisture by loss at 100°-120° C. III. Estimation of Ash. a. Portion of the ash soluble in water. i. Insoluble in water; soluble in dilute hydrochloric acid. c. Insoluble in water or in the acid ; soluble in sodium hydrate solution. I"V. Estimation of the total nitrnyen. For cliecli on results; for calculation of albuminoids after estimation of alkaloids, etc. "V". Estimation of portion soluble in benzene (oe.chloeo- foem). 1. Portion of benzene extract vaporized with benzene : volatile oils {camphors). 2. Portion of benzene extract soluble in water : alka- loids^ glycosides, organic acids. o j Not soluble in water, ) Alkcdoids,^Q%%\kA^^ glu- ■ I soluble in dilute acid : j cosides. i Removed hj animal charcoal : chloro- phyll, some 'resins. !Not removed by the charcoal : some resins. i Not soluble in water '\ 5. < or the acid, or in al- I W(i.xes, fats, fixed oils. { cohol of 80^ : ) VI. Estimation of poetion soluble in alcohol of 80,'^ (after removal of V.) The solution is made up to a defi- nite volume (200 c.c.) In two equal aliquot parts (20 c.c. each) residues are obtained to furnish (1) the amount of organic matter, (2) tlie ariwunt of organic matter .lolidAe in vjater, thence the amount of or- ganic riKdter iiisoltible in 'water. In " THE first way " the constituents of VI., in the re- maining 160 c.c, are primarily divided according to their solubility in absolute alcohol, then by further treatment, as follows : Not soluble in water or the acid. Soluble in alcohol of SOfo. PARSOAS'S METHOD. 419 A. Soluble ill (ihsi)laie alcoliol. a. Soluble in water. Wuiglit obtained. a'. Precipitated by subacetate of lead. Tannin and most oi'ganic acids; some ex- trddives; some iiiurtjauic acids of the asli. Weight of all obtainod. a". Not precipitated hy subacetate of lead. All'iiliiiils, (jJucosliIes, extfactivcn:, colors, a — af =^ a" . h. Insoluble in water. \V^ eight obtained. v. Solul)le in dilute hydrochloric acid. AlIcaIoi(h, rarelv glucosides, extractives. h-h" = V. v. Insoluble in dilute liydrochloric. Weight taken. h'". Soluble in dilute ammonium hydrate. Most acid ivs/'/is, some colors, h" - h"" = h'". V" . Insoluble in the ammonia. Weight taken. Keutral reslna, some colors, albuin'moids. B. IriKohihle in ahsolnte alcohol. C. Soluble in water. c'. Precipitated by sul)acetate of lead. Cohnv, < xtract'ives, rarely (i/l>iiniijio/itated by subacetate of lead. Alkalo/ds, glucosides, glucose, sucrose, extrac- tives. c— d ^ c". Estimate sugars. d. Insoluble in water. d'. iSobible in dilute hydrochloric acid. All'idoids, glnciisides. d — d" ^d' . d" . Insoluble in dilute hydrochloric acid. Yg.\\' resins, exti-actives, colors. Weigh. In "the second way" tlie constituents of VI., taken in the remaining 1(10 c.c. of SC;/ alcohol solution, air pri- marily divided aee(_irding to their solubility in water, then by other treatment, as follows: (3) Evaporate to dryness, add wati^r, reserve the residue (10), and make the filtrate up to Kill cc. (4) In 20 c.c.. estimate ^/r!«v«. (5) In 20 c.c. estimate total precipitate by lead normal acetate. Tannins.^ acid'i (inorganic and organic), colors, extractives. 420 PL A NT ANAL YSIS. (6) In 20 c.c. estimate tota] precipitate by lead basic acetate. Compare precipitate with that in (5). In filtrate estimate the total glucose of sugars and glucosides. (7) In 20 c.c. duplicate the precipitation of (6). In filtrate estimate the actual glucose. Compare with total glucose. (8) In 20 c.c. ti-iplicate the precipitation of (6). Ex- amine the precipitate for alkaloids, glucosides, sugars, extractives. (9) Use the remaining 40 c.c. for additional exami- nations. (10) The residue left in operation 3 may be tested for resins, albuminoids, colors, alkaloids, gluco^ sides. VII. Estimation of the portion soluble in cold water (after removal of V. and VI.) Examine as directed in the text, making up the filtrate to a definite volume, and taking aliquot parts (1, 2, 3, 4, etc.) for determina- tions and tests. In (1) determine total solids, and then the ash, to find the total organic suhstances. Gams, pectou.s substances, salts of orgaibic acids, dexti'ins, soluble starches, albumens, colors. Examine by solubilities, iodine test, estimation of nitrogen, etc. The residue from solution VII., dried at 110° C, is weighed. VIII. Estimation of portion soluble in boiling dilute acid (after removal of V., VI., and VII.) Tlie weight of the washed residue obtained for estimation of the total solids of VIII. Starches estimated by determination of glucose with Fehling's solution, first examining for interfering extractives of a reduc- ing power. An aliquot portion of the liquid, freed from the sulphuric acid, is tested in portions quali- tatively. Small amounts of albuminoids may be found. IX. Estimation (jf portion soluble in alkali-watee (after removal of portions V. to VIII.) Take weight of insoluble washed residue, for estimation of total sol- ids. Alhum.ens, forms of pectin, humus, decomposi- tion products, colors. X. Estimation of the residue left by solvents V. to IX. Cellulose, lignose, colors, ash. Estimate from sepa- ration by chlorinated soda solution. PARSONS' S METHOD. 421 Jiemarks.' It is advisable to determine always, in addition to what has already been directed, the amounts extracted directly from the sample by water, ether, alcohol of various percentages, methyl alcohol, bejizin, chloroform, carbon disulphide, etc. In each extract estimate total organic matter and ash, and determine qualitatively, and quantitatively when possible, its constituents, by treating with such solvents and reagents as are indicated. Eacli extract being com- posed of certain distinct substances, it is necessary to account for them in every case. The amounts present of some constitnents may be found by subtracting the weight extracted by some one solvent from the weight extracted by some otlier. It will be seen that this is a method of limited applicability, which can only be applied in those cases where the diiference between the solvent action of the two liquids is very sharply defined. Certain special methods for the esti- mation of single constituents may be used, care being taken that all interfering substances be first removed. The methods of preparation of known subslances as given in Husemann's " Pflanzenstoffe," and to a considerable extent in " Watts's Dictionary," may serve as suggestions for work. Treatment with ben- zene, 80 per cent, alcohol, and water, removes from nearly all plants the con- stituents of greatest chemical and medicinal interest, but in analyses of grains, fodder, and food materials, those compounds extracted by dilute acids and alka- lies have great value. T''here are substances in plants, seemingly isomers of starch and cellulose, which have properties more or less resembling those of cellulose, and are changed by boiling with dilute acids to glucose. In absence of an established nomenclature it has seemed best to use the terms "starch isomers " or "amylaceous cellulose" for these substances,' while those consti- tuents, not albnmiiioiix, which are removed by dilute alkali have been termed "alkali extract." These substances have been investigated by various chemists, but no definite and authoritative nomenclature has yet been adopted. Thom- SEN gives the name " holz-gummi," ' wood-gum, to a white substance extraoted from plants by dilute sodium liydrate, while Premy regarded these various com- pounds .as modifications of pectic acid, pectin, and "cellulose bodii'S.'" Starch also may exist in some seeds (as of sweet corn) in a form soluble in watf-r." It will be seen that the field for investigation is limitless, and that there is great need for improved methods for proximate analysis. The analyst will find that a study of any common plant will require of him much more than unthinking, mechanical habits of manipulation, while every careful investi- gation will reveal to him some constitnents deserving more full and accurate study. ' By Henry B. Parsons. ' U'. S. Dopt. of Agric. Report, 1878, p. 189. 'Jour, prrtk. Chcm., 19, 146. 'Compt. rend., 83, 1136; Jour. Oh em. Soe.. 31, 239(1877). 'II. S. Dept. of Agric. Report, 1878, pp. 15:!-155. 422 PLANT ANALYSIS. cv. ^ o o O CJ o '^1 CD tp CZJ QJ U U U 1^ 0-. CW o ^^ *^^o,ocudc56 "T 6 -S-g£oo£22igg o£ <§ |z;;z;fL|^:zia^fL,|l^(^pHP^ ^(^ , O .<^ O o- II CD'O O) OJ • -'U . OJ • §1 :.:::::^>-'n^..»- p- ^^ tS -»j T^ ts -t-^ n:3 .cg^.=^-z5^^£cfi«^^^£a^^=^^£^££ ^ c^. o- cv. c^- o- ■w-io/oMiyo o c ci.d-3o cgS£-^oSiS£SSi3Sgi£S MMMCA. Cn73MM>=H^XC/j^^^l-HH-.M>=l-l^^^l-lM" ■ —• ._;_;_:,/: y: ^ _: „: „; .,: ,y ,,; i j, « v ■/ oi » »: ■j.9iifz -sqr ooi:i.c.oo=ccC-cop- = £iicf:s = ccc MMtBKMM-J-.'h^MC/Jcr. ro — ►-iwMf^MMh-;Mh-^ y^ *^ ^ y^ ^ 'J^ ^ ^ ^-f^ 'f^ 'S^ rJiy=<'f.^fi^^^^^XIl X .' CO ! ■ T3 . "-^ "^ • - ' i i> en . - !«.2 •;. : S o m ■ V ^ ' cc Q. Is... loids icid . acid org. ■ellul cellu lose' ctive =: cq a: a O O' - O I^ '^ ^ i ^ C Alkalo Album Pectin ■5 °-S^ " Para "Meta ' ' Vase "Extr Colors "5 ":; 5 (u 'C t 4- 05 d DRAGENDORFF'S METHOD. 423 Odtline of Dkagendokff's Method of Plant Analysis.^ For the systematic analysis 30 to 50 grams may usually he taken. From 2 to 5 grams are dried at 100°-llU° for total moisture ; and usually another portion, not above 30° C, for amount of loss. The material for the systematic analysis to be powdered, sampled, mixed, and very iinely pulverized for sol- vents. Very hard bodies are dried at 100° to 110° C. before pulverizing. Fatty bodies may be tirst treated with the petroleum benzin. For ignition pulverize very hue, and if need be, after partial ignition, pulverize again. To promote combustion am- monium nitrate may be added, or ignited and weighed ferric ox- ide may be introduced. Powdered glass or washed sand may be intermixed. The carbon dioxide of the ash is to be determined. Special methods are used for the full quantitative estimations of distinct substances. I. Solution by petroleum benzin (petroleum-ether, petrole- um spirit). — This solvent to boil to the last at -i.)" G. and leave no residue. Use 10 c.c. for each gram of the dry plant pow- der. Macerate eight days, shaking daily. Aromatic fresh plants may be treated, witliout previous drying, by line division, and by percolation with the solvent. Receive in a graduated separator, and take off aliquot volumes for examination and for weight of total dissolved sul)stanees. To evaporate the soloent from essential oil n and other vola- tile nuitterx^ ahnost without waste of the latter, place " the solu- tion in a small, shallow dish, which is to be set within a wide- mouthed jar, this being so cuniiectcd that a current of dried air is drawn over the surface of the solution. The air is drawn through chloride of calcium tubes, one of which is placed before and one beyond the jar containing the solution, so that there can be no backward diffusion of moist air. The jar is closed air- tight by a stopper admitting entrance and discharge tubes, the entrance tube reaching nearly to the surface of the benzin solu- tion. The air is drawn at the tlesired rate by an aspirator, one acting by the discharge of water froni a large closed bottle or jar. '• References Uj publication of Dragendorff's work are given on ii. 407. This outline is by no means a substitute for Dr. Dragendorff's book on the chemistr/ and analysis of plants. Hut the outline of his plan of .separations is presented for the convenience of a couipact form, and as .suj,'gestion for instituting various analytical operations on vegetable tissues. -This method of evaporation in a iiirrent of dry air was used by OsSE, who reports control-analyses Ijy il, 187 1064. Selmi, chietiy about 1878 : On toxicology, 1876, Gazzetta chim. ital., 4, 1 ; Joiur. Chem. Hoc, 27, 607. On alkaloids of cada- veric putrefactions, 1873 to 1880 : Ber. d. cliein. Ges., 6, 142; 8, 1198; 9, 195; 11, 808, 1838; 12, 279; 13, 206. " Sulle Ptomaine ad alkaloid! cadaverici," Bologna, 1878. On alkaloids in the cadaver, 1879, Gazzetta chim. itah, 9, 35; Jon.r. Chem. 80c. , 36, 734. On a puisonous alkaloid from a cadaver containing arsenic, 1879 : Gdzzettn chim. ital., 9, 33; Jovn'. Chem. S(je., 36, 734. On an alkaloid found in the brain and liver, and in the wild poppy, 1876, Gdzzetta chim. ital., 5, 398 ; Jour. Chem. Soc, 29, 938. On pathological bases, 1881, Gazzetta chiui. ital., 1881, 546; ■Jour. Cliem. Soc, 42, 741. Tii. nusEM.\xN, 1881: The ptomaines in toxicoloirv, Archiv der Phar. [3] 16, 415 ; Am. .lour. Phar.. 54, \U'l. H. Beckurts, 1882 : Distinctions between cadaver and plant al- kaloids, Archiv tier Phar. [3] 17, 104; Am. Joar. Phar., 54, 221. Zeitsch. anal. Chem., 24, 485. Reouakdbl and Boutmy, 1881: Distinctive reacfidiis of pto- maines, Ber. d. chem. Ges.. 14, 1293; Compt. rend., 92, 1056. J\Iarino-Zdco, 18W4 : Ptomaines in toxicolngy, Gazzetta chim. ital., 13, 431, 441 ; Jon.r. Chem. Soc, 46, '.342, 343. Arnold, 1884: Ptomaines in toxicology, yl/vj/z/vj der Phar. \2,'\ 21, 435 ; Jovr. Chem. Soc, 46, 4(i',»". Gaenier, ls,s3 : Ptomaines in toxicology. Jour, dd Phar., 7, 377 ; Am. Joar. Phar., 55, 404. L. Briegee, Berlin, 1884-S7: " Ucher Ptomaine," Berlin, 1885. 430 PYROGALLOL. Zeitsch. physiolog. Chem., 3, 135; 9, 1. "Weitere Unter- suchungen iiber Ptomaine," Berlin, 1SS5-86. Ber. d. chem. Ges., 17, 27-±l ; Zeitsch. anal. Chem., 24, iSi. A new pto- maine producing tetanus, Ber. d. chem. Ges., 19, 3119 ; Jour. Chem. Soc, S2, 284. Maas and others, 188i: Ptomaines in boiled meat, Chem. Cent., 1884, 975 ; Jour. Chem. Soc, 48, 676. V. C. Vaughan, 1884-85 : A ptomaine from poisonous cheese, Zeitsch. physiolog. Chem., 10, 146; Jour. Chem. Soc, 50, 373. Michigan State Board of Health Reports. (See " Ty- rotoxicon,'' in this work.) CoppoLi, 1885 : Ptomaines formed by processes of analysis of tissues for poisons, Gazzetta chim. ital., 14, 124, 571; Jour. Chem. Soc, 48, 278, 913. Gatjtiee, 1885-86 : Leucomaines, Bull. Soc. Chim., 43, 158 ; Jour. Chem. Soc, 48, 676. On alkaloids of bacterial origin, etc., Paris, 1886. Ptomaines and Leucomaines, 1886, Jour. Phar. [5] 13, 354; Jotir. Chem. /S'dc, 50, 634. Ladenbueg, 1885: Ber. d. chem. Gex., 18, 2956, 8100. Oliveei, 1886 : Supposed ptomaines of cholera, Gazzetta chim. ital., 16, 256 ; Jour. Chem. Soc, 50, 1049. PURPURINE. See Coloring Mateeials, p. 190. PURPUROGALLIN. See p. 431. PYROGALLOL. CeHgOg = C6H3(OH)3 = 126. Pyro- gallic Acid. — Manufactured from gallic acid or from gallotan- nin by sublimation. One part of gallic acid with two parts of powdered pumice stone may be heated to 210°-220°C. in a stream of carbon dioxide. To obtain colorless, sublimed in a vacuum at 210° C. Used as a reducing agent in photography ; also to a limited extent in hair dyes, either by itself or to reduce silver. Pyrogallol is identified by its reactions with alkalies and iron salts, and its formation of purpurogallin. \\ \a se])arated ixovx tannic acid by its not precipitating with gelatin. It may be estimated in a lead compound. Pyrogallol crystallizes in lustrous plates or needles of white or yellowish-white color, a very bitter taste, without odor, and a neutral or very feebly acidulous reaction. It gives a brown color to the skin. The crystals are changeless in dry, pure air, dark- ening in ammoniacal air. It melts at 115° C, boils at 210° C, PYKOGALLOL. 431 and at about 2ri()"C!. blackens with productiuii of iiietagallic acid. (See Gallic Acid, p. o21.) It dissolves in tliree parts of water, freely in alcohol and in ether, not in absolute chloroform. The watery solution darkens on standing, sooner if heated, quickly coloring by addition of alkalies, with formation of alkali carbonate and acetate, absorption of oxygen taking place to an extent pro- portional to the coloration, which is destroyed by oxalic acid. The alkalies cause reddish-yellow to- red-brown tints ; lime solu- tion, a violet to purple color ; all becoming gradually brown to black. Ferroso- ferric salts, slightly oxidized ferrous salts the better, give a clear blue color. If there be much ferric salt the color soon turns to red, and with ferric suit alone the color is reddish at first. If the very dilute solution of ferric salt and pyrogallol be gradvially treated with ammonia, the colnr changes first from red to blue, and then back to bright red. (The reaction is like that of purpurogallin, given below.) By gradually adding then acetic acid or other organic acid, the blue is first restored, then a red color again appears. Hydrochloric acid and most inorganic acids give at once a red color. The blue color is produced by bicarbr)uates as well as by ammonia,' also by free alkaloids (Schlagdenhauffen). — In presence of gum arable, blood, saliva, and various other organic substances, pyrogallol, in solution, exposed to the air, gradually forms Pt'EPUKOGALLiN, CooIIj^gOg (Steuve). The same product is obtained at once by adding a strong solution of permanganate acidulated with sulphuric acid, rurpurogallin has a red color of much intensity, imparted to solutions, from which it crystallizes in yellow to red needles, and by sublimation is obtained in garnet-red crystals. It is sjjaringly soluble in water, and its solution, with an alkali, gives a transient blue color of great intensity." Pyrogallol is a most forcible reducing agent, promptly re- ducing salts of silver and mercury, and Fehling's solution, and reducing ferric salts in the iron reactions above given. It is ■Jacqubmin, 1874 and 1876-77: Ann. Chim. Phys. [4] 30, 566; Jour. Chem. Soc, 27, 1016; Jonr. Vhem. Soc, 31, 340. A very cliiiite .•-olution of ferric chloride and pyrogallol is used as an indicator, more delicate than litmns, for the estimation of ammonia or of bicarbonates (as in mineral waters). The solution IS made of ecjual volumes of a solution of 5 grains pyrogallol to tlie liter, and a solution of 2 grams I'eri-ic chloride to the liter. It deposits purpu- rogallin, and needs to be filtered from time to time. Of tlie solution 10 o.c. are added to 200 c.c. of water for alkalimetry. ' As to ethers of pyrogallol, and tlieiV color products, see " Watls's Diet.," viii. 1710. Pyrogalloquinone, ibid. 1713. Reaction witli mercuric chloride and alUaloids, ibid. 1709. 43-3 RACE MIC ACID. attacked by nitric acid, with red products. Its dry mixtures with many oxidizing agents are explosive. In aqueous solution, witli alkali, it removes nearly all the oxygen from a confined portion of air. A gravimetric ediiiKttioti may be made by adding to an alcoholic solution of pyrogallol an alcoholic solution of lead acetate, faintly acidulated with acetic acid, quickly washing the precipitate with alcohol, drying on a water-bath, and weighing. PKCeHgOg). : 2CgH303 :: 457 : 252 :: 1 : 0.551-1. QUINAMINE. See Cinchona Alkaloids, p. 92. QUINICINE. See p. 94. QUINIDINE. See p. 154. QUININE. See p. 125. QUINOIDINE. See p. 94. QUINOLINE. See p. 165. QUINOLINE RED. See Coloeing Materials, p. 182. RACEMIC ACID. £[20411406 = 150. Paratartaric Acid. Traubensaure. Separable Inactive Tartaric Acid. — An isomer of tartaric acid, found in some varieties of grapes, and differing from dextrotartaric acid in the form of crystallization, in optical powers, and in its solubilities as free acid and as calcium salt. It crystallizes in the triclinic system, with one molecule of water, becoming anhydrous at 100" 0. It is soluble in about 5 parts of cold water and in 48 parts alcohol of 0.809 speciiic gravity. Its solutionis optically iiKuiive, not rotaliug the plane of polarized liglit, but it is separable into dextrotartaric and levotartaric acids, as follows : When the racemates of two bases, as sodium and ammonium, in mcjlecular proportions, are crystallized from solu- tion together, crystals of a double salt, as [N'alSrH^C^H^Og , are obtained, and these crystals, rectangular prisms, have certain Iieniihedral faces, and are divided into pairs, right and left, by the position of the hemihedral faces. The one crystal of a pair coincides with the reflection of the other from a mirror. When the two kinds of crystals are separated by hand-picking, the one kind is found to be the suit of dextrotartaric acid, identical with ordinary tartaric acid, while tlie other kind is a salt of another SALICYLIC ACID. 433 tartaric acid isomer, whose solution rotates the light plane to the left, and is termed Levotartario Acid, or antitartaric acid. — Eacemic ae'id, free, forms a. precipitate with calcium sulphate solution on standing, and a precipitate with calcium chloride solution quite readily ; also, the calcium precipitate, dissohed by hydrochloric acid, is precipitated again by ammonia (distinc- tions from dextrotartaric acid). RHOEADINE. See Opium Alkaloids, p. 360. RICINOLEIC ACID. See Fats and Oils, pp. 246, 248, 289. RESIN, COMMON, SEPARATION OF. See Fats aito Oils, p. 378. ROSIN OILS. See p. 280. SAFFLOWER RED. See Coloring Materials, p. 191. SAFFRANINS. See p. 183. SALICYLIC ACID.— Salicylsaure. Acide Salicylique. CyHgOg = 138 (monobasic and with alkalies feeblv dibasic). In structure, CgPl^.COgH.On, in which C'Ojl : Oil — 1 : 2, or- tho-hydroxybemoic acid. — There is but one salicylic acid, but it is one of three isomeric hydroxybenzoic acids (or phenol-car- boxylic acids), namely, the ortho, meta, and para compounds, with the respective positions of 1:2, 1:3, and 1 : 4, for COgH : OH. Sources. — Free salicylic acid occurs very sparingly in nature, having been found in the flowers of Spiraea ulmaria, in Viola tricolor and other species of viola, and in the Gloriosa superba of the East Indies. The ethereal salt, salicylate of methyl, CgH4.C02(C;iIo).OI-I, is known as " wintergruen oil." ]\[ethyl salicylate forms the larger part (over 99 per cent., Pettigeew, 1884 ; 90 per cent., Cahouks, 1843) of the oil of gaultlicria, U. S. Ph. ; according to Pettigrew the whole of the "oil of birch," from Betula lenta bark, commonly sold as " wintergreen oil " ; and nearly or quite the whole of the oil of Andromeda Leschenaultii, of abundant growth in Hindostan, and the volatile oil of Jloiio- tropa Hypopitys of northern Europe. It is also found in the oils of several species of Gaultlieria and in oil of Polygala ])auci- fiora ; sometimes in oil of cloves, and in oil from buchu leaves. 434 SALICYLIC ACID. Salicylic acid may be prepared from methyl salicylate by boiling with potassium hydrate solution until the oil is dissolved, and as long as methyl alcohol is given off, and then acidulating with hydrochloric acid, when the salicylic acid precipitates. Since 1874 salicylic acid has been extensively manufactured from carbolic acid by Kolbe's method.' Dry sodium phenol, CgHgONa, is treated with dry COo , at a temperature increased to 180° C. and finally to about 225° C, whereby disodium sali- cylate, CgH^.COglSra.OIs'a, is formed in the retort, and half the phenol taken is distilled over. Small portions of para-lij'- droxybenzoic acid and traces of a phenol-dicarboxylic acid are formed (Ost, 1879). If potash be used instead of soda the pro duct is the para-hydroxybenzoic acid. But impurities of greater proportion in salicylic acid made from carbolic acid probably result from the impurities in the latter, namely, from the cresols homologous with phenol (tlie " cresylic acid" ) present in carbo- lic acid (see Phenol). Each of the three cresols, C^HgO, treated with sodium and carbon dioxide, forms a cresotic acid, CgHgOg. The cresotic acids so formed are sometimes termed the liomo- salicylic acids, and are direct homologues of salicylic acid, hav- ing the rational formula, GgH3(CH3) . COgH . OH, with the posi- tions CO,H : OH : CHg = respectively 1 : 2 : 3, and 1 : 2 : 4, and 1:2": 5." ' Concerning recent naaniifacture of salicylic acid through formation of diphenyl carbonate, at the worlfs of Aktien (late Schering) in Berlin, see Jahr. chem. Tech., 1884, 504; Hentsohell, Jimr. prakl. Chem., 27, 89, and Jour. Soc. Chem. Iml., 3, 115, 646. '' These three cresotic acids are but three isomers among ten known isome- ric hydroxytoluic acids (or cresol-carboxylic acids) obtained from various sources. Beilitein.'a Orgnnisch. Ohemie. 1883, p. 1457. In part in " Watts's Diet.," viii. 2023. Concerning certain of these acids and xylene products, Am. Chem. Jour., 3, 424; 4, 186. Concerning three hydroxyxylenic acids, Gunter, 1884: B^r. d. chem. Ges., 17, 1608; Jour. Chem. &c.; 1884, Abs.. 1347. It will be observed that the occurrence of homologues in salicylic acid from coal- tar corresponds to the existence of homologues in carbolic acid and in the benzoles, as follows : 1. Benzene CeHo. Toluene CH,. Xylenes CbHi . 3. Benzoic acid CHsO^. Toluio acids CsHsOj. Xylenic acids CgHi oO j . 2. Phenol CbH^O. Cresols (see p. 394) CHbO. Xylenols CsHioO. 4. Salicylic and two other hydroxybenzoic acids . C7Ha03 . Cresotic and other hy- droxyloluic acids CbHbOj. Hydroxyxylenic acids. . . CsHjoOa. SALICYLIC ACID. 435 The question of the occurrence of tlie hoinologues and iwd- mers of true salicylic acid, in the article made from carbolic acid, is further treated under Impurities (g). At all events, tlie crude sodium salicylate of Kolbe's process is acidulated with hy- drochloric acid, and the resulting crude salicylic acid is purified in various ways, by crystallizations from dilute alcohol or hoi water, by dialysis of the sodium salt, and by tiltration through purified animal charcoal. Dr. Squibb (1877) employed sublima- tion of the acid by heat from steam. For some years the "■ natu- ral salicylic acid " has been manufactured from " wintergreen oil " in this country, for medicinal purposes, with claims for supe- rior purity. — The essential oil of the flowers of Spiraea uliniiria, Saliri/Iol, is tlie aldehyd of salicylic acid. The glucoside iiaii- ciii, the active principle of Salix, readily liberates the correspuud- ing alcohol, saligenin. From all these substances, from indigo, and from coumaric acid, salicylic acid can be obtained by heat- ing with potassium hydrate under suitable conditions, and by other chemical treatment. Salicylic acid is identified by its crystalline form inid physi- cal deportment («), its reaction with ferric salt and with nitric acid, and the odor of its methyl ester {d). From Benzoic acid it is distinguished by the odor of the respective products with so- dium amalgam in presence of water, and with lime by heating when dry [d) ; from Ciniiamic acid by the permanganate oxida- tion of the latter to benzoic aldehyde. It can be t; Salicylate of Sodium, p. 445 ; other salicylates, p. 437. a. — Salii-.ylic acid is furnished, according to its grade, in fine, needle-shaped crystals, or in a loose or granular] 10 wder, obscure- ly crystalline or nearly amorphous. White wlien pure, it is fre- quently blemished with a yellowish, or pinkish, or Ijrowiiish tinge. The dinlyzed acid is said to kee]) perfectly white. The " recrystallized '' acid is a good pharmacopieial brand ; tiie " pre- cipitated " acid is of a lower grade ; the " sublimed '' acid is said 436 SALICYLIC ACID. to acquire color and carbolic odor. The crystals are monoclinic (Maeignac, 1855). From moderately warm aqueous solution it is obtained in four-sided prisms, from hot aqueous solution in needles, from alcoholic solution by spontaneous evaporation in large four-sided columns, from a drop of ether-solution evapo- rated on a glass slide in star form or feathery groups of radiate needles requiring to be magnitied 50 to 100 diameters (Hagee). — Sp. gr. l.iS3 at medium temp., taking water at i° C. as 1 (ScHEOEDEE, 1879). I'eruianent in the air. Melts at 156° C. (312°F.) (HuBNBE, 1S72; Kohleb, 1879). Sublimes unaltered by heat from steam at 60 to 8U lbs. pressure, not above 145° C. (293° F.), the product having no carbolic odor (Squibb, 1883). Suddenly heated, at '2L^O°-'i30° C. (l:28°-446° F.). it is resolved into phenol and carbon dioxide, leaving no residue, and when sublimed without care the sublimate is contaminated with phe- nol and gives a carbolic odor In boiling its aqueous solution it vaporizes unaltered with the steam. Heated with concentrated hydrochloric or dilute sulphuric acid, under pressure, at 1-10°- 150° C, it is dissociated into phenol and carbon dioxide. Alkali salicylates oxidize readily. 5. — Pure salicylic acid is odorless and has a sweetish, acidu- lous, acrid taste. The acid of commerce sometimes has the odor •of phenol or of cinnamic acid. Salicylic acid is not caustic, but is somewhat irritant to mucous surfaces, the more so by inhala- tion in dust. It is medicinal in ordinary doses of 10 to 60 grains. If more than 150 grains be given witliin twenty-four hours some disturbance iisually follows. The alkali salic^dates have the effect of the acid, as does also methyl salicylate (Gaultheria oil) (H C. Wood and H., ls86). In hypodermic injections about 0.2 per cent., or the strength of a cold saturated aqueous solution of the acid, is emploj^ed. For external application 1 to 10 per cent, solutions are used. Salicylic acid is removed from the system with moderate rapidity, most largely by the urine, in part by the bile, and in traces by the saliva^ Gaultheria oil becomes free salicylic acid in the living body (Wood, ISsfi : Ther. Ga- zette, 10. 73). In the urine salicylic acid is excreted as salicyluric acid, with unchanged salicylic acid Other reported excretory products are phenol, salicin, and indican. — Salicylic acid, in proportion of about 0.1 per cent. (\ grain to the fluid- ounce), preserves ordinary vegetable infusions. For fruit juices, cider, etc., 0.1 15 to 0.3 per cent, is requisite, but 0.01 to 0.02 per cent, exerts a degree of conserving power. To preserve hypodermic and alkaloidal solutions Dr. Squibb uses the full or half strength SALICYLIC ACID. 437 of a cold water saturated solution (0.2 or 0.3^) . ' As an antizymotic, or antiseptic, the salicylates have much less power than the free acid, and a sufKcient quantity of bisulphate of potassium may be added to complex liquids, with salicylic acid, to prevent its cojii- bination with the bases of acetates, etc. The use of salicylic acid in foods has been forbidden in some countries. c. — Salicylic acid is sparingly soluble in water : at 15° f !. (59° F.) it requires 444 parts ; at 20° C. (68° F.). 370 parts ; at 30° C. (86° F.), 256 parts; at 100° C. (212° F.), 13 parts (Boue- GOiN, 1879). Heated with water under pressure, the acid dis- solves water and liquefies (Ai.exejeff, 1883). In alcohol of 90^ it dissolves in 2.4 parts at 15° C. (59° F.) ; in absolute alcohol, in 2 parts at 15° C. It dissolves, at 15° (_;. (59° F. ), in 2 parts of ether, in 3.5 parts of amyl alcohol, freely in methyl alcohol, in 80 parts of benzene, in 80 parts of chloroform, in 60 parts of glycerin, and in about 60 parts of ordinary fixed oils. It dissolves in carbon disulphide and in volatile oils." Salicylic acid has an acid reaction ; it causes effervescence from carbonates ; it forms moderately stable monobasic or normal salts (as CgH4.CO2Na.OH), those of the alkali metals being neutral to litmus (when pure), and instable dibasic salts (as CgH4.CO2Na.ONa) of alkaline reaction. For conserving certain alkaloids the salicylate is a very favorable salt. Of the normal salts, those of alkalies, calcium, barium, magnesium, zinc, and copper dissolve in water, the lead salt in hot water, but the silver salt does not readily dissolve. The basic salts of non- alkali metals are not soluble in water. Salicylate of quinine, ^■2.^z^'f^2-^T^^?,V^':f^)^ is neutral and soluble in 900 parts of cold water or 20 parts of alcohol; salicylate of atroj^ine is neutral and very soluble in water. — With the alkali salts of the weaker acids salicylic acid dissolves freely in water, making comparatively concentrated solutions, which, however, are really solutions of salicylates. Bcjrax, acetate of ])otassium, and acetate of ammonium are used, also alkali phosphates and citrates, with water, as solvents. With borax a crystallizable union is obtained, NaCyllgOg -f 07115(60)03, of acid reaction. With half its ' RoBiNET and Pellet, 1882: Compt. rend., 94, 1322; Jour. Ghem. Sue, 42, 1010. Bersch, 1H82: " Biedermaim's Centralblatt," p. 340; Jour. C/tein. Soc, 42, 1010. Heinzblmann, 1884: "Biedermann's Centralblatt," p. 503; Jour. Ghem. Soc, 46, 764. " Hager's Phar. Praxis," Brganzungsband, 43. Squibb's Ephfmeris, 1882-85: i, 414; 2, 833. 'Langbbok (1884) reports widely varying solubilities of salicylic acid in different essential oils, and uses this diircrcnue to dislinguish volatile oils from each other: Repert. anal. Chem., 12, 177; Jour. Soc. V/tem. Ind., 3, 547. 438 SALICYLIC ACID. weight of borax, and 'i\ times its weiglit of glycerin, a 25 per cent, solution of salicj^lic acid may be obtained. The combina- tion with boric acid, borosalicylic acid, C7Hg(B0)03.C7He03, is soluble in 200 parts of cold water (Hagee). Glycerin sali- cylate can be formed (Gottig, 1877). — Solutions of salicylic acid and its salts are not easily preserved, and acquire color by standing. d — The stronger acids precipitate salicylic acid from solu- tions of its salts in less than 200 to 400 parts of water. Silver nitrate solution, with solutions of salicylates, not with solntion of salicylic acid, forms a white precipitate of silver salicylate, CylTgAgOg, dissolved by boiling water, also by nitric acid and alcohol. Ferric chloride solution, with solutions of salicylic acid or its salts, gives (according to dilution) a violet-blue to violet-red color of great intensity. The alcoholic solution of free acid is most favorable. A little less delicate than the sul- phocj'anide reaction (E. F. S.mith, 1880), it reveals salicylic acid diluted to 100000 parts (Almen, 1878). The reaction is pre- vented by alkalies, and hindered by alkali acetates, phosphates, borates, potassium iodide, and by oxalic, tartaric, citric, plios- phoric, and arsenic acids, not by dilute acetic, boracic, sulphuric, or nitric acid, nor by glycerin, alcohol, ether, common salt, or nitre (Hagee, 1880). The ferric violet reaction is given by sali- cyluric acid and oil of spiraea, not by para or by meta oxyben- zoic acid; and red to blue ferric colors are given by bromo and nitro salicylic acids and salicyl-sulplionic acid. (See Car- bolic acid, ferric reaction.) — Bromine water gives a crystalline precipitate, CyH^BrgOg, very sliglitly soluble in water, freeiy soluble in alcohol. Solution in 40000 parts of water gives crystals seen under the microscope (Al:me,n, 1878). — Nitric acid, if concentrated, in the cold, and if dilute, by warming, forms nitro-salicylic acids, then by more intense action forms nitro- phenic (picric; acids, the latter recognized by its intense red- brown color. The reaction is most promptly obtained l)y Mil- Ion's reagent, fuming acid mercuric nitrate, and gives coh.ir in dilution with 1000000 parts of water (Almen, 1878). — Copper sulphate, with neutral solution of salicylate, gives a green color. — Glucose with from two to three times its weight of salicylic acid, the mixture warmed with excess of sulphuric acid (concen- trated), gives a fine blood-red color. Nearly the same color is given by benzoic acid in this test ; a brown to blood- red color by hippuric acid (Phipson, 1873). — Sodium amalgam, warmed in a sliglitly acidulated solution, gradually reduces salicylic acid to SALICYLIC ACID. 439 its aldehyde, oil of spiraea, C6H.4.COI-I.Ori, recognized by its odor (compare with Benzoic acid). — A mixture of equal volumes of sulphuric acid and methyl alcohol, distilled from a small portion of residue containing salicylic acid or salicylate, yields a, distillate odorous of wintergreen oil, methyl salicylate, ■CH3.C7II5O3. Ethyl salicylate, formed in a corresponding way, has a similar odor. — Heated with lime, salicylic acid gives the odor of phenol, obtained also by heating salicylates alone (see a). Salicylic acid reduces permanganate of potassium solution, but does not reduce potassium cupric tartrate. — Sulphuric acid, not diluted, in contact with salicylic acid at a gentle heat, pro- duces salicyl-sulphonic «c^/ (Kemsen, 1875), CeH3(S03H) . OH . COgH = C^HeSOg , a quite stable acid, forming both mon(jbasic and dibasic metalhc salts, all soluble in water, mostly insoluble in alcohol. e. — Separation. — (1) Evaporation on the common water-bath carries away free salicylic acid, and is inapplicable to its aqueous solutions. To prevent waste by evaporation, either bicarbonate of sodium or ammonia- water is added to obtain a permanent. neutral or very slightly alkaline reaction during the concentra- tion. Long evaporation now endangers loss by decomposition. If a dry residue be desired, the choice of ammonia for saturation of the acid has this advantage : if the evaporation be concluded and the residue dried at a gentle heat, the excess of ammonia is expelled. After acidulating the residue the salicylic acid may be separated by suitable solvents, or dissolved to estimate by the colorimetric method. —Alcohol, etlier, chloroform, benzene, etc., may be evaporated or distilled from salicylic acid without its waste. (2) Shaking with chloroform, etlier, amyl alcohol, or benzene is very generally employed to remove salicylic acid from watery solutions. If the acid be not wholly free from combination with all bases, it must be liberated by addition of sufficient acid, preferably dilute sulphuric or phosphoric. The solvent must be applied, in successive portions, as long as a portion, evaporated, responds to the ferric chloride test for salicylic acid. Ether has been much used ; chloroform is preferred by Malenfent (1885) ; ■chloroform or benzene by Dbagendobff (1878). When the sol- vent emulsifies and fails to separate from the watery layer, as may occur, the concentrated aqueous solution (not acidulous) maybe acidified and mixed with about twice its weight of ground gypsum, enough to tate up the liquid, the stiffened mass dried at a low heat, pulverized, the powder shaken with etlier or other 440 SALICYLIC ACID. solvent, the mixture filtered and the residue washed (Cazeneuve, 1879). After evaporation of the solvent, the residi^e, if free from other solids, may be weighed as salicylic acid, or, whether pure or not, dissolved in water and estimated by the colorimetric method. (3) Distillation with water, from acidulous watery solutions, by boiling, has been much used to obtain the salicylic acid in the distillate, for colorimetric estimation. ' Denny found this method ineffective in examination of foods. ^ (4) Dialysis of salicylic acid has been resorted to for its esti- mation in wine and beer, milk, and animal fluids (Mutee, 1876; AuBKY, 1880). Muter recovered from milk 90^ by dialysis. Animal membrane is the best dialytic septum for this pur- pose. In separation from wine, elder, and heer the alcohol may first be removed by evaporation to one-third volume, at 7O°-80° C. (Remont, 1881). After extraction with chloroform or ben- zene, in repeated portions, the residue from evaporation of the solvent may be dissolved in another solvent (as with benzene if chloroform were first used), this solution evaporated, and the residue taken up in hot water to a definite volume in ratio to that of the wine, for colorimetric estimation. Dialysis is some- times used in preliminary treatment. A simple test may be- readily made by shaking 50 c.c. of wine witli 5 c.c. of amyl al- cohol ; after standing the layer of solvent is taken off and diluted with an equal volume of alcohol, then tested with a iew drops of ferric chloride solution for the violet coh.ir (Weigeet, 1880). //; examination of canned fruits Mr. Dennj' used the fol- lowing method : ^ The expressed liquids, with sparing washings, were boiled and filtered through glass wool. To 50 c.c. of the filtrate, acidulated, 5 to 8 c.c. of amyl alcohol were added, the whole shaken, the aniyl alcohol drawn off, diluted with an equal volume of ethyl alcohol, and this liquid tested with ferric chlo- ride. In examination of milk for salicylic acid Remont (1883) takes 20 c.c. of the milk, adds two or three drops of sulphuric acid, and agitates to break up the coagulum, when the mass is shaken with 20 c.c. of ether and set aside in a stoppered tube. 10 c.c. of the ether layer are taken in a test-tube marked at 10 c.c, the ether evaporated, and the residue of butter is boiled with alcohol of 40^ strength, and the liquid, when cold, made ' Arcfiiv der Pharm. [3] 2i, 296; Jour. Chem. Soc, 1884, Abs., 373. ^ Gontribuiions Chem. Lab. Univ. Mich., 1883, 2, 81. "Contributions Chemical Laboratory, Univ. Mich., 1883, p. 80. SALICYLIC ACID. 441 up to 10 e.c. and assumed to contain nearly the salicylic acid in 10 c.c. of the milk. 5 e.c. of the solution are then filtered into a graduated tube for colorimetric estimation. But the colorime- tric standard recommended is one obtained by adding a known quantity of salicylic acid to pure milk — 0.1 to 0.2 gram to the 20 c.c. — in a parallel operation. Pellet (1882) takes 200 c.c. of milk, with 200 c.c. of water, and at 60° C. adds 1 c.c. acetic acid and an excess of mercuric oxide (J c.c. each of acetic acid and mercuric nitrate solution — Girard, 1883). When cold, the whey is filtered out, agitated twice with 100 c.c. of ether, the ether solution washed, passed through a dry iilter, and evapo- rated. The residue is taken up in dilute alcohol for colorimetric estimation. In examination of hutter, 10 to 50 grams may be boiled with alcohol diluted to 40 or 50 per cent, strength, and the fil- tered solution, concentrated to a definite volume, titrated in the colorimetric way. For the detection of salicylic acid in the urine, unless highly colored, it may be tested directly by adding the ferric chloride, in a deep test-tube oljserved from above. Salicyluric Acid (see p. 145) gives the same ferric reaction as salicylic acid. The precipitate of ferric phosphate may be filtered out and more of the reagent added to the filtrate for better result. And if the urine be high-colored, it is to be made alkaline with alkali car- bonate, treated with an excess of lead nitrate solution, shaken strongly, filtered, and the filtrate tested with the ferric chloride. But in most cases the direct test gives the best result (Siebold and Beadbuey, 1881). In 1878 Robinet recommended prepar- ing the urine by precipitation with sufficient lead acetate solu- tion, adding ferric chloride to the filtrate, and then (Pagliani, 1879) adding dilute sulphuric acid, drop by drop, till the red color of ferric acetate just disappears, when the violet test-color will be seen, with least interference from the sulphuric and ace- tic acids. If the filtrate be too dark, basic acetate of lead solu- tion may be used instead of the normal acetate, otherwise re- sults are closer after use of normal acetate.' With 0.002 per cent, of salicylic acid in urine a distinct reaction can just be reached ; with 0.005 p'^r cent, a very distinct color is obtained (Borntrager). _/. — QuantitatiA)e.—^diX\cj\i(i acid in crystals may be weighed 1 Borntrager, 1881: Zeit. anal, dhem., 20, 87; Jour. Chem. Soc, ao, 473. (In the Chem. Soc. Abstract, Bleiessigis given as "impure acetate " of lead in distinction from Bleizucker, "pare lead acetate.") 442 SALICYLIC ACID. s& CyHgOg. Neithcr the free acid nor any of its salts is insolu- ble enough to be precipitated for estimation. The sublimate by carefully limited heat (see a) could be weighed, instead of the crystals. But a colorimetric method by ferric chloride, in com- parison with depth of color from known solution of salicylic acid, was given by L>e. Mijtee, in 1877, as follows : ' The solutions required are . (1) of pure salicylic acid (by dia- lysis and recrystallization) 1 gram in water to make 1000 c.c. ; (2) of ferric chloride such a dilute solution that 1 c.c, treated with 50 c.c. of the standard solution of salicylic acid, just cease to give increase of intensity of color before the last drop or two •of last-named solution is added. — If commercial salicylic acid is to be valued, dissolve 1 gram in water to make 1 liter, and take 50 c.c. in a Nessler tube (or a seven or eight inch test-tube). Of any solution recovered by separation, take 50 c.c, or a quantity to dilute to 50 c.c, in the tube mentioned. Add 1 c.c of the ferric chloride solution to the 50 c.c of the solution to be esti- mated. In one or more tiibes of same width take now, in eacli, 1 c.c. of ferric chloride solution and as many c.c. of the standard solution of salicylic acid as deemed necessary, and dilute to 51 cc After five minutes, or if acetic acid be present after ten minutes, compare the color in the tubes. Repeat the trial with the standard solution until a deptli of tint is obtained the same as that from the solution under estimation. Then, in the trial giving equality of tint, the c.c of the standard salicylic acid so- lution X 0.001 = grams of salicylic acid in the portion taken for estimation. And if the solution under estimation be that of 1 of commercial acid made up to 1000, then c.c. of standard acid X 2 = per cent, desired. Salicylic acid, with ferric chloride, has been proposed (Weiske, 1876) as an indicator in acidimetry. It is much less ■definite than litmus (Mohe, '' Titrirmethode "). The violet color deepens in intensity as the neutral point is approached, but as soon as this point is passed the color pales to reddish-yellow. Apparently the titration of salicylic acid, with volumetric solu- tions of soda, using ferric chloride as an indicator, should give fairly good results, more trustworthy if the volumetric alkali be standardized by a known solution of pure salicylic acid — an ^ solution = 1.38 gram salicylic acid in a liter. Each c.c. of al- kali normal solution ^ 0.138 gram of salicylic acid. g. — Impurities, and tests of purity. — Color may be due to coal-tar compounds, or to iron as ferric salicylate. Carholio ' Analyst, i, 193. SALICYLIC ACID. AAl acid is for medicinal purposes a quite dangerous impurity, but so obvious tliat it is not likely to be neglected by the manu- facturer or tolerated by tlie purchaser, and it is more liable to arise in minute (quantities from decomposition of an article not pure enough to be stable. The cresotio acids (see /Sources, p. 434) are probably the most abundant, and it may be feared the most serious, impurities in the salicylic acid made from car- bolic acid. In lS7y Mr. Williams,' by investigations not (-om- Sleted, reported from 15 to 25 per cent, of " secondary " or al- ed acids, much more soluble than true salicylic acid but leiss soluble than para-hydroxybenzoic acid, in " the best " artiticiaJ salicylic acid of the market. In 1883 Dr. Squibb" said that the better grades of well-crystallized acid of the market con- tained 4 to 5 per cent. " of something which is not salicylic acid " but is inferred to be homologous acid, and " not present in so large a proportion as when Mr. Williams wrote." The liomosalicylic or cresotic acids are described as " deceptively like salicylic acid, " and ''behaving with solvents and rea<^ents almost exactly' like salicylic acid." ' On the contrary, the tw(» isomeric hydroxy benzoic acids are so much moie soluble in water than true salicylic acid that they must be well removed from the recrystallized acid.* Williams and others i-emox u sali- ' Phai: Jour. Trans. [3] 8. 785; Pro. Am. Pharm., 26, 536. ^F/i/icmiri.^, I, 412. « '• Watts's DiLt.."' 3d sup., pp. 584, 2024. ' The following table gives properties, so far as found, for (1) the two isomers of salicylic acid; (3) those of the next homc^logues of salicylic acid which are found to be formed from cresols by Kolbe's method, and have beet termed cresotic acids ; and (8) three reported honiologues removed two places from salicylic acid, or xylenol products, (cjee the foot-note under Sources.) 1. Ilydioxybenzoic acids ; Salicylic acid (onho) . Metahydroxy benzoic. Parahydroxybenzoic . 2. Ilydroxytolu'ic acids : COjIl : on ; fHj = (Creyodc or ** hoiuo- salicyllc acidh "j 1:2: 3 1:2:4 1:2:5 8. Hydrooryxylenic acic^s: E. Gunt'er, 1884. (1). (2l «) Meiting, 150° 200° 210° 160° 178° 151° 170.5° 144° 15.3° Vaporizing. With steam. Not with Bteam, with steam. Not with steam, With steam. flntiil.ili/!/ in water (parts). 444 lOSat 18°t!, 120 at 15° C. Jn alcohol. 2.4 Freely. Easily. In chl&fo- funn . LlUlc Freely. Easily. Ftn-ic reac- tion. Violet. No color. Yellow pre. Violet. No color Blue. No color 444 SALICYLIC ACID. cylic acid from its homologous acids, in a purification of the arti- ficial salicylic acid of the market, by the comparative insolubi- lity of the calcium salicylate, as follows : The acid is treated in boiling water solution with carbonate of calcium in excess, the solution of saHcylate crystaUized by cooling of the filtrate, the salt recrystallized repeatedly, and finally acidified with hydro- chloric acid, to obtain true saHcylic acid. The mother-liquors from the calcium salicylate, acidified with hydrochloric acid, gave the homosalicylic acids, not fully examined. Hydrochlo- ric acid and chlorides are obviously incidental impurities. The pharinacopceia of France (1884) places glycerin among the im- purities, and as falsifications names sugar, starch, silica, calcium sulphate, potassium disulphate, etc. Carholic acid is likely to be revealed by the odor on opening a bottle. Closer examination may be made by warming about a gram (15 grains) in a (dry) test-tube immersed for a quarter of an hour in water a little below boiling temperature, when no odor of carbolic acid should be obtained. Carbolic acid may be separated and concentrated by making a solution with excess of sodium carl)unate and water, shaking with ether, and evaporating the ethereal solution (Ph. Uerm., 1882). A test by the chlo- rate of potassium and hydrochloric acid reaction for phenol, adopted in the IT. S. Ph., 1880, has been said to give a pinkish coloration with the best obtainable medicinal grades of acid (Squibb, 1883). AurfeN (1877) employs chlorinated soda solu- tion and ammonia, avoiding an excess of the chlorinated solution, and adding, last, ammonia to an alkaline reaction — a blue color, red in acidulous and \A\\e in alkaline reaction, reveals l-5000th of phenol at once, l-50000th after twenty -four hours. For organic mcUters, indeterminate, treatment with sulphuric acid, without heat, is official in the U. S. and Uerman pharma- copoeias.' One part of the salicylic acid (0.2 to 0.3 gram) (3 to 5 grains), with 15 parts concentrated sulphuric acid (U. S. Ph.), 6 parts (Ph. Germ.), 6 to 10 parts (Hager), the mixture stand- ing 15 minutes (TJ. S. Ph.), without specification of time (Ph. Germ.), should give no color (U. S. Ph.), should be nearly with- out color (Ph. Germ.), with the 6 to 10 parts of sulphuric acid should give a colorless or pale yellow solution, brown colors indicating insufficient purity (Hager, in " Commentar ''). — For or- ganic matters and iron an evaporation of the alcoholic solution has been pi-escribed by Kolbe (1876, and von Heyden, 1879), and 'This test was advised by Hager in 1876: Phar. Centra/ h., 17, 434; and with additional confidence in 1883 : "Commentar," 194. SALICYLURIC ACID. 445 is official in the phaniiacopcBias, U. S., Br., Germ. "A satu- rated Solution in absolute alcohol, when allowed to evapoi'ate spontaneously in an atmosphere free from dust, should leave a perfectly white crystalline residue, without a trace of color at the points of the crystals (absence of [certain] organic inipui'i- ties ; also of iron) " (U. S. Ph.) Prof. Kolbe directs to dissolve 3 to 5 grams (50 to 75 grains) of the acid ii) the snjuUest possible quantity of absolute alcohol, and pour the clear solution on a watch-glass over a white surface. Mechanical impurities will be perceptible at once. The solution is left to evaporate in an atmosphere free from dust, especially from iron, and crystals in efflorescence are obtained. If points of crystal- borders are brown, resinous, or phenol-like, impurity is indicated ; if light yellow, organic dye ; if violet or pink, iron. Hauer insists that this test is much less trtistworthy than that with concentrated sulphuric acid. — For hydroeldoric acid and chlorides, " a solu- tion in 10 parts of alcohol, mixed witli a few drops of nitric acid, should not become turbid on addition of a few drops of test so- lution of nitrate of silver." — For non-volatile matters test is readily made by vaporization, which should leave no residue. Hager directs to heat 0.15 to 0.2 gram (2 to 3 grains) in a test- tube f inch wide, by moving it through the flame, when at last no stain should be left. In the vaporization odor of phenol is usually developed. Salicyluric Acid — C9HgX04=C6n4.CO.]SrH.CH2.C02H. OH. — Occurs in the urine after administration of salicylic acid (5, p. 436). Crystallizes in fine needles. Melts at 160° C, and de- composes at 170° C, with vaporization of salicylic acid. Sparingly soluble in cold water, easily soluble in alcohol, soluble in ether, less soluble in a mixture of ether and benzene than salic)'lic acid is (Beck, 1876), and thereby separated. Forms stable salts. With ferric chloride gives deep violet color. Salicylate of Sothum.— CgIi4.C().Xa.0K'a.l(H,/))= 38S. — For description and tests of purity see IT. S. Ph., I8S0. Its re- action is not acidulous if it be wholly free from uncondjined salicylic acid. Even when kept in tight bottles, as requiivd, the salt is liable to acquire color b}' storing. According to Hager, this is due to formation of phenol. Hotli the ammonia and the carbon dioxide of tlie air induce decomposition to the extent of giving coloi'. In operating with the salt, traces of iron in filter- paper and in waters must be avoided. Tln^ aqueous solution is instaljle, and darkens on standing. Mr. Martin (liSSI!) states 446 STRYCHNOS ALKALOIDS. that the addition of thiosulphate (hyposulphite) of sodium, 1 part to 128 parts of the salicylate, prevents the coloration of the latter in aqueous solution. — Carbolic acid as an impurity may be recognized by its odor, the better on warming, not above about 90° C. It may be separated for identification by shaking the aqueous solution, exactly neutralized, with ether, and evaporat- ing the latter at ordinary temperature. SALICYLURIC ACID. See p. 445. SANDAL RED. See Coloeing Mattees, pp. 189, 191. STEARIC ACID. See Fats and Oils, p. 240. STRYCHNOS ALKALOIDS.— The alkaloids found in the Strychnos nux-vomica, S. Ignatii, S. colubrina, and Upas Tieute, of the natural order Loganiacese. Strychnine, CgiHo.jNgOg. Pelletiee and Caventou, 1818. p. 447. Brucine, CasHggNgO^. Pelletiee and Caventou, 1819, p. 463. Igasurine. Desnoix, 1853 ; existence called in question by ScniiT- ZENBEEGEE, 1858 : Ann. Chim. Phys. [3] 54, 65. Shen- STONE, 1881 : Jour. Chem. Soc , 39, 453. Constitution of Strychnine and Brucine. — Brucine has the elements of dimethoxy-str^ychnine, C3j^H2o(OCH3)2iSr202. Shen- STONE,' and later Hanssen,^ have shown it well-nigh certain that brucine actually is dimethoxy-strychnine, and are working upon the problem of artificial conversion of the one into the othei'. Hanssen finds the body C^^gHj^gNgOg to be common to both strychnine and brucine, and to be changed by oxidation with sulphuric and chromic acids into Cj^gHj^8]Sf204. The announce- ment of Sonnenschein,' in 1875, that brucine is converted into strychnine by treatment with nitric acid, carbon dioxide being evolved, has not been confirmed, and this conversion is denieil by Haneiot (1884).* The physiological relations of brucine and strychnine have been investigated by Beunton,' with comparison, also, with methyl-strychnine, a product under trial as to its effects. '1883-85: Jour. Chem. Soc, 43, 101; 47, 139; Ber. d. chem. Ges , 17, 2849. •1884-86: Ber. d. chem. 6es., 17, 2849; 18, 777, 1917; 19, 520; Jouv. Chem. Soc., 48, 276. 819, li46; 50, 564. ^F. L. Sonnenschein: Be.r. d. chem. Ges., 8, 212; Jour. Cfiem. Soc, 28, 771. ' Compi. rend., 97, 267; Jour. Chem. Soc, 46, 88. '1885: Jour. Chem. Soc, 47, 148. STRYCHNINE. 447 Yield of Strychnos Alkaloids. — Total alkaloids: 1.65 to 2.8S per cent. (Dragendorff, 1874'). More than is generally supposed, the richest specimens reaching nearly 4 per cent. (Ddnstan and Short, 1883-85, by their own method"). Dr. A. B. Lyoxs, in 1885,' stated the results of twelve specimens, from 2.68 to 4.89 per cent., giving a mean of 3.16 per cent. Of strychnine alone, 0.96 to 1.39 per cent, in the results of a few lots (Deagendoeff, 1874). As a generally accredited statement, from analyses older than the recent methods, strychnine is found in Ignatius bean as high as 1.5 per cent. ; in nux-vomica seeds with an average of 0.5 per cent. The statements of Dunstan and Short are given in foot-note below. Methods of analytical separation of strychnine from br'ucine, in use, are not well assured. Constittvents of Wux-vomioa, other than the Alkaloids. — In combination with the alkaloids, Stryahnio or Igasurio Acid, so named, is in fact an iron-greening tannic acid (Hohn, Arch, der Phar., 202, 137). — A glucoside, Loganin, G^^nfi-^^, was discovered in nux-vomica by Dunstan and Shoet in 1884.' In the seeds of Strychnos nux-vomica, and in pharmaceutical prepa- rations made therefrom, it is present in small proportion : in the pulp of the fruit of Strychnos nux-vomica it was found to the extent of 4 or 5 per cent. Loganin, warmed with sulphuric acid, gives a tine red color, which on standing develops into a purple — a color-result not unusual to glucosides. By boiling with dilute sulphuric acid a glucose and a body named logane- tin were formed. Steychninb. — 0211122^2^^2 = ^34. Crystallizes anhydrous. Constitution, p. 446 ; Yield in nux-vomica, given above. Strychnine is identified by the chemical tests of the fading purple, and the crystallization of the dichromate and free al- kaloid, and by the physiological tests of tetanic effect and bit- terness {h and (^). Microscopic recognition, a and d. Its limits of quantity are indicated by the limit of response in the fading- purple test {d) and in the physiological tests (h). Solubilities, I "4 >i " 5 Good. Play of colors less marked. Paint. Uncertain. " 6 " 7 The solution was evaporated in a common evaporating- dish. Doubtless STRYCHNINE. 453 "WoRMLET ' obtained very satisfactory evidence, by the use of the dichromate, from 0.0000013 gram (0.00002 grain) of strych- nine ; 0.000007 gram giving evidence as satisfactory as could be obtained from any larger quantity, and 0.0000007 gram, when deposited v^itliin a narrow compass, giving a distinct coloration. S. J. Hinsdale (1885) prefers the ceroso eerie oxide as an oxi- dizing agent, and reports a good play of colors from the 0.0000007 gram (0.00001 grain) of the alkaloid. It is to be understood that the limit of delicacy of the color test is wholly dependent upon the concentration of the alkaloid. A barely visible fragment of crystal of strychnine gives a good play of colors, but if dissolved in a few c.c. of alcohol, and the solution evaporated in a common dish, the residue would give probably a negative, possibly an uncertain, result. These statements of the smallest quantity of pure and unmixed alkaloid capable of iden- tification give no answer whatever to the question as to the smallest quantity of the poison, existing in a stomach or a por- tion of food or a plant, capable of rcQOvery and identification. The limits of recovery receive attention, with methods of Sepa- ration, under e, p. 461. Interferences with the color test — (1) Substances diminishing the delicacy of the reaction. Brucine in equal quantity with strychnine prevents the coloration, unless the quantity of each be very minute, less than 0.001 grain, but a mixture of 0001 grain of each gives satisfactory evidence of strychnine (Woem- ley). " The O.Ol grain of strychnine with 0.001 grain of brucine yields a very marked reaction, although somewhat masked " (Ibid.) Morphine is nearly as influential as brucine in dimin- ishing or preventing tlie color test. A residue from a solution of Ol grain each of strychnine and morphine gave Wokmlky ' little indication of the presence of strychnine ; but a similar mix- ture of O.OOl grain of each of these alkaloids gave good evidence of strychnine ; while even a minute quantity of a mixture of three parts morphine to one part of strychnine gave a negative result. — The absence of both these alkaloids, therefore, should be assured, if need be, by use of separative solvents, as directed un- der Separations [e). Of inorganic salts, nitrates and chlorides have been named as diminishing the reaction. Organic matters had the residue from the 0.8 c.c. of No. 6, or even that from the 0.6 c.c. of No. 7, been brought within an area of two or three millimeters diameter, and moist- ened with much less than a drop of sulphuric acid, a good play of colors would have been obtained in trials 6 and 7. ' " Mioro-oheraistry of Poisons," 1885, p. 564. 'I860: CUm. News, i, 243. 454 STRYCHNOS ALKALOIDS. acting as reducing agents undoubtedly hinder or prevent the reaction, and sugar is especially influential in this regard. While it is the rule that the test is to be applied in the absence of sub- stances not alkaloids, in practice it is sometimes diiBcult to be certain whether these matters are present or not. This question can be decided by a control-test as follows : Obtain by itself a narrow film of residue, equal to that tested for the result of analysis, by evaporation of a little of the recovered solution in a porcelain dish by itself. Add thereto (aside from the portions under analysis) say 1 c.c. of a solntion containing in each c.c. from 0.0000025 to 0.000005 gram of strychnine sulpliate (p. 452), and evaporate again. Or evaporate the 1 c.c. toith the small portion of solution under analysis. This residue, with the added known quantity of strychnine, should give a distinct fading-bhie coloration, as distinct as can be obtained by a test upon a residue from 1 c.c. of the strychnine solution unmixed. — (2) Substances giving, in part, the same results obtained from strychnine in the fading-purple test, and presenting the so-called "fallacies"' of this test. The greater number of these substances give a color with sulphuric acid alone, and therefore their results are at once excluded from all indication of strychnine. Among these sub- stances may be named papaverine, thebaine, ci'jptopine, ber- borine, amygdalin, veratrine, and cod-liver oil. Aloin gives a greenish color, fading to yellow. Aniline, colorless with sulphu- ric acid alone, on addii^g the oxidizing agent presents yellowish or greenish tints slowly deepening to blue, which deepens, and (instead of fading) finally becomes blue-black to black. Gelse- mine, colorless alone with sulphuric acid, on adding dichroinate or other oxidizing agent gives a reddisli-pnrple to clierrv-red color, somewhat resembling that of strychnine. Hydrastine, but faintly yellowish with sulphuric acid, on adding the dichromate gives red to green color (Lyons, 1886). Curarine, the non-crys- tallizable principle of worara, obtained from botanical sources allied to those of strychnine, is the only substance besides strych- nine which has been found to give the threefold result of the fading-purple test (Wokmley). — The use of the permanganate, as an oxidizing agent, is more exposed to fallacy than the other oxidizing agents. If the oxidizing agent be mixed witu the sul- phuric acid, and no parallel trial be made with sulphuric acid alone, the reaction of cod liver oil may well be assumed as an indication of strychnine. The physiological test is to be placed second in order of the vabie of evidence. The data for this test with the frog, and the limits of quantity revealed by it, are given under h, p. 4-t9. For STRYCHNINE. 455 the test the alkaloid is obtained in a neutral aqueous solution of a salt, as the sulphate. — The taste of a graded dilute solution gives corroborative proof as to the presence and limit of quantity of strychnine {b, p. 448). — According to WoEMLET, a grain of a l-50000tli solution of the alkaloid unmixed with other matters has a quite perceptible bitter taste ; and a drop of a 1-lOOOOth solution, even in mixture with a very notable quantity of foreign matter, usually has a decided bitter taste. Potassium dichromate solution, added to solutions of strych- nine salts not very dilute, gives a crystalline yellow precipi- tate of strychnine dichromate, (CjjHoolSroOolgHoCroO^ (Ditzlee, 1886), its slow formation being promoted by stirring. The crys- tals include octahedra and often bush-like groups. A drop of the solution, on a glass slide, may be treated with a drop of the dilute reagent, the mixture stirred with a fine pointed glass rod, and from time to time examined under a microscope with a low power. The precipitate is not soluble in excess of the reagent or in quite dilute acids. Solutions of strj'chnine salts in 1000 parts water do not yield an immediate precipitate, but from this a,nd much more dilute solutions crystals can be obtained as di- rected above. The general reagents for alkaloids give precipitates of strych- nine. The precipitate with Mayer's solution, potassium mer- curic iodide, appears in a solution of a salt ol* the alkaloid in 1.5(1000 parts of water. The precipitate by phosphomolyb- date dissolves in ammonia without coloration. The precipitate by iodine in potassium iodide solution is obtained in very di- lute aqueous solutions (1 : 100000), reddish-brown, and soluble in alcohol. From the alcoholic solution somewhat characteristic crystals can be obtained. Alkali hydrates give crystallizable precipitates, soluble in excess only in the instance of ammonia. The ammoniacal solution gives fine crystals of the free alkaloid {a, p. 448). Strychnine is noted, among alkaloids, for its stability under ordinary influences of decomposition. By action of chlorine or broiiiine, monochlorstrychnine or bromstrychnine is readily formed, as a substitutitm compound : by action of iodine, iodated hydriodides are formed, as addition compounds. By treatment with methyl iodide, the salt of methyl-strychnine, C2iri2i(CH3) NgOg. HI, is easily obtained, as also is ethyl-strychnine by the same means. The conversion of strychnine into brucine remains under investigation. See Constitution of strychnos alkaloids, p. 446. 4S6 STRYCHNOS ALKALOIDS. e. — Separations. — Strychnine may be concentrated by evapo- ration of its solutions at 100° C, without loss or decomposition. — - In separation by solvents immiscible with water, chloroform and benzene take it up most abundantly as a free alkaloid (from al- kaline aqueous solutions). — According to Dragendorff, petroleum benzin, though dissolving strychnine but very sparingly, may be profitably used to take it np from alkaline solutions as a means of [qualitative] separation from alkaloids soluble in chloroform or benzene and not soluble in petroleum benzin.' From acidu- lous solutions strychnine is not taken by any of the ordinary sol- vents immiscible with water (except as traces of the aqueous solution itself may be carried in solution with ether, chloroform, and amyl alcohol). From the N'ux-vomica, in total alkaloids. — The method of Messrs. Dunstan and Shoet,^ which has met with general appro- val, is as follows : Of the finely powdered nux- vomica seeds 5 grams are packed in the percolator of a continuous extraction apparatus, and treated actively with 40 c.c. of alcoholic chloro- form containing 25 per cent, of alcohol, until exhausted, which is usually accomplished in two hours or less. The chloroformic solution is agitated (in a separator) with 25 c.c. of a ten per cent, diluted sulphuric acid, the layer of chloroform drawn off and shaken again with 15 c.c. of the diluted acid, and the chloro- form layer drawn off. The formation of the chloroform layer ia much facilitated by orently warming the mixture. The mixed acid solutions should be quite free from undissolved chloroform, and entirely clear. Chloroformic turbidity may be removed by adding a little chloroform and agitating slowly by gradually in- verting the separator. If need be, the mixed acid solutions should be filtered, through a filter wet with the dilute acid, and the filter washed with a very little of the dilute acid. The total acidulous watery solution is now made alkaline with ammonia, and shaken out, in the separator, with 25 c.c. of chloroform. The clear chloroformic layer is slowly drawn off into a weighed or balanced beaker. If not readily obtained clear by subsiding, the chloroformic solution may be run through a small double filter wet with chloroform, washing the filter with a little chloro- form. The chloroform is gently evaporated, a constant weight '' Wormley states that strychnine requires 13500 parts petroleum benzin for solution. Even if this hold good for the alkaloid freshly liberated, it still would require only 0.1 c.c. of the solvent to carry a quantity of the alkaloid easily identified by the color test ' 1883 ; Phar. Jour. Trans. [8] 13, 665. Given here with very slight addi- tions in details. STRYCHNINE. 457 of residue is obtained at 100° C. or on the water-bath, for which one hour is usually enough, and the weight of residue taken, for the qiiantit}- of total alkaloids. From prejhirations of Nux-vomioa, in total alkaloids. — DuNSTAN and Shoet present directions substantially as follows for standardizing an alcoholic percolate of nux-vomi'ca in prepa- ration of a fluid extract of uniform alkaloidal strength.' The operation may be applied to the medicinal tincture or fluid fXt/'(/ct. Take of the liquid 25 c.c, or one fluid-ounce, or other suitable quantity by weight or volume, according to the purpose. Eva- porate nearly to dryness over the water-bath. Treat the residue with water acidulated with sulphuric acid, in the proportion of 30 c.c. of a 7.5 per cent, sulphuric acid for each 6 to 7 grams of nux- vomica represented (1 f. oz. for each 100 grains), adding at the same time, for same quantities, about 7 c.c. (2 fluid- drachms) of chloroform. , Agitate and warm gently. When the chloroformic layer has separated draw it off, add to the aqueous liquid ammonia to cause an alkaline reaction, and agitate with 15 c.c. (or I f. oz.) of chloroform, warming as before. Draw off the chloroformic solution into a weighed dish, evaporate, dry over a water-bath for one hour, cool, and weigh for total alka- loids. — For the Solid ExIrKct the same authors dissolve 10 grains (or 0.6 gram) in ^ f. («. (15 c.c.) of water, with the aid of heat, add 60 grains (4 grams) of sodium carbonate previously dissolv- ed in ^ f. oz. (15 c.c.) of water, and agitate witli \ f. oz. (15 c.c.) of chloroform, warming to obtain a separation. The chlorofor- mic solution of alkaloids is carefully drawn off, and agitated with ^ f. oz. each of diluted sulphuric acid and water (or 30 c.c. of 5 to 7 per cent, sulphuric acid). The clear acidulous watery solution is made alkaline by adding ammonia, and agi- tated with ^ f. oz. (15 c.c.) of cliloroform. Wlien the liquids have separated the chloroform is evaporated off in a weighed dish, the residue dried for an hour over the water-bath and weighed as total alkaloids. — In applying this process to the resi- due from (say 25 c.c. of) the alcoholic preparations, Dr. A. B. Lyons" directs to shake out the acidulous liquid, first, witli two successive portions of ether (25 c.c), then with one portion of a mixture of one volume of chloroform with three volumes of ether, the shaking not to bo too violent. The aqueous liquid made alkaline is extracted by the same etlier-cliloro- ■ 1884: Phar. Jour. Trans. [3] 13. M885: Proc. Mich,. State Phar. Asm., 2, 183. 458 STRYCHNOS ALKALOIDS. form mixture, applying it in two successive portions (30 and 20 c.c.) Separation of Strychnine from Brucine. - (1) By dilute al- ^oJiol of sp. gr. 0.970 (about 21^ weight, 26^ vol.) In 1878' the author communicated results as follows : Solution requires For strychnine, 2617 parts of ^Ifo (weight) alcohol, 500 parts of 39^ alcohol. For brncine, 38 parts of 21j^ (weight) alcohol, 22 parts of 39^ alcohol. When one part each of strychnine and brucine were digested one hour at ordinary temperature with 100 parts of alcohol of sp. gr. 0.970, filtered, and the undissolved alkaloid washed with 100 parts of the same alcohol, the residue of strychnine gave no •qualitative test for brucine, but the brucine left on evaporating the filtrate gave a slight color test for strychnine (even in pre- ■sence of the excess of the brucine). (2) By precipitation with ferrocyanide (Dunstan and Shoet, 1883). The sulphates of the alkaloids in aqueous solu- tion acidified with sulphuric acid are precipitated with potas- sium ferrocyanide. The strychnine is entirely precipitated, both when alone and when in the presence of brucine, while the bni- ■cine is not precipitated unless in concentrated solution. ScHWKit- 8INGEE (1885) did not obtain good results by this method. Separation from Tissues and Foods in analysis for poi- sons. — A weighed quantity (one part) of the material is placed in an evaporating-dish or wide beaker, finely divided under the points of a pair of sharp, bright shears, with moistening if need be to bring to a soft and homogeneous pulp, about an equal ■quantity of water containing about one per cent, of sulphuric acid is added, and the mass digested, with stirring, on the water- bath for 15 minutes. Four or five parts of well-rectified 90j^ al- cohol are added, and the whole digested, with frequent stirring, at a little below the boiling temperature of the alcohol, for about an hour. The edges are to be kept free from dried residue. It is then cooled and strained through close muslin, or filtered through open filter-paper by the help of a filter-pump. The residue is digested, successively, with two smaller portions of alcohol, keeping the reaction of the mass constantly acid, the filtrates from all being received together in a wide mouthed fiask, and the strainers or filters well washed with the alcohol. The filtered liquids are concentrated to a syrupy consistence, with ^Pro. Am. Pharm., 26, 806; Year-book of Phar., 1879, 97. STRYCHNINE. 4?9 occasional gentle rotation of the flask, preventing dried residues on the edges. Four or Ave parts of absolute or nearly abso- lute alcohol are added, the mixture shaken by rotating the Hask, and, when cold, filtered into another flask, and the Alter well washed with the absolute alcohol. The entire tiltrate is evaporated on the water-bath to remove all the alcohol, when about two parts of water are added. If the reaction be rjot sharply acid to litmus, it is made so by adding a drop or two of diluted sulphuric acid. The mixture is Altered, and the resi- due and Alter well washed with small portions of water, re- ceiving the entire tiltrate in a small separator, or strong tube having a good cork. It is now shaken out with chloroform, in one or more portions, or as long as this solvent continues to ex- tract anj'thing. The clear chloroform layer is drawn off by the separator, or forced out of the tube as water is delivered from a wash-bottle, the tubulated stopper fltted for that purpose having an adjustable delivery tulje brought to the conical bottom of the container. Tlie chloroform solution is washed once or twice with a little faintly acidulous water, and the washings added to the aqueous liquid. The chloroform solution is reserved for any tests desired. The a(|neous solution is made distinctly alkaline by adding ammonia, and exhausted by sJiaking out with from three to tive portions of the chloroform. The united cliloro- formic liquids are to be obtai-ned perfectly clear. A zone of par- tial emuIsioTi next to a supernatent watery layer may be resolved bv introducing into the zone a c.c. or so each of fresh chloro- form and of water, and tapping the separator. If need be, the chlorofoi'in so added may be made slightly alcoholic. Also, a little portion of emulsitied chloroform may be washed with chlo- roform on a filter wet with the same solvent. Now an aliquot part of the total chloroformic solution (from the alkaline liquid) may be evaporated for preliminary tests. The residue so ob- tained is usually colored and loaded with substances not alka- loids. Wiien no other alkaloid tiian strychnine is sought, the residue from evaporation of the (remaining) chloroform solution may be purified as follows: The residue is treated with concen- trated sulphuric acid, one or two drops, or only enough to moisten the whole, covered and heated on the water-bath, or, better, heated in an oven at 100° C, avoiding any higher tempe- rature, for an hour or so To the carbonizeil mass, when cold, barium carbonate is added, to neutralize nearly all the acid, still leaving an acid reaction. The little mass is now exhausted with small portions of water, and the solution and washings filtered into a small separator. Tlie ai^u'^ous solution is now nnule alka- 46o STRYCHNOS ALKALOIDS. line bj adding ammonia, and exhausted by repeatedly shaking out with chloroform in small portions. The entire chloroform solution is received in a graduated cylinder, and aliquot parts are evaporated in small porcelain and glass dishes, for the several tests, and for trial as to qualitative limits, also, if desired, for volumetric estimation. The residues will contain some ammo- nium sulphate, the crystals of which are likely to be seen in mi- croscopic examinations. To obtain a portion free from ammo- nium salts and from sulphates in general, treat one of the residues with water and barium carbonate, evaporate to dryness, take up with warm alcohol, filter, and evaporate the alcoholic solution, for another residue. Strychnine may he separated from the Urme by evaporat- ing the acidulated liquid to a syrup, stirring with strong or abso- lute alcohol, filtering and washing well with the same alcoholj concentrating the liltrate to a syrup, which is dissolved in water enough to make a limpid solution. This is washed (while aci- dulous) with chloroform ; then made alkaline by adding ammo- nia, and washed with one or more portions of chloroform. The chloroformic solution is evaporated, either all together or in aliquot portions, for direct tests upon the residue or for further purification, as directed on p. 459. As to the occurrence of sti'ychnine in the urine, following administration, results are stated under b, p. 449. Keivvery from Aleoholio Beverages. — Messrs. Graham and HoFMANN, in 1852, made extensive analyses of the ales ami heer's of Great Britain for strj'chnine, as follows : Half a gallon of the ale was shaken with 2 oz. of animal charcoal, and, after standing 12 to 24 hours, filtered through paper. The drained charcoal was boiled half an hour in purified alcohol, and the fil- tered alcohol distilled off. The watery residue was made alka- line with potassa, and agitated with an ounce of ether [cliloro form]. The residue from evaporation of the ether was tested. Taking | grain of the alkaloid in -|- gallon of the malt liquor, the operators invariably obtained the color test in the final residue. — Probably a preferable procedure would be the treatment directed above for separation from the urine. — With distilled spirits, such as whisky, the same of)eration (last referred to) is advisory, the alcohol being first distilled off, when the slight quantity of resi- due usually renders the op>eration a very simple one. — Single cases of the detection of strychnine in beer in Eastern Europe have been reported. There is no evidence, and no probability, that strychnine has ever been used in the sophistications of dis- tilled spirits. STRYCHNINE. 461 Lunds of Reeovcry from complex organic matter. — From the experiments of Mr. Ivircluiuiier, with the author's co-opera- tion,' it appearetl tluit the limits of analytical 8cparati(,>ii, by a process essentially the same as that just detailed, were as follows : With 50 grams of meat, the loss of strychnine was foi- one part of meat, O.UUOUO 795 part of strychnine; or for one part of the alkaloid, lli5T8t! parts of the tissue-material.' That is to say, in separating strychnine from an avoirdupois pound of tissues the loss of alkaloid is from one thousand to two thousand times the least (quantity needed for certain identification (p. 452). The deposition of strychnine in various organs of the living body receives statement under i, at p. 450. It is capable of recovery from partly decomposed organs some time after death, subject to limitations not yet vei'y definitely established. No other alkaloidal poison resists destruction in the interred body any better than strychnine, probalily none other resists as well. Yet it is by no means indestructible when contained in putrefactive tissue. The data obtained by adding strychnine to tissues, and recu\ering it after some months of putrefactive decomposition, are but imperfectly applicable to cases of poisoning by the al- kaloid, because of the attenuation that results from absorption and elimination. Wormley states " that " the longest period in which the analysis fui'nished positive e\-ideuce of its presence in the exhumed human body is 43 days after death (^-b/;/. (VHyg., issi, 359)." Eut in the case of Magoon, in New Hampshire, 1S75, Drs. Hayes and E. S. Wotid, of B(.)ston, found htryclmine in the body of a woman advanced in years, exhumed one year and three days after death; and the aiudysts reported 0.15 grain in the stomach, 0.23 grain in the liver, and presence of the alka- loid in the intestines. Death had occurred in less than an hour after administration of an unknown quantity of the poi- ' "Control Analyses and Limits of Recovery in Chemical Separations," 1885: Cliem. News, 53, 78. Oontribulions from the Chem. Lab., Univ. of Mich., 2, 91. 'Experiment 4, 5 grams meat, 0.00016 strychnine, good color-test, r,, " " " 0.00013 " faint (i, •' " " 0.00008 •■ very faint" 7, " " " O.0O00G4 " negative " 8, 50 " " 0.0004 " good 0, " " " 0.0002 " faint " 10, " " " 0.00016 " negative " ;!, 5 " bread, 0.0001 " good 4, ' 0.0008 " faint " 5, " " " 0,0006 " very faint" 0, " " " 0.0004 " nr-alivr " »3d ed. "Micro-Cliciri. Poisons," lKnr,. 463 STRYCHNOS ALKALOIDS. son, in a tumbler of hot liquid of extreme bitterness. In 1875 Prof. WoEMLEY made analysis of the stomach and liver seven months after death, and the chemical tests gave no evidence of strychnine, although the final residues had a bitter taste. Death had occurred within two hours, and the symptoms and other proofs were such that there was a conviction for poisoning [Ohio V. Dresbao/i, 1881). Biichner, Gorup-Besanez, Wislicenus, and Ranke (1881) made a series of experiments upon seventeen dogs, killed, each, by 0.1 gram of strychnine, and buried from 100 to 330 days before analysis. In no case did the chemical tests show the presence of strychnine, though the physiological test, with frogs, obtained tetanic convulsions, and the residues had a bitter taste. f. — Quantitative. — Strychnine is estimated g rammetrioally by weight of the anhydrous alkaloid, dried at 100° C. A volu- metric estimation (less exact than the gravimetric) is obtained by Mayer's solution, each c.c. of which represents 0.0167 gram of strychnine (2^:5^7 of 334, in grams). The end of the reaction is distinct, and the precipitate settles fairly well in acidulated water, but settles better in a concentrated solution of potassium chloride (Deagendoeff, 1871:), when each c.c. of the entire solu- tion dissolves 0.00216 gram of the precipitate (ibid.) The composition of the precipitate as Cgj^TIggNoOoHIHglg was near- ly sustained by the determinations of mercury and of iodine communicated by the author in 1880." This chemical formula corresponds to 36.47$^ strychnine in the precipitate. Dragendorff gives a gravimetric trial by washing, drying, and weighing the precipitate, whereby there was a loss of only 1.8^ on the basis of this formula. Though more constant than the greater number of alkaloidal iodomercurates, the precipitate is not the most favora- ble form for gravimetric purposes. And in the volumetric de- termination the solution is to be made of 200 parts to 1 of the alkaloid. g.— Tests for Impurities. — " Strychnine should not be red- dened at all, or at most but very faintly, by nitric acid (absence of more than traces of brucine)." May be colored yellowish but not red when rubbed with nitric acid (Ph. Germ.) Not colored by nitric acid (Br. Ph.) — A more strict exclusion of brucine is effected by washing the free alkaloid with dilute alcohol (sp. gr. 0.970) to separate tlie brucine, as described on p. 458, the residue ' Chem. Lab. Univ. Mich. : Am. Chtm. Jour., 2, 297-99; Jour. Chem. Soc, 42, 664. BRUCINE. 463 from evaporation of the filtered dilute alcohol being tested with nitric acid.' Of ten samples of commercial strjcnnine, treated in this way, all but two gave tests for brucine. Beucine, CggUggNoO^ =: 394. Crystallizes with 4H3O, 15.45j^. — For constitution of the alkaloid see p. 446 ; yield in nux- vomica, p. 447. Brucine is identified by its color-tests with nitric acid and other additions, its dichromate precipitate, its crystalline forms, and its physiological effects as a convulsent {^d\. It is distin- guished from sti'ychnine by a negative result in the " fading- purple " test, and the positive reactions with nitric acid, etc. {d). It is separated with strychnine, and from strychnine, as de- scribed on pages 456, 460 ; and is estimated gravimetrically or volumetrically .(/"). a. — Transparent or colorless, oblique, four-sided crystals, or in groups of delicate needles, varied in form according to the solvent and the conditions. The crystals effloresce in dry air, and on the water-bath the alkaloid soon becomes anhydrous. It melts at 151° C. (Blyth, 1878), at 115.5° C. [when anhydrous?] (Guy). It gives a decomposition-sublimate in the " subliming cell " at 150° C. and above (Blyth), at 2(i4° C. (Guy). h. — Brucine is extremely bitter. In effects in general it re- sembles strychnine, but a far greater quantity is required for the same effect!^ T. L. Beunton (1885) found that it is excreted far more rapidly than strychnine, so rapidly that when given by the stomach to animals pure brucine has little effect. Given hypo- dermically it causes death by convulsent action. "Woemley states that the effect of brucine is that of strychnine, with ^^ the intensity. c. — Effloresced brucine dissolves in 850 parts cold or 500 parts boiling water, the crystals being considerably more soluble. Very soluble in alcohol, absolute or aqueous. As to its solubility in certain strengths of dilute alcohol, see page 458. Almost insoluble in ether, soluble in chloroform, benzene, or amyl alcohol. — The ordinary salts of brucine are soluble in water and in alcohol, not in ether. fl, Nitric acid gives a red color with brucine. For the proper intensity the acid should be concentrated, near 1.42 spe- cific gravity, and the alkaloid should be dry and placed over a ' The author and A. D. Smith, 1H"H: Proc. Am. Pharm., 26, 807. 464 STRYCHNOS ALKALOIDS. ■white ground. If the alkaloid be concentrated at one point, and minute in quantity, it may be treated -with less than a drop of the acid, added at the point of a sharp glass rod. On standing, or heating, the color changes to yellowish ; on evaporating to dryness the red color returns in the residue. About 0.0000013 gram (0.00002 grain) is the limit of quantity for distinct colora- tion, with the best concentration. — Sulphuric acid alone applied to the dry alkaloid causes a faint rose color. If in a drop of the rose solution of the concentrated acid a minute fragment of po- tassium nitrate be placed, an orange-red color is obtained. If the concentration be of the best, abowt the 0.00003 gram is suf- ficient for a sensible reaction. — If the dry alkaloid or its salt be treated with a drop or just wet with nitric acid, as above direct- ed, warmed till the color turns to the yellow, then cooled and touched with a drop or less of good solution of stannous chlo- ride, a purple t(.) violet color is obtained. Excess of either the nitric acid or the tin salt is to be avoided. The heating is only necessary to bring out the full delicacy of the reaction. Sodium sulphide solution (by saturating caustic soda solution with HoS) may be used instead of stannous chloride. The i-eaction with tin "salt may l)e recognized with the 0.00001 gram of the alkaloid. Of the three allied color-tests just described, the last is the most characteristic, and the agreement of the three furnishes quite conclusive proof of identity, with distinctions from morphine, narcotine, and other alkaloids. — In the sulphuric acid and di- chromate test made for strychnine, brucine slowly reduces the chromic acid, with colors changing from dull orange to greenish, without the least resemblance to the " fading purple." Froehde's reagent gives a red to yellow color. A solution of brucine in dilute sulphuric acid, touched with very dilute dichromate solution, gives a red cijlor changing to duller tints. Mer- curous nitrate (free from excess of nitric acid) gives a re- action Somewhat like that of nitric acid, but developed only on heating, the color being carmine, and permanent on evaporating to dryness. Solution of a brucine salt, with solution of potassium dichro- mate, yields a yellow crystalline precipitate of brucine chromate, in groups of bent needles, formed in quite dilute solutions, and somewhat characteristic. The precipitate dissolves in nitric acid with a I'cd color. The (jenenil reiujents for alJinloidx give the customary preci- pitates with brucine. ^"ery dilute solutions give the precipitate with iodine in potassium iodide solution. The precipitate form- ed by phosphomolybdate is of an orange tint, dissolving in am- TANNINS. 465 monia to a yellow-green solution. The caustic alJcalies cause u precipitate, gradually becoming crystalline, and somewhat sol- uble in ammonia. The jihijKiological test of brucine, with the frog, is qualita- tivtdy nearly the same as that for strj'clmine (pp. 't54, M9), but a very much larger quantity of brucine is required for the same effect. e. — i^ijxirations. — Brucine may be obtained from an aqueous or other solution by evaporation at 100° C, without loss. — The aqueous solution of its salts may be washed with any of tlie ordinary solvents immiscible with water, its salts not being solu- ble in "these solvents. On making the aqueous liquid alkaline, chloroform or benzene serves well as a solvent, and aniyl alco- hol also takes it up. Petroleum benzin dissolves it to some extent. The separation of brucine with strychnine, from nux-vomica and from its preparations, is described under Strychnine, p. 45(1. The separation from strychnine is given at p. 458. In analysis for poisons, brucine will be obtained with strychnine by the methods detailed at pages 458, 460. y. — Quliere for twenty-four lOurs, with water-washed ether to form a Sdft paste, covering this for six hours, and then expressing. This treatment is re- peated, and the expressed liquids spontaneously evaporated to a syrup, which is spread on glass and dried (I". S. Ph. of 1870, Br, Ph.) Another method requires maceration of the powdered galls in a mixture of 12 parts ether and 3 parts of alcohol of 'd^K. The expressed liquid is washed with a third of its volume of water, and again with a little water, and the aqueous liquid, containing the tannin, is evaporated on the water-bath. ^1 Holder solution of gallotannic acid at 17.5° C. (63.5° F.) contains as follows : Per- Specific gra- Per- Specific gra- Per- Specific gra- cenlage. vity. centage. vity. ce7itaye. vity. 20 1.0824 13 1.05:30 6 1.0242 1'.».5 1.0S03 12.5 1.0510 5.5 1.0222 l'.» 1.0782 12 1.0489 5 1.0201 18.5 l.<>7(;i 11.5 1.0468 4.5 1.0181 18 1.0740 11 1 0447 4 1.0160 17.5 1.0719 10.5 1,0427 3,5 1.0140 17 l.(H]l}8 10 1.0406 3 1.O120 lti.5 1.0677 9.5 1.0386 2.5 1.0100 IC 1.0656 9 1.0365 2 l.(K)80 15.5 1.0635 8.5 1.0345 1.5 l.OoiiO 15 1.0614 8 1.0324 1 1.0040 11.5 i.(»5'j;-'> 7.5 1.0304 0.5 1,0020 14 1.0572 7 1.0283 1.0000 13.5 1.0551 6.5 1.0263 tannin For Hammer's table of specific gravity and percentage o nin, see Fresenius's " Quantitative Analysis." Sumach Tannin. — From the fruit, leaves, and l)ranches of Rhus glabrum, R. coriaria, and other species of Rlius. Stkn- ' "Organ, qual. Analyse.'' Kopenhiigen, 1881. H. 58-61. 478 TANNINS. HOUSE (1861 ') reported it identical with gallotannin. Gijnthee (1871) " found the tannins of Sumach, Myrobalau, and Divi-divi to be nearly the same — all agreeing closely with gallotannin, and not at all with oak-bark tannin. He found them all to yield gallic acids by glucosic fermentation, and pyrogallols by subli- mation, and to react like gallotannin with salts of lead, copper, and iron, with gelatin, antimony tartrate, and permanganate. Lowe (1873'), from examination of Sicilian sumach, H. coria- ria, the variety chiefly used for tanning, declared it to be identi- cal with gallotannin, and found by elementary analysis (as Giin- ther had done) numbers nearly those of digallic acid. Sumach tannin is a tanning material much used, a fact of interest in view of its agreement with gallotannin. Wagner's classification of the latter as a non-tanning agent appears to be opposed by various evidences. Oak-baek Tannin. Quercitannic acid. Quercitannin. Ei- chenrindengerbsaure. From bark of various species of Quer- cus. Found also in Black Tea (Eochledee). Also the tannin of the Elm and the Willow (Johanson, Dorpat, 1875). It is a glucoside, with boiling _dilute sulphuric acid readily breaking up with formation of oak-red, amorphous, and an uncrystallizable sugar, no gallic acid appearing (Geabowski, 1868); gives up water and forms an anhydride (Etti, 1881) ; boiling with caustic alkalies yields a different anhydride (the same). The oak-red is a phlobaphene, found by itself in the oak-bark. It does not yield pyrogallol in sublimation, but when heated with potash it furnishes protocatechuic acid and phloroglucin, the products also being obtained from oak phlobaphene. Oak-bark tannin is freely soluble in water and in alcohol, in ether sparingly soluble. It gives the ink color with the basic ferroso-ferric solutions, and, less intensely, with ferric solutions. It gives precipitates with acetates of lead, copper, and iron, and with gelatin ; is taken up by oxides of lead, copper, and zinc, by rasped hide, and by animal charcoal. It promptly reduces Fehling's solution, or the permanganate, and chlorinated lime and other oxidizing agents act verv promptly upon it. This tannin is the most important of tanning agents, and the methods of the estimating tannin (pp. 468, 473) have been mainly iramed in reference to valuation of oak-bark. At the same time it is one of the least stable of the tannins, and its extraction without notable waste is a task of ' Proc. Roy. Soc, ii, 401. 'Inaug. Dissertation. Dorpat., Zeitsch anal. Chem., lo, 359. ^ Zeitsch. anal. Chem., I2, 128; Jour. Chem. Soc, 27, 171. CINCHOTANNIN. 479 difficulty. Dragendoeff recommends " to extract the bark with alcohol, distil the spirit in partial vacuum, add water, filter quickly, and estimate at once. Lowenthal's method has the preference for this tannin. Cateohutannin. — From Acacia catechu and other East In- dian trees. The catechu, or cutch, of commerce contains 40^ to 5.")''i of tanning material, and furnishes Catechutannic acid and Catechin. I. Cateohutannio acid (Mimotannic acid, Catechin red) is obtained, nearly free from catechin, by treating catechu with cold water. It is precipitated by concentrated sulphuric acid. Boiled with dilute acids it forms a dark -brown, resinous body, mimotannihydroretin (Lowe, 1869). Gives a changeable brownish-green color with ferric salts. Precipitates tartrate of antimony and potassium (Lowe), alkaloids, gelatin, and albumen, and changes animal membrane to leather. Precipitates lead acetate (with red color), dichromate of potassium (brownish-red), and acetate of copper (with a leather color). It reduces silver nitrate and gold chloride. According to Erri (1876), catechuic acid, or, as he terms it, catechin-red (which may be termed a phlobaphene), is the first anhydride of catechin, and is formed from it by drying over sulphuric acid, or by boiling with sodium carbonate solution. C38U340j^g (catechutannic acid) -|- HqO = SCj^gH^gOg (catechin). II. Catechin (Catechuic acid or Taimin- geiiic acid). Dissolved from catechin by boiling water, and ex- tracted by ether from dilute alcoholic or concentrated aqueous solutions, crystallizing in needles (Era, preparation, " Watts's Dictionary," vii. 415). It gives a green color with ferric salts, reduces silver salts, turns purple with concentrated sulphuric acid, and precipitates albumen, but not gelatin, nor alkaloids, nor tartrate of antimony and potassium. Fused with potash it is resolved into protocatechuic acid (C^HgO^) and phloroglucin (CeHsOg). MoRiNTANNiN or morintaunic acid. From Fustic, prepared from ]\lorus tinctoria. Crystallizable, with an intense yellow culor. With ferric salts it gives a greenish precipitate ; witli lead acetate, a yellow precipitate ; with copper sulphate, a yel- lowish-brown precipitate ; with stannous chloride, a yellowish-red precipitate. CiNOHOTANNiN or cincliotannic acid. From cinchona barks, of wliich it forms at the most 3;^ to 4;^. In clear yellow musses, very hygroscopic, and becoming electric when rubbed, soluble in ' "Die Analyse von PflMiizen," u. s. \v., 1883, p. 167. 48o TANNINS. ether, as well as in water iind alcoliol. It readily changes to a red-brown, resinous body, insoluble in water. By hot dilute acids it forms sugar and einchona-red, the latter dissolving in ammonia, this solution being precipitated by acids, also by barium chloride (with a red color) (Rembold, 1867). With aqueous alkalies, in exposure to the air, red solutions are formed. Ferric salts form a green precipitate ; tartrate of antimony and potassium, a gray-yellow precipitate ; and acetate of lead, a clear yellow precipitate. Precipitates arc likewise formed with solu- tions of gelatin, albumen, and starcb. Its Tiatural compounds M'ith cinchona alkaloids are difBcultly soluble in water, but dis- solve easily in acidulated water. On fusing with potassium hydrate, protocatechuic and acetic acids are formed. Caffetannin or cafietannic acid. From coffee (Coffea arabi- ca). In brittle masses, forming a yellow-white powder. But slightly soluble in ether. By bailing with dilute sulphuric acid, or l)y digesting with alkali hydrate solutions in the air, viridic acid is farmed, with a blue-green color. Viridic acid is ideutihed by giving a blue precipitate with lead acetate, and a crimson color with concentrated sulphuric acid (Roohleder, ^«n. Chem. Plrnr., 63, GECH,iMd. ISfiS, 142). By long boiling with potasli, cnffeic acid is formed, and crvstallizes from the neutralized solu- tion (RocHLEDEE, Hi.AsiwETz). Fcrric chloride gives a dark- green C(jlor. In fusion with potassium hydrate, protocatechuic acid and acetic acid are formed. In dry distillation pyrocatecliol is obtained. Tanxin of Tea. Dissolves from tea very sparingly in cold water, and but slowly in boiling water, black tea withholding its tannin from solution much longer than green tea. Complete so- lution requires brisk boiling for half an hour, with two or three successive portions, each of fifty parts of water.' The average quantity may be stated at 11 or 12 per cent, of total tannin in black teas, and 15 or 16 per cent, in green tea, with widely sepa- rated extremes.'' The character of tea tannin has not been well ' Experiments with twelve kinds of tea gave solutions of tlie tannin, which yielded, in tannin percentage of air-dry tea, ;iu average for the twelve, as fol- lows: In steeping 5 minutes, 0.08 per cent.; 10 minutes, 0.55 per cent.; 30 minutes, 1.53 per cent. : 30 minutes, 2.49 per cent., the digestion being done over a water-bath. — Report by the Author, Pliysician and Surgeon, 1880, p. 339. Fuller determinations are reported by Mr, Geisleb in Tables III. and IV. in the article "Teas of Commerce " in this work. ' Dragendorff (1874) reports green tea at 12 and black tea at 9.4 percent. A. H. Allen (1875), as averages, about 20 per cent, in green tea (with great variations), and 10 per cent, in black tea. Edee (1881), green tea, from nine ALDER TANNIN. 481 established. Stenhouse (1861) found a little gallic acid in both green and black teas, but no formation of eitlier sugar or gallic acid by boiling with dilute sulphuric acid. He precipitated the tannin in strong decoction by adding a lialf-vohirae of sulphuric acid. Kochleder (lS47j found Boheic acid (boheatannic acid), giving a brown color with ferric salts, along with iron-bluing tannin. lu black tea he reported finding quercitannic acid.' The tannin of black tea gives a brown with ferric salts, or in alcoholic solution a green color. Green tea in infusion gives a blackish color with ferric salts, or blue-black in alcoholic solu- tion. Tea taunin precipitates alkaloids generally (cinchonine very closely), gelatin, albumen, and lead acetate. Tannin of Hops. Of the hop cones, 3.67^ (Bowman, 1869). Investigated by Etti (1876, 1878) with results as follows : I. Hop TANNIN. Easily soluble in water and in dilute alcohol, not in ether. Acts as a glucoside : G^^-.j^ )i3 (hop tannin) -|- 3H2O ^= C-HgO^ (protocatechuic acid) -f yi^igHgOg (phloroglucin) -(- (\JIj3Og. Easily dissolved by water or dilute alcohol, not by ether. Gives a dark-green color with ferric salts, a dirty green precipitate with copper sulphate, a yellnw precipitate with lead acetate, a reddish-brown color with alkali hydrates, a bi'uwnish- yellow precipitate with lime solution, and a precipitate with albumen, but, unless previously heated, dry, (ju the water bath, does not precipitate gelatin. Reduces alkaline cupper solutions. By heating on the water-bath, is changed to II. Fhlobaphene of Hop [having characteristics of ataiminjand also obtained directly from the hops. According to Etti, a glucuside (CgQH4g( )„-), yield- ing protocatechuic acid, phlorogluciu, and glucose. Tlie Fhlo- baphene dissolves in alcohol and in alkalies, and is precipitated from alkaline solutions by acidulation. It reduces alkaline cop- per solutions. It precipitates gelatin completely. Tannin of Hemlock-Baek. Abies Canadensis. Extensivelj' used as an American tanning material. The bark sometimes yields IS-lifc tannin. Alder tannin. From Alnus glutinosa. With acids does samples, 12.4 percent. ; black tPii, from twenty-five samples, 10.1 per cent. A report by the Author, in IHTli. gave 12 per cent, as the average of twenty kinds of green and black tea. Much higher figures have been given: Wigner, 1^75, 33 per cent, to 45 per cent. But the best present data are those given by Mr. Geisler in the article on " Teas of C'omineree " in this work. ■ The results certainly indicate that the sweating operations in manufacturo of black tea so act upon the tannin as to convert a smaller part into other sub- stances and modify the remainder. 482 TANNINS. not yield sugar (Stenhotjse). From the wood, an iron-greening; from the bark, an iron-bluing tannin. Used for tanning. Chestnut tannin. From species of Castanea. Boiled with dilute sulphuric acid, yields chestnut-red, a phlobaphene or resin- like precipitate of cherry-red color. With ferric chloride gives a deep green color. Does not precipitate tartrate of antimony and potassium. Fused with potash, forms protocatechuic acid, CeH3(OH)20O2H, and phloroglucin, CeH3(OH)3. For other "tannins see I)ragendorff's " Die Analyse von Fflanzen," article 165, pp. 162-168 ; Husemann's " Die Pflan- zenstofEe," by general index ; Jour. Chem. Soc. , Abstracts, etc. Inks. — The black inks and writing fluids in most general use have gallotannin, taken as nutgalls^ and iron as oxidized in the air from ferrous sulphate, as their essential basis. The gallic acid of the galls is quite as serviceable as the tannic acid, in fact both are required, and inks are made with use of tannic and gal- lic acids and iron. The color compound of iron with gallic acid and gallotannin in inks is mostly not in solution, but is in very fine suspension, usually with help of a slightly viscid menstruum, by use of a gum. Besides galls and their products, logwood is next most used in inks, both with galls and without. It con- tains a tannin, as well as the color substance hematoxylin. Logwood and alum or other salt form the basis of purplish inks. Logwood and chromate of potassium make a clear liquid ink that has been much esteemed. Chrome alum has also been used with logwood. Sumach has been used instead of galls. Some of the nutgall inks contain a little acetic acid, added as vinegar. Some of the gallic inks have the addition of sulphindigotic acid or of sodium sulphindigotate (indigo-carmine). Aniline dyes of va- rious colors are used as a part or the whole of the color of black and colored inks.' — Blue inks are made of prussian blue and oxalic acid, or "soluble prussian blue " and a little oxalic acid, also of anilines. Red inks are made of cochineal, or its product, carmine, with ammonia or carbonate of ammonia. Cream of tartar and sodium carbonate are also used as solvents of carmine. Brazil-wood is employed for another class of red inks, and red to violet inks made from aniline dyes have been common. — India ink and China ink consist of finely divided carbon, and are wholly insoluble, but very durable inks of good service for the pen have been made by a suspension of India ink in dilute hy- ' A black ink very highly recommended is made of nigrosine (an aniline black), potassium dichromate. and gelatin. Directions in New Rem., 1883, 12, 37. Modified for copying ink, ihid., 1883, I2, 250 (Aug.) CHEMICAL EXAMINA TION OF WRITINGS. 483 drochloric acid or in potassium hydrate solution. — Cojjijiiuj iiiks are made by addition of glycerin to any ink, the glycerin tak ing the place of an equal volume of water. — All inks containing tannin, logwood, etc., are liable to mould, and essentia) oils are often added as preservatives. Salicylic acid is a good preser- vative, and carbolic acid usually prevents decomposition. — For indelihle inks for marking linen, solution of silver nitrate, with ;i little india ink, has been used. Gold and platinum have been used in the same way, staining by reduction. Aniline niai'kiiig inks are in use. Molybdenum chloride is also taken as the color- ing agent of a marking ink. — Printer s ink is finely divided carbon in mixture with linseed oil, with lesser additions of tur- pentine, resins, etc. — Ileotographic ink is of aniline color (methyl-violet 1, water 7, glycerin 2). — As to the composition of inks, see the article by Prof. Silliman in "JohnsonV Cj'clo- ptedia" ; also " Watts' s Dictionary," iii. 272, viii. 1090; and an Inaugural Dissertation of O. L. Wilson, Univ. ]\Iich., iSbl. le Chemical Examination of Writings, and the disr/iarge of Iiik-Stains. — Such examination may give some indication <.if tl nature of the ink used, and may serve to show whether two pur tions of writing were written by the same ink or not, and at tliu same period of time or not, also whether ink-murks have l)ecu discharged by^ chemical agents. A minute ins])uctiiJii is first made under a magnify ing-glass, or a microscope of a power of not more than ten diameters. Differences of lustre, color, shade, and absorption into the paper are to be noted, and, when lines cross eacli otlier, which lies uppermost. In the cheniicnl treat- ment the reagents most used i\,m, first, a solution of oxalic acid, one part in fifteen parts of water, ami, srcand, hydrochloric acid of 12.5;^. These may be applied by a quill pen through the writ- ing, and the result noted as the reagent dries. Writing with- gallic inks, of not over two days' standing, is discharged by the oxalic acid in one application to a light gray ; when older the ink color resists longer and a deeper gray remains. Logwood ink- writings, under oxalic acid, mostly turn to reddish tints. Aniline ink-marks are not altered by oxalic acid. Alizarin iidv-marks turn bluish. By treatment with the hydrochloric acid (luit warmed), fresh gallic ink-marks, not over one (hiy old, turn yel- low ; older marks, ycllow-gra)'. Logwood iidv- writings turn reddish orreddish-gr;iy ; those i.if alizarin ink turn greenish ; and those of aniline inks, reddish to brownish-gray. Following treatment with acids and drying, moist vapor of annnonia, or blotting-paper wet with solution of annnonia, may be applied. 484 TANNINS. Under this alkali the marks darken again in different degrees and colors, those of logwood inks turning of a dark violet to violet-black. In distingnisliing between ink-marks as to their age, treatment with ammonia solution of ten per cent, is often quite decisive, old ink-marks dissolving away with more diffi- culty. Other reagents employed are dilute sulphuric acid, dilute nitric acid, sulphurous acid solution, sodium hydrate solution, chlorinated lime solution, stannous chloride solution, and stannic chloride solution. The reagent may be absorbed by blotting- paper a few seconds after its application, or allowed to dry. After treatment with ammonia, solution of gallic acid or solution of cupric chloride may be employed. Control-tests, with writ- ings of known inks and ages, shoukl not be neglected. Obviously it may be possible to show that given marks were or were not made with the same inks, when not possible to identify the con- stituents of the inks. The falsification or alteration of writings is undertaken by erasing or by application of bleaching agents. After erasing the spot is often rubbed over with j)()wder of alum or of sanda- rac, or is coated with a little gelatinous sizing. The bleaching agents used are commonly oxalic iicid, citric acid, hydrochloric acid, chlorine-water or chlorinated lime solution, and bisulphite of sodium. In the investigation the sizing material of the paper must be considered, as well as any coloring agents used in its manufacture. Moistened litmus-])aper, or other indicator, may be applied to indicate the presence of fixed acids. Application of ammonia vapor or alcoholic solution of ammonia may restore colors discharged by acids. Tests for iron salts left after dis- charge of iron ink-marks may be made by alcoholic solution of gallic and tannic acids, or by water solution of one of tlie cyanogen reagents. Copper salts may also be tested for. Among other experiments, the application of iodine vapor, over a beaker, has Ijeen resorted to. To reveal faded marks of iron ink the paper may be moistened with solution of potassium sulphocya- nide, and exposed to vapor of hydrochloric acid.' To remove 'ink-stains from white cotton or linen fabrics, solution of oxalic acid or dilute hydrochloric is most used, and does well with stains of nutgall ink. After hydrochloric acid, granulated tin or zinc may be applied to favor reduction and re- moval of iron. For colored cloths of cellulose fibre, and for 1 Further upon the chemical examination of ink writings see Hager's " Un- tersuchungen," ii. 599; and W, Thompson, 1880: Cliem. News, 42, 32. Also " Rogers on Expert Testimony," 1883, p. 183. TA R TA RIC A CID. 48 5 woollens, repeated washings with citric acid may be tried, but some colors will be changed by it. Strong solution of pyro- phosphate of sodium has been employed, and may be used after treatment with tallow. Aniline ink-stains are in some cases removed by strong alcohol acidulated with acetic acid.' TARTARIC ACID. IlgCJI^Oe = C3H3 j [[^q H) =^^'^- Ordinary Tartaric or Dextrotartaric Acid. Wehimnre. — Very widely distributed in fruits and other parts of plauts, chiefly as Sotassium acid tartrate, calcium normal tartrate, and free acid, [anufactured from the grape-wine deposits of acid tartrate by forming calcium tartrate, and transposing this with dilute sul phuric acid. Largely used, as free acid and as acid tartrate of potassium (cream of tartar), in calico printing, and in baking poM'ders, effervescent carbonates, medicinal preparations, etc. The normal tartrate of potassium and sodium, the normal tartrate of potassium, and the basic tartrate of antimony and potassium are in common use. Tartaric acid is distinguished by the form of its crystals, its odor when heated, and its blackening by sulphuric acid («■) ; by its precipitations as potassium acid salt, calcium salt, and lead salt, by Fenton's color test, and by its extent of reducing power ((I). Methods of separation, as a free acid, and from its salts, by solvents and precipitants, are noted in e. It is estimnffil, as free acid or acid tartrate, volumetrically and gravimetrically (/" ) ; in Liquors of Citric and Tartaric Acids, l)y precipitation and titra- tion ; in Tartars, Argdls, and Lees, hy various methods ; in Fruit Juices, from a lead precipitate (p. iSS) ; in pure watery solutions, Ijy specific gravity. Impurities, g. Cream of Turtar and cal- cium tartrate, p. 496. Examination of Cream of Tartar, p. 4'.>S. BaHiifj Poinder.^, constituents, p. 500; valuation, pp. SOl-Tifj-i. a, h. — Dextrotartaric acid is found in cuiumeree in large, liard, fragmcntai-y, permanent, water-white crystals, or in an opaque-white, fine powder. The crystals, ILX'^H^Og, are mo- noclinic, oblique rhombic prisms, hemihedral, the most perfect ones showing two corners truncated on the same side while the two opposite corners are not cut off They are pyro-electi'ic, shining in the dark, after friction. The specific gravity is 1.764. The dry acid melts at 135° C, forming a clear liquid, which at 170" C. is converted into metatartaric acid, deliquescent and un- ' For directions for removal of stains and spots of many kinds see Nno Remedies, Marrli, 1883, ii, 74; Am. Jour. Phar., Dec, 1880, 52, 632; New Remedies, Jan., 1883, 12, 34. 486 TARTARIC ACID. crjstallizable, and at about 200° C. forms anhydrides, some of which do not dissolve readily in water. At a higher tempera- tui'e the mass blackens and evolves vapors with a strong odor of burnt sugar or caramel. Concentrated sulphuric acid dissolves di-y tartaric acid in the cold without color, the mixture chariing when warmed. c. — Tartaric acid is soluhle in less than its weight of cold water, in about three parts of alcohol (of absolute atcohol, four parts — BouEGoiN, 1S78), in 250 parts of absolute ether,' soluble in methyl alcohol and in amyl alcohol, insoluble in chloroform and in benzene. The watei- solution rotates the plane of polar- ized light to the right. Decomposiiion soon occurs in water solution, with a fungoid growth containing nitrogen. The normal tartrates of potassium, sodium, and ammonium, and the acid tartrate of sodium, are freely soluble in water ; the acid tartrates of potassium and ammonium are sparingly !;<_)luble in water; the normal tartrates of non-alkali metals ai'e inpf)]iiMe or only slightly soluble in water, but mostly dissohe in solution of tartaric acid. Tartrates are insoluble in absolute alcohol. Aqueous alkalies dissolve most of the tartrates (those of mercurj', silver, and bismuth being excepted), generally by formation of soluble double tartrates, such as KgFegfC^H^Og^g, a scale prepa- ration of the pharmacopceia. Foi' this I'eason tartaric acid pre- vents the precipitation of salts of ii'on and manj' other hea\y metals by alkalies. Alkali normal tai'trates als(_i hinder the pre- cipitation of lead and barium sulphates, majiganese sulphide, and ferrous ferricyanide.^ Hydrochloric, nitric, and sulphuric acids transpose tartrates. d. — Lime solution, added to free tartaric acid solution until the reaction is alkaline, gives a precipitate without warming (distinction from citric acid, which precipitates only when heat- ed). With a neutral tartrate the precipitation is obtained by adding much of the lime solution or by boiling. Calcium chloride solution is precipitated, not by free tartaric acid, but by neutral tartrates, in solutions not very dilute, and when neither the tartrate nor the lime salt is in large excess. The precipitate, calcium tartrate (see p. 49S), when freely formed is voluminous and amorphous, and dissoh'es in about 1000 parts of cold water, in an excess either of the tartrate or the calcium salt, in acetic acid (distinction from oxalate), and in ammonium M. Nessler, 1879: Zntsch. aval. Cfifmie, i8, 230. ''Spiller, 1858: Jour. C/iem. Soc, lo, 110. TARTARIC ACID. 487 chloride. On standing, or in dilute solutions at its first forma- tion as a delayed precipitate, it assumes a crystalline form, much less easily seen than the amorphous form, and less easil}' dis- solved by any of the solvents above named, hardly soluble by acetic acid. The calcium tartrate precipitate is soluble in cold strong potassa solution (distinction and partial separation from citrate or oxalate) ; the precipitate reappearing when the liquid is heated, and again dissolving as it cools. This reaction is best obtained with the washed calcium tartrate precipitate ; an ex- cess of calcium chloride in the mixture interferes. — Calcium sulphate solution is not precipitated by free tartaric acid (diffe- rence from oxalic acid), but gradually gives a slight precipitate with tartrates (difference from citrates). Solution of potassium acetate, or citrate, precipitates free tartaric acid, as potassium hydrogen tartrate, KHC4H40g. The precipitate forms slowly, in trimetric crystals, which subside, the formation being favored by stirring with a glass rod. The precipitate dissolves in alkalies by formation of normal tartrates. In this test a neutral or alkaline liquid is to be strongly acidu- lated with acetic acid, which does not at all dissolve the precipi- tate. If a free mineral acid be present, only so much the more reagent potassium acetate is to be added. The precipitate is soluble in about 180 parts water at common temperatures and in 15 parts boiling watei", insoluble in alcohol, and not apprecia- bly soluble in fifty per cent, alcohol. Two volumes of ordinary alcohol may be added to one volume of the aqueous solution, with strong acetic acidnlation, to hold other salts in solution. This precipitate is a separation from citric, malic, and oxalic acids, and from salts of many inorganic acids as well. In the latter case care must be taken that the alcohol does not throw down inorganic salts of potassium. Further, see p. 490. Tartaric acid is distinguished from citric acid, in crystal, and the former is detected in a crystalline mixture of the two acids, as follows : ' A solution of 4 grams of dried potassium hydrate in 60 cubic centimeters of water and 30 cubic centimeters of 90 per cent, alcohol is poured upon a glass plate or beaker-bottom to the depth of about 0.(1 centimeter (one-fourth inch). Crystals of the acid under examination are placed, in regular order, three to five centimeters (one to two inches) apart, in this liquid, and left without agitation for two or three hours. The citric acid crystal dissolves slowly but completely and without losing its ' Hager's " Uiitersuchungen," ii. 103. 488 TARTARIC ACID. transparency. The tartaric acid crystal (or the crystal contain- ing tartaric acid) becomes, in a few minutes, opaque white (in a greater or less degree), and continues for hours and days slowh^ to disintegrate without dissolving and with gradual projection of spicate crystals, fibrous and opaque. Solution of lead acetate precipitates free tartaric acid or tartrates, as wliite normal tartrate of lead, very slightly soluble in water, insoluble in alcohol, but slightly soluble in acetic acid, readily soluble in tartaric acid, in ammonia, and in tartrate of ammonium solution, and freely soluble in ammoniacal solution of tartrate of ammonium (distinction from Malate), somewhat soluble in chloride of ammonium. A color test is made, after removal of heavy metals or oxid- izing agents, by adding, to the acid or its alkali salt, a little fer- rous sulphate solution, then a little hydrogen peroxide, or chlo rinated soda solution, or acidulated permanganate solution (the first of these three being the best) — avoiding an excess of the oxidizing agent — lastly an excess of potassiTim or sodium hydrate solution, when a tine violet color gives evidence of the presence of tartaric acid.' Solution of silver nitrate precipitates solutions of normal tartrates (not free tartaric acid) as white argentic tartrate, soluble in ammonia and in nitric acid. On boiling the precipitate turns black, by reduction of silver, some portion of wliicli usually deposits as a mirror-coating on the glass. The reduction to the specular metallic form may be obtained, from even sliglit quan- tities of tartaric acid, as follows : Acidulate the solution with nitric acid, add some excess of silver nitrate solution, filter out any precipitate (not tartrate), and add very dilute ammonia-water to slight alkaline reaction. If a precipitate of silver tartrate appears, add the ammonia till it is nearly all redissolved, filter, heat to near the boiling point for a minute, and set aside in a warm place. (Citric acid does not effect this reduction, or only on long boiling.) Free tartaric acid does not reduce silver from the nitrate. Permanganate of potassium solution is reduced very slowly by free tartaric acid, but quickly by alkaline solution of tar- trates, with precipitation of manganese dioxide, brown (a dis- tinction from Citrates, which reduce permanganate but very slowly, and then form green solution of manganate, more than precipitate of dioxide). — Bichromate of potassium solution is ' Pbnton, 1881: Chem. News, 43, 110; Jour. Chem. Soc, 40, 655; New Remedies, 10, 147. TARTARIC ACID. 489 readily reduced by tartaric acid, with appearance of a green color and slight effervescence. For use of this test in distinction from malic, citric, and succinic acids, see under Malic acid, at c. In the detection of tartaric acid in Citric acid of commerce,. Cailletkt ' directs to take 10 c.c. of saturated dicLromate solu- tion, add 1 gram of the acid to be tested, and stir, not warming. After ten minutes' standing he found pure citric acid to reniam orange -colored ; that with 1 per cent, tartaric acid, coffee-col- ored ; with 5 per cent, tartaric acid, black-brown. Among the products of the oxidation of tartaric acid by permanganate and chromate are formic acid, carbon dioxide, and water, — Cop- per sulphate with potassium hydrate is not i-educed by tartaric acid. — Gold chloride solution is reduced only in solution made alkaline with potassium hydrate, when a black precipitate of aurous chloride is formed. e. — Tartaric acid may be separated from tartrates by adding- its equivalent quantity of sulphuric acid and extracting with alcohol (in wliich most sulphates are insoluble). Free tartaric acid may be taken out of water solutions by agitation with amyl alcohol, which, after standing, is decanted. From the other fruit acids (citric, malic, oxalic), and most inorganic acids, it is best separated by its precipitation as bitartrate (5), also approxi- mately separated by its calcium reactions (^, and in detailed scheme under Malic acid, cV). From tannin and gallic acid as noted under Gallotannin, p. 477. From acids whose lead salts are soluble in water, by treatment with lead acetate, followed by hydrogen suli^hide, etc. f. — Quant'dnliw . — Free tartaric acid, if unnjixed with other acids or salts which neutralize alkalies, may be estimated volume- trically by standard alkali solutions, the point of saturation in normal tartrate being sharply defined by the tint of litmus or by phenol-phthalein. Weighing 0.750 gram, the number of c.c. of decinormal alkali sulution required e(pials the number per cent.. of the acid. Each c.c. of normal ;ilkaH neutralizes 0.075 gnun of acid. — The acid tartrate of jKitassiui/i, obtained by precipitation, as directed below, may also be cx;ictly estimated by acidimetry,. when each c.c. of normal alkali solution required indicates 0.150 gram of tartaric acid. Another way, properly used m some cases but having no advantage if the acid tartrate be pure, is to gradu- ally ignite the dried precipitate of acid tartrate, at a low red heat, ' Jahresb. d. Phar., 1877, .316; from Jour, de Phar. et de Chiin. [4] 25, 573; Zeitsch. anal. Chem., 17, 499. 490 TARTARIC ACID. till vapors no longer rise, cool and treat the charred mass (con- taining all the potassium as carbonate) thoroughly with water and a slight excess of volumetric acid from the burette, boil, and filter, and wash well, and titrate back with volumetric alkali. Each c.c. of normal acid, after deduction of the number of c.c. of corresponding alkali solution used, indicates (the same as when measuring the acid precipitate with alkali) 0.150 gram of tartaric acid in the bitartrate. Much care is needed to avoid loss during ignition. Tartaric acid is capable of estimation volumetricallyby oxidiz- ing agents. A method with use of dichxomate for this purpose has been proposed (compare Citric Acid, c). The use of permanga- nate for titration of tartaric acid in metallic salts has been re- ported by F. W. Claeke, 1881.' The gravimetric determination most generally applicable is that by precipitation as potassium hydrogen tartrate, though this precipitate is more easily and surely treated volumetrically. The reagent is the acetate of potassium, or, if iron or alumi- num be present, citrate of potassium (Waein&ton); and if the tartaric acid is in neutral salts, acetic acid should be added with the acetate (or citric acid with the citrate) to a decided acid reaction, and enough to fully prevent the formation of the freely soluble normal tartrate. In simple mixtures the acetate is better than the citrate, and excess of either is to be avoided. By use of alcohol the precipitate may be made complete, and may be washed without loss. The moist precipitate, just washed volume- trically clean, may be titrated (either with the filter or transfer- red) with standard alkali, as directed above, or, after washing gravimetrically clean and drying at 100° C, the precipitate may be weighed. KliC^H^Oe : HoC^H^Og-l : 0.797. Tlie strength of alcohol, in the precipitation and in the washing, should be at least 50^ by weight, unless some other agent is depended upon to diminish the solubility of the precipitate. If no interference is apprehended the strength may be 60 to 655^." If sulphates ' Am Ghem. Jour., 3, 201. ^ The author has found the precipitate to be washed continuously with 50 per cent, alcohol without weighable loss Fleischer, ,1870: Zeitsoh. anal. Ckem., 9, 331; Am. Ghem., i, 352. using the precipitate for the determination of potassium, finds it insoluble in 50 per cent, alcohol. (If sodium be present, to avoid its precipitation he directs to add aramoniura chloride.) Gassamajor, 1876: Am. Chem., 7. 84, finds that alcohol of about 60 percent, is needed to preserve the precipitate from waste. Strong acidulation with acetic acid has no solvent effect on the precipitate. Warington found tartaric acid to have no solvent power, citric acid a slight solvent power, and hydrochloric acid much solvent power, when applied, in water, to the precipitate. TARTARIC ACID. 491 are present they are liable to be precipitated by tLe alcohol, and will interfere with the gravimetric treatment of tiie precipitate. A sulphate of aluminium, or iron, or any other salt tliat will neutralize an alkali, will interfere likewise with the volumetric treatment ; but a sulphate of calcium, or any salt that does not neutralize an alkali, may be permitted to go into the precipitate if this is to be volumetrically determined. Further, as ascertained by Waeington and applied in his methods, given below, the precipitate is but little soluble in chloride of potassium solu- tion. For determination of tartaric acid in complex Liquors of Citric and Tartaric Acids, occurring in the manufacture of these acids, Waeington ' directs as follows : A quantity of the liquor containing from 2 to 4 grams of tartaric acid, and of 30 to 40 c.c. in volume, is treated with citric acid unless free sul- phuric acid is present, then treated with a saturated solution of normal potassium citrate, added in nieasured quantity drop by drop with constant stirring. If free sulphuric acid is present no precipitate appears until this is satisfied, when the streaks of bitartrate form on the sides of the vessel. An excess of reagent is avoided, and 4 c.c. are enough for the maximum of 4 grams of tartaric acid. If there is a great deal of sulphuric acid, a fine precipitate of potassium sulphate may appear before the precipi- tation of bitartrate. The occurrence of a gelatinous precipitate shows that not enough citric acid was added, and it is l)etter to begin again. After standing twelve hours the precipitate is col- lected on a small filter, preferably a vacuum filter, and washed with two or three small portions of a five per cent, solution of potassium chloride, then with portions of alcohol, successively of 50^, 70^, and 80^ to 90^ strength, till the washings are no longer acid to litmus. The gradual increase of strength of alco- hol, and the previous use of aqueous solution of potassium chlo- ride, are to prevent the precipitation of salts other than the bi- tartrate, such as the gelatinous phosphates of aluminium and iron, which may clog the filter, and some of which nuiy interfere with the titration. The filter and contents are now transferred to a beaker, and the bitarti-ate estimated volumetrically with standard alkali. Warington also gi\'es a method of washing the precipitate only with a saturated solution of bitartrate of potas- ' Pages 977-980 of tlie iniportnnt repni't on tlio analytioal work of Citric and Tartaric Acid Mannfnotnrp, tH75; Jnur. ('hem. Soc, 28, 935-994. Coii- tinued. on Determination of Tarlaric Acid in Ijees, bv Gkos.ikan, 1879: Jour. Chem. Soc, 35, 341; 1883: 43, 334; Jour. Soc. Chem.' Indus , 2, 338. 492 TARTARIC ACID. sium, "till the acidity of the drain-water is no greater than the- acidity of the wash-water," as found volmnetncally. 1 he drained iilter may be weighed, dried, and weighed agam, to hnd the amount of bitartrate solution in the drained filter so that a cor- rection can be made for the bitartrate retamed m the wash- liquid If there be potassium sulphate in the precipitate, it will interfere with use of this wash-liquid by causing a precipi- tation of bitartrate from its solution. _ . . • . ^ The methods of estimation of the total tartaric acid in tartar, argol, and lees, were summarized by WAEmsTON m 1875 es- sentially as follows : A —The tartaric acid of the acid tartrate of potassium is found by acidimetry, or calculated from determination ot the potassium with platinum salt after calcining. The calcium is determined gravimetrically after calcining, and from this is cal- culated the tartaric acid of the neutral calcium tartrate. B.— The calcined tartar is exhausted with water, the dissolved potassium carbonate and the undissolved calcium_ carbonate are separately estimated with standard acid and alkali, and the tar- taric acid is calculated from both the acid tartrate of potassium and the normal tartrate of calcium. C— The tartaric acid of bitartrate is found by acidimetry. Anotlier portion is calcined and the total alkali (including lime) found by alkalimetry. The number of c.c. of alkah for the bitartrate, subtracted from the numl)er of c.c. of corre- sponding acid solution for the ash, leaves the number of c.c. of tills acid required for the lime, that is, the bases in normal tartrates. D. — The whole of the tartaric acid is converted into normal tartrates by exact neutralization with soda, the wliole evaporated to dryness, calcined, the neutralizing power of the ash deter- mined, and the total tartaric acid calculated therefrom. It is an estimation of the carbonates formed in calcining neutral salts. With a pure tartar (having only the bitartrate, the calcium tartrate, color, and sand) any one of these methods will give nearly correct results of total tartaric acid. Methods A, B, and C give the tartaric acid in the bitartrate, as well as the total. Calcium carbonate in the tartar interferes with methods A and B, the carbonate, if not crystalline, being acted upon by the bitar- trate in obtaining a solution in A. Calcium sulphate also causes 1 Jour. CTiem. Soc, 28, 959. TARTARIC ACID. 493 «rror in methods A and B. But methods C and D are trust- worthy iu presence of carbonates and sulphates (unless sulphides are formed by ignition, as they will be if nitrogenous organic matter is present with sulphates). If crystallized carbonate of calcium is present, in method C it must be dissolved with the tartar by adding a measured tjuantity of standard hydrochloric acid, before the acidiuietry, afterward deducting the standard alkali needed to neutralize the hydrochloric acid. In method D, any calcium carbonate must be dissolved by hrst adding enough hydrochloric acid. In any of the four methods the jDre- sence of organic acids other than tartaric, such as malic acid, or acid products of a change in tartaric acid, introduces error. Of the four methods, Warington gives preference to method C, though in presence of carbonates it does not show exactly how nmcii of the total tartaric acid is in the bitartrate. If there be free tartaric acid there must be more than a corresponding quan- tity of normal tartrate, when this method is to be used. Tlie detaila of method are given as folloM's': Five grams of the powdered tartar are heated with a little water, long enough to dissolve any calcium carbonate, and, if presence of crystallized carbonate be apprehended, 5 c.c. of standard hydrochloric acid are added and a covered beaker used. Standard alkali is then added to the extent of about three-fourths of that required for a gO(jd tartar and for the hydrochloric acid, and the liquid is brought to boiling. When cold the titration is finished. From the amount of alkali (minus that required by hydrochloric acid) the tartaric acid in the bitartrate is stated (p. 489). Two grams of the powdered tartar are weighed into a platinum crucible with a well-fitting lid ; the crucible is placed over an argand burner ; heat is applied very gently to dry the mass, and then more strongly, till inflammable gases cease to be evolved, keejjing the heat at low redness or below. The black ash is next removed with water to a beaker, and some excess — 20 c.c. if the tartar is a good one — of normal acid solution is added frnm the burette, rinsing the crucible with the acid and then with water. After l)oiling and filterinij;i'ec of purity can be obtained, upon ordei', from certain manufacturers, while vei'}' little tartar M'itli less than ;3^o calcium tarti-ate appears to be in use in Eu- rcijie or in this country. Tartar with not ovei' 5^ or at most i'\% calcium tartrate, if mit i)ther\vise imperfect, is to be accepted at present as a good article for ordinui'v uses. Ten per cent, of calcium tarti-ate must be about the utmost quantity in legitimate tartars, those, however poorly or cheaply manufactured, not adul- terated by addition. " Crystallized tartar " — that in larger crystals, subsiding in the crystallizing liquid — does not very much differ in purity from the small crystals, the " cream " of the liquid. Tin: di'etiyili of tartui's is their acidity due to acid tar- trate, and is stated in parts per cent, of this salt. According to AVaki.\gton° the best tartars of South Italy have from 91.0^ to 04.7^ of bitartrate ; good ordinary Italian tartars, .sT.Sf/, to 90.3^ ; and \'iuaccia tartars, from T9.0,S to 85.3^. The first named of these, termed Venetian tartars, are the best 0+' those not pre- sented as lime-free tartars. The French tartars do not equal the Venetian. The ad u.lierationtt common in cream of tartar (ground or in crystals) are terra alba, chalk, alum, and tartrate of calcium. Tartaric acid, acid phosphate of calcium, starch or flour, and barium sulphate have been found. Two lots (with :duni or an inert adulterant) adultei'ated with o.xaHc acid wei-e found in ISSG in jS'ew York Of 27 suspected s;im])les, the New York State Board of Ilealth, in 1SS2. found IG to be adulterated, and 5 to contain .3.27^ to 93^ of teri'a alba, of which o samples had over 7nf;. The tartrate of calcium did not exceed l(i.3',t;; in any case.^ J^arge proportions of calcium compotmds have been re- ported by various analysts, and reported in some cases as calcium tartrate. Calcium carbonate is so promptly changed to tartrate in solution of tlie bitartrate tliat it is not unlikely that an addi- tion of some form of calcium carbonate has rejieatedly given rise to an analyst's report of much calcium tartrate.' AVhen the addi- I Hager's Fharm. Praxis, II. 279 (1878). ' Bv calculation from tliu figuic-s in Jour. Cliem. Sue, 28, 958. ''K. G. Love, 1s82: S'lidhtrij Emiinm-, JIarch ;1U, 1882, p. iv. ; The Ami- lyst, 7, 143. *0. V,. Stone, Univ. Mich , 1877: New Jinn., 6, 274— of 12samples, 6 had from 0.1 peri-eiil. to 8 per cent, calcium lartnilc, and 6 did not huve over 6 per cent, of this salt; 2 had 61 and 64 \n-\- cent, of calcium sulphate. LoN(;WELL, Univ. Mich., 1882: PhyH. and Sury., 4, -104 — of 11 sam|iU\-, highest calcium as tartrate, 7,8 per cent.; 4 samples, calcium as carlmnalr, 49.5 to 63.4 per cent. Rieoer, Univ. Mich., 1883, unpublished — of lOsamiilcs, 4 stated with 41.5 to 68.1 per cent, calcium as tartrate. 498 TARTARIC ACID. tion is calcium sulphate, the sulphuric acid would remain and would seldom fail to be reported as sulphate of one base or the other, but the acid of the carbonate amy escape unnoticed in treating with water. Tartrate of calcium, inert in ordinary uses of cream of tartar, is a by-product of value for production of tartaric acid. That it is added to tartars, in proportions several times greater than they can derive from the argol, does not ap- pear to be established by any evidence at the author's hand. The composition of crystallized Tartrate of Calcium is CaC4H40g.4H20. It loses about 17,'^» of its weight on the water-bath, and nearly all its water at 200° C, but it can be esti- mated as carbonate after igniting and treating with ammonium carbonate. It is soluble in about 6000 parts of water at 15° C, and in about 350 parts of boiling water. It is somewhat soluble in ordinary free acids, in solution of tlie bitartrate of potassium, in solution of ammonium chloride, and in cold potassium or sodium hydrate solution. Determination of the Purity and Strength of Cream of Tartar. — Tests for sulphates, chlorides, salts of heavy nietals, and the six per cent, limit of calcium tartrate are given in the U. S. Pharmacopoeia. Free tartaric acid can be tested for, and estimated, by treating the line powder with alcohol, evaporating the alcohol from the'tiltrate, testing for acid, and, if found, esti- mating it volumetrically. In a nitric acid solution of the tartar phosphoric acid may be' tested for witli molybdate. If sulphates are present, the ash, or the thoronghly-charred mass, in hydro- chloric acid solution, should be tested for aluminium, which may be done (in absence of phosphate) by adding ammonium chloride and a slight excess of ammonia- water.' If aluminium be found in any considerable quantity, ammonia may be tested for, as further evidence of alum. Terra alba, or chalk, or other earthy addition will be left undissolved after treatment of the powdered tartar with warm potassium hydrate solution (which, not too hot, dissolves calcium tartrate). The residue, filtered out and washed, is examined for carbonates, sulphates, calcium, barium, silica, etc. Then the operation may be made a quanti- tative one, and the collected residue washed, dried, and weighed. But in case of terra alba (calcium sulphate) alcohol should be add- ed before filtering, and dilute alcohol used in washing. Starchy matters will be shown, after heating in water, by the iodine test. Now, in absence of alum, free tartaric acid, acid phosphate, or other foreign substance that can neutralize an alkali, the strength ' In presence ol the tartrate ammonia does not fully precipitate alumi- nium. ACID TARTRATE OF POTASSIUM. 499 of the tartar, in percentage of hitartrate of potassiuTn, may be found by acidiinetry (p. 489). Weig'binjj; out 4.7 grains of the powder, sixty to eighty c.c. of hot water are added, and normal solution of alkali run in from the burette, with stirring and heat if necessary to dissolve the tartar before the titration is completed, until the lieutral point is indicated by litmus or by phenol- phthalein. The number of c.c. X 4: = the number per cent, of hitartrate. One c.c. of normal alkali equals 0.188 gram of hitartrate. Should the percentage of real tartar be too low, it will be the more necessary to aiudyze the neutral substances making up the complementary percentage. If further work be required, in most cases the calcium, is next to be determined. In absence of alum and of earthy ad- ditions, the total calcium may be estimated (without calcining the tartar) as follows: Five grains of the tartar and 2 grams of anhydrous sodium carbonate are boiled with water and well digested, the mixture filtered, the residue washed, dried, and Aveiglied as calcium carbonate. CaCOg : CaC^H^Og.lHaO-l : 2.6. Or CiaCOg : CaC^H^Og:: 1 : 1.88. The percentaiz:e of crystallized calcium tartrate, added to that of potassium hitartrate, in a legitimate tartar, should give a sum not far from 1()(). When earthy additions or alum have been found it is better to ignite a portion of the tartar. Two or three grams, weiglied, are dried in a covered crucible, and ii;raduallv ignited until vapors cease to rise, when small portions of ammonium nitrate (or potassium nitrate) are added, until by the continued calcina- tion a wliite ash is obtained. This is cooled, exhausted with hot water, washed, with the rinsings, on a filter, and the residue titrated as follows: lioth the filter and the crucible are ]ilaced in a beaker, an excess i.if standard hydi'ochloric acid added from a burette, the liquid heated and brought back to the neutral point with standard alkali. Each c.c. of normal acid solution used (after deiluction of the idkali used) represents 0.05(» gram of calcium carbonate, or O.l.'lO gram of crystallized calcium tartrate, or O.d'Jf gram of anhydrous calcium tartrate. When Cidcinm sulphate is present, some reduction to sulphide will oc- cur in the ignition, and a c.orrespoiiding portion of calcium of reduced snlphate will be iricluded in the estimation. — If there be a residue of the ash insoluble in hydrochloric acid (terra alba, silicious matter), it may be washed, dried and weighed, and after- ward subjected to analysis. 500 TARTARIC ACID. If alum is to be estimated, in absence of other sulphates, it may be easily done by a gravimetric estimation of sulpliuric acid as barium salt, precipitating in a strongly acid solution, and igniting the precipitate in the usual way. To obtain the (quantity of calcium tartrate when other cal- cium salts are present, the powdered tartar may be treated with warm potassium hydrate solution (as directed on p. 498), adding alcohol if there is sulphate, washing the residue on a filter, evaporating the filtrate, first neutralized with hydrochloric acid, and precipitating with oxalate of ammonium in presence of a little free acetic acid.' The precipitate is weighed as carbonate, after ignition. A more complete analysis may be conducted by determining the total tartaric acid Ity Warington's direct method (p. 494), the acidity due to acid tartrate by simple acidimetry, the total calcium soluble from the ash by hydrochloric acid, and the ash not calcium carbonate. Unless irregular constituents are present, the tartaric acid in excess of that in the acid tartrate may be calculated into normal tartrate of calcium, and any excess of calcium beyond that in the calcium tartrate calculated into carbonate or sulphate, or as the qualitative examination indicates. Baking-Powders. — These have so far been presented to the public either as cream nf tartar baking-powders, or without statement of their constituents, or as acid jiliosphate powders (Horsford's). They consist of sodium bicarbonate with an acidi- fying agent, potassium hitartrate, or alum, or tartaric acid, or acid phosphate of calcium. Ordinary carbonate of ammonium has been used, alone, as a baking-powder, and more used for a part with acidifying agents. A proportion of starch or flour, as " tilling," is found in nearly all baking-powders, and is neces- sary to the permanence of tartar and tartaric acid powders. From 13 to 18 per cent, of starch is not too much for the per- manence of a cream of tartar baking-powder, but tilling beyond 20 per cent, must be held an unquestionable dilution." There ' The precipitation of calcium from tartars, a^; an oxalate, is in most oases more trustworthy if done in the preseiice of a little free ,icetie acid. The solu- tion should not be very dilute, and twelve to tweni v-four hours should be given to the precipitation. ■^Dr. E. G. Love, acting for the New York State Board of Health, in 1882 (Sanitary Engineer, .March 30; The. Analyst, 7, 142) found, of 84 baking-pow- ders upon sale, 49 were cream of tartar powders, 3 were tartaric acid powders, 20 were alum powders, 3 were acid phosphate jinwders, 8 contained both cream of tartar and alum, and 1 had alum with acid phosphate. Flour or starch was found in all l)ut 11. jVmmonia was found in 35. [The alum reported in 29 of them was doubtless ammonia alum.] Eight were reported adulterated — six with terra alha, one with tartrate of lime (in the tartar), and one with insoluble calcium phosphate. BA KING-PO J VDERS. 50 1 has been dispute as to the injurious effect of alum baking-pow- ders, but, at ajl events, they are seldom if ever sold to the public with any statement or admission that they contain alum. The ]>roportlon of carbon dioxide extricated on boiling a baking-powder with water is termed its "strength," and is stated in percentage of weight, or in cubic inches (at 60° F., 30 in. bar.) from an avoirdupois ounce. In the case of a cream of tartar powder we have : NaHCOg + KHC^II^Oe = KNa €411406 + CO., + II„0 84: -]-l8s; = 272 -14 " SO.SSf^ 4-ey.l2^ =100.00^ 16.175^ At 60° F. and 30 inches pre.-^sure 46.26 grains of carbon dioxide measure lOO cubic inches ; therefore 16.17 grains measure 34.09 cubic inches. That is to say, 100 grains, of a mixture 30.88^ ab- solute bicarbonate and 69.12^ absolute Ijitartrate, will furnish 16.17 grains or 34.18 cubic inches of the gas. And 1 av. oz. of the same chemically pure mixture will furnish 149.54 cubic inches of the gas. If we have a baking-powder holding, for ex- ample, S4 6.73 2.29 3.43 .82 'noGuoQ aim -vox uomiuo:) pooff u r-i <0 ^ S w w g s s i lO W CO • noduoQ Smtioj^ uoiuiuoQ 1 00 5 3 00 CI -* --O QO CD .-1 QO C^ OJ O CO 04 ■ -noduoQ CD S5 s e s T ^. ^ ^ CO « ci i-i ■TlOduOQ Suzuoj^ mmp9jf[ 1 Oi co CO W -rf CO OJ in CO 00 ■^ lO « « - noduoQ Gmuoj^ iunip9jf CO ai 1-1 ^ If: S S 8 ^ in oj CO • no6uoo GumojY mmpdj^ i 3 ^ M 1- w in S fe 8 ^ in (M* co' 'no3uoo 3muoj^ iump9jfi umj.?dng S3 OS 5? j: g g S lO oi co" ■noOuoQ GmuoM u.oij.ddns CO to o co" oi CO »n cn' oi CO ■p9 o S 8 O QO in ■TfH lO CO CO CO 00 ^ w in T-I CO ID < g {Mpddsuj ],(i0f) tiq pap^C CO ■.-<' 00 cc in ■ {M)p9dSU/ •ijiOQ fiq p9}0dC -3^ ) I 'fiamdmj g s ^ oc ^ : 0* ■ ddpawduriQ 9unfu)jg; uomiuoQ 00 c s s CO CT CO 03 CO ■u.9p(nod -UThQ dunhojq 9U%^ CO s g CO 1- in" cj CO CO CO •uosfi.^ 5unox 9unfioj\[ iS9m^ CO CM o o ^ 03 O CO in CO ■j,?pa}odun^ 9un e JiT 3 o- CD CO o6 p- Ol CO O CD ifi Eemlts of the exami- nations of commer- cial teas obtained direct from impoi^t- ers and wholesale houses. II So, 1.3 1 EH .s 03 B O < o Eh < X c 1 - 'H : *o : £^ G = <^ ^. bfl a) -j; ^ S a; n — 3 ;s: £ 'K '^ oj-u-o ■■ «< 2*; S'^g .^s^ , Q> s +^ 3 P fi a i^ . s - . = |.|8if ' CO a! ,tl — *i CO cj aj i- - a E.S o-xi oi^ .5 S » SJ3 TEAS OF COMMERCE. S07 «5- s s •duopo I^JOrtuy uoiuvioj •buoioo Hoiuy tunipijf ■Buapo osmuMji uo}u^ns •GUOJOQ VSOULIO^ t»^ut^ 6U0100 /iomy uoviuioQ '3uojoo lunuy lu/np^ji; ■buopo ■Buojoo •Guopo v90HiM}ji u g " o M §5- & CD e* CO a 9 J3 gs N (M 10 «t 01 -" O ^ s :?: s in o* m 3 "^ lO CO o S § CO c; T-H i-^ OT o fe S8 3 5 OJ CO -* OS -t< CO Oi O CO o ci CO '6uotoo nsovi.to^ }SKnj; uvwn ■Q '03^ umpuj ■^ '»si/ uvfpuj E 'JW.2; «»?P"/ •5 'B3i UVtpul 3 S CO CO CO S 3 B 8 3 3 e aJ s "* :i: CO CO s in -' CO 5 3 ° s CO e g s « CO o* 00 in w CO »n c* CO 'I 'Ds^j; umpvj £ t i; 5 c 1^ '-' ^ s; 3 ■:~^ C f- * s c8 r-J in ci ; 8 ^ a 5 I 5o8 TEAS OF COMMERCE. pa 'A n Q> tm 1 01 (1< "* lO »o •S9sfi^uy /o -oj^ o CO - =D C- 00 1 B « t- ro CO « g Xi 05 ■pfoy -losui ysy CT CO 1- ^ S =^g "2 «5 -t-j ♦ OS ■ysy DiQnioswj g| g s ^ ^ ^ s s s s s ^ w l-- « (m' c6 -^ ci « co' 1-1 ci oi V^r 'IQmos ^ ^ ^ ^ n S (N s s s s ss CO CO CO CO CO CJ CO CO CO W CO CO ■ysy mox ^ g g CO n ^ 00 C- 00 S g s o iO lO iri CO in id CD CD in m CO CO c 5 in (?* CD t- O I- 00 ■nupyj; CC CO t- oo O T-- CO 'tf' 00 i- CO in CO T-I Ci ©*" CO 1-J (N ci ai T^ oi ci -c -tH t- t- t> CO OO CD 05 Tf T t< Oi CO O 00 t- O 0= CO CO 00 •4_ lA in 1 ■muuvj, CO CO •^' lO P T-'' CO ci CO 00 1- ■I ci J 1-1 1-. " fe lO S( s T-l 00 (- S '£ O W ■tJ< •fvdi diqnpsuj s « B s in -^ i£3 S S O O CD s Oi t 00 i^ (N CO CO OO m OQ tf CO -^ CO cs lO CO CD CO o o ■fmJtxs max in " ^ ^ S ? ^ fe safe CO S E: CO g s s gj 3 « ? s ■pvdfxs Ml /2Dn g fe g -^ 3 S fs S 8 S5 S S Ci GO ^ : OS Oi in in i> •^dnpioj^ m CO 00 O 00 CD CO CO lO iO CD m m ci t-^ 00 ^ ^ e-a „-S O s| o g S8 Ij 3 03 •a 6 Iz; o O o 1 o 1 a E c E H ■a a E 1 f 3 1 1 3 c: i g 9 s M 1 i n bo ■^ 1 > < 03 ii •5 <1 is > < 1 1 TEAS OF COMMERCE. 509 pa ►J 'HoBnoQ Ginu s s s OS s s s s ■OJ^ UOUlUiOJ 01 10 S ■^ s; " Oi ^ -^ 'miDuo,) ^nosw\[ !3 s a s Oi ■•J' s s s s iioiHuioj pooo ■no/jiio.) ?S OS 3 Tjt s (W CO s " S s CD IS /,) ^ CJ Tf< ^ ■6ho]0o in s »n s to e s g CO fiomy uintp^i^ OJ s t- s " CO s " tjaoioo -r te g a s § fi if /Unuy m/np^jf 55 h; CO s so 10 " ?? s - '6110100 VffOUt (J s s s CO to to Qf s m -.10^ .louddns ^ § ss s Oi -s Ct CO s ^ •Guojoo vtfom 0" s s g i2 S Ci 01 § -.lOji /.-''i-wjq,, a s? s s CO s « CO to - •6uo}oo moui s s § s s g s u CO ■M^ (>>-^oio>ij s S5 Oi 10 1* s 0* T t^ ^ ■p9-^M S e s ^ s '6 ^ g s -UDfl ui)dvp 3 s 01 CO 3 (M CO cc -• CO ■p9M^ 10 t- v, Si 10 ^7 00 CO -poifmq undDf ^ ■.19P j^ •r- CO no ■^ S g -aiodunf) ^U7i ¥ 5< "^ Ooj^ uouivj/yf) •^i 3 g a ^: '"' Th IC ■^ Adpniod g s -unf) ?ii!ifu>j^ 10 CO "M""AV i>f^'^i3^ Jo s? CO 1- -^ fe « ■s '^ 8 £; t- 3 s g ^ g ^ v^X uvtpuj 5 S Si g 01 s C( >:*< s r-l 10 s «: 00 3 s s s « ■mj, umpuj « s g 8 s " S CO CO g • '-t ■ ■ tLCO ■ ti] ■ il-lli ■1, , •°a ■^ t : = CJ ■ Prfill '0 bJJ • 1=1 t^ as - & 22 ^11 bo : — (U T3 ^ 1^ H ' 2^ 1- a 1 ■■ ft : fl- P M 1=: I, S - Pi S 3 u «8 s parts watei- at 10n° C. (Dragendorff) ; 4l!S4 pai-ts absolute alco- hol at 17° C, and 42:i parts boiling al)Solute alcohol (Teedmann, 1S78), in 140O jiarts cold alcohol (Mitscueklich, 18.59). It is but very slightly soluble in ether, one ]iart retjuiring 17000 parts cold ether or 600 parts boiling ether (Mitschcrlich). It dissolves in 105 parts boiling chloroform (Trenmann) ; is somewdiat solu- ble in amyl alcfjhol ; but slightly soluble in benzene ; insoluble in petroleum benzin. — Tlieobromine is a weak base. It forms crystallizable salts ; but on contact with water they give up acid and become iiasic salts, and those of volatile acids give up the acid at or below 100° C. Theobromine dissolves in hydrochloric and in other acids; but the hydrochloride, C'-.Il8N4().^. HCl . HoO, and the nitrate, ('YUglSr^Oo. IJNO3, do not dissolve at all freely in water alone without free acid. Theobromine dissolves in ammonia-water. Ticspecting combinations, see report of Messi-s. Schmidt and I'kfsslee, 18S;1' il. — Theobromine responds to Ihe niuru'dui lent with the same intensity as (laffeine (p. 79), forming amidic acid when warmed with hydrochloric acid and potassium chlorate and eva|»i>rated to dryness on the water-bath, and giving purple- colored murexoin when the cold residue is touched with am- monia. — Phosphomolybdate of sodium, added to the acidulous Jyiebig's Annalen, 217, 287; Jour. Chem. Soc, 44, 873. 514 TYROTOXICON. solutions of tlieobromine, gives a yellow precipitate, obtained in dilute solutions. — Platinum chloride does not precipitate, except in concentrated solutions, when crystals are obtained, (CVHgN/).)2llClPtCl6.iH30. In like manner gold chloride yields yellow crystals, in tufts of needles, C^IigX^Og . liCl . AuClg. — When an ammonia solution of tlieobrumiue is treated with silver nitrate solution, a gelatinous precijjitate is ulitained, and on boiling this granular crystals of argentic thet>broiuine are ob- tained, C\H7AgN402. And when this compound is treated with anhydrous methyl iodide, at 100° C, for twenty-four hours, ca'ifeine (methyl theobromine) is formed, with silver iodide (Steeckee, 1861). Again, when theobromine, alcoholic solution of potassium hydrate, and methyl iodide, in equiva- lent quantities, are heated together at 100° C. in sealed tuljes, caffeine is formed, with potassium iodide (Schmidt and Peesslee, 1883), aH„Ag]N'40., + Cll3l = CVIi7(CIi3)N402 + Agl C^HgN/)^ + 0H3l"+ KOk = C7H7(CH3)N403 + Kl + Wff. Potassium mercuric iodide produces no precipitate in the acidu- lous solutions of theobromine, and iodine in potassium iodide solution causes little precipitation (distinctions of caffeine and theobromine from most other alkaloids). e. — Theobromine may be separated from non-volatile mat- ters, in general, by sublimation at a gradually increasing heat beginning at 170° C. From most alkaloids by its slight solubi- lities, and from caffeine l>y its smaller solubilities in benzene (Schmidt), or water, or ether. f. —The quantitdtive estimation of theobromine in cacao is made by Schmidt and Peesslee (1883) as follows : The crushed caca(.) is freed from oil by pressure, half its remaining weight of slaked lime is added, and the mixture is boiled repeatedly with alcohol of 80 per cent, strength. The residue on evapora- tion of the alcohol is reciystallized from the same solvent, and is obtained as a white, crystalline powder. It may be dried at 100° C. and weighed. TROPEINES. See Mideiatic Alkaloids, p. 339. TURKEY-RED OIL. See Fats and Oils, p. 287. TYROTOXICON.—" Cheese Poison:' The putrefactive product obtained in 1885 by Professor Vaughan, and recently TYROTOXICON. 515 xniiouneoil by lilm to be diazubeiizuuc, ( ■qII-.N:N, in cumbiiia- tion with uruls.' a. — Tvrcitiixicoii, obtained from milk pi'dilucts as (Iii'(.'ct- ed mider t\ was found to ai;re(_' \\\i\\ diazoliLMizene Inityi-ate, Cyllj. X.,. C'^I1~( )., , in (•I'ystailiziiin- in ncudles, wliicli n'l'aduall)' decompose in moist air. Potassium diazobeiizi'iR', ( '|;IJ.. N._,. ( )K, obtained fi'om tyrotoxicon,'' aii[n'ared in tine six sidcMl ])lates. Tyrotoxieou compounds, at IdnM'., ex])io(k' with violence. Zi. Tlie crystals have a penetrating, old-clieesy odor. A minute portion placed upon the t<.ini;iic produces " drynes.s of the thmat, nausea, \omltim;', and diari'ho'a." In children the ellects agree with the symptoms of cholera infantum. Ten dixips of a coiKa'ntrated a(|ueous solution of t)rotoxicon fi'om milk thi'ee months old, })laccd iu the mouth of a small dog three weeks old, in a few tiiinutes caused "frothing at the mouth, jetching. vomiting of frothy liquid, I'ajiid breathing, niu.^cular spai-m n\t'i- the abdomen, and after some time wateiy stools." similar ef- fects were obtained with cats, and subseiiuent dissection showeti the mucous mendjrane of the stoiiuu'li and intestines to be blanched and soft. Of diazobenzene butyrate, artificially pre- j)are(i,^ 0.010 ton I In' lower animals," with report of di'termination of diazo- benzi'nr, ibid , l, 2H1. ' Ky mi'tiind of ortion in vail') ian oil, according to s(jme obser\ers. Obtained h\ oxidation of the lessei' pieutyl alcohol (!•!,<) of fusel oil. (4) Methybpropyl acetic acid, CIL/Jgllg. CO.,!!. Made from methyl-propybcarbinol. Oedinaey Yalekic Acid. Isovaleeic Acid Inactive Valeric Acid. Tlie second of tlie pentoic acids above named. Baldriansiiure. — A constituent of " valerian i-oot,'' the rhizome and rootlets of Yaleriaiia officinalis, and a part of the volatile oil of valerian. Peported as found in digitalis, Artimisia Absin- ' Per cent, of polassiuni calciiUUcil, 2J.42; found, 23.92. ORDIN. IRY I 'A LEIUC A CID. 5 1 9 thiniii, Antheiiiis iiohilis, Saiiilmcu.s iiii;i-;i, \'ilmrinuii opuliis, and other plants. JMaiiiil'acturcd by oxiiialion (distillation fnini dichi'oniate and sulplmric acid) of isoaniyl alcoliol (isohiityl car- binol), tlie principal alcoliol of fused oil. \ aleric aci() parts of S()r; alco- hol; bismuth valerate (1»asic), insoluble in water; leai.l valerate, (normal) soluble in M'atei', (basic) sparingly soluble; mercuric valerate, soluble; mercurous valerate, slightly soluble; cupric valerate, moderately soluble; silver valerate, slightly solulile, in water. — To test-i)apers free valeric acid has the acid reaction; the alkali valerates, neutral reaction. (I, — Is(n'aleric acid is chai'acterized liy its odor as a free acid, and by the odor of its amyl ester. This is formed by distilling -with a little ordinary amyl alcohol and twice its (piantitj of 520 VALERIC ACIDS. sulphuric acid. Precipitates are obtained, with alkah valerates. on adding aluminium sulphate or silver nitrate, not by addition of lead normal acetate. Cupric acetate, with concentrated free valeric acid, yields oily droplets of anhydrous valerate of cop- per, which, on standing, ci-ystallize as hydrate (distinction frorti butyrate, which in solution not very dilute i:ives an immediate precipitate of butyrate of copper). e. — Separation. — Isovaleric acid is separated from non-vola- tile matters, and obtained from. its salts, by distillation, adding diluted sulphmic acid if necessary to liberate it. From other volatile acids fractional saturation and distillation may be em- ployed, having regard to boiling points. — Separation from aqueous solutions is effected by ether more readily than by distillation. The aqueous solution, in which the valeric acid is liberated, if need be, by adding potassium bisulphate, is saturated with sodium sulphate and shaken out with portions of ether. f. — Quantituti've. — The valeric acids may be estimated volu- metricall}' with standard solutions of alkali, using eithe*' litmus- papers or phenol-phthalein as the indicator of saturation. Each c.c. of normal solution of alkali indicates O.lOii gram of real valeric acid ; each c.c. decinormal solution, 0.0102 gram. And if 5.1 grams of material be taken, c.c. of .N alkali X 2 ^ per cent, of acid ; if 1.02 grams be taken, c.c. of -^^ = per cent. g. — Tests of Purity. — '' Purified by distillation, valeric acid is a colorless liquid, oleaginous, of a peculiar disagreeable odor. It dissolves in 30 jjarts of water at 20° C, and in all proportions of alcohol or ether. Its specific gravity at 0° C. is about 0.955. It boils at 175° C."(Ph. Fran.) — "A specific gravity above 0.950, and solubility in less than 25 parts of water, indicates pre- sence of water, acetic or butyric acid, amyl alcohol or aldehyde. The last two are known by their insolubility in ammonia-water. If half of a mixture of equal parts of butyric and valeric acids be neutralized with alkali, and the whole distilled together, the butyric acid goes over, and will be found soluble in not above 10 parts of water " (Fltickiger's " Phar. Chera.") VAPOR TENSION, Deteeminatiom oe. See p 237. VINEGAR. See Acetic Acid, p. 14-. INDEX. Abies Canadensis, tannin of 481 Absinthin 7 Absinthin, in plant analysis 435 Acetate of lime 11 xVcetate of sodium 11 Acetic acid 7 Acid Azo-rubin 184 Acid Jlageuta 184 Acid Naphthol Yellow 185 Acids, organic, in plant analy- sis 415,419, 424 Acid tartrate of potassium 496 Aconelline 387 Aconine 18 Aconite assay ' 27 Aconite roots 19 J con itic acid 30 Aconitic acid from citric 80 Aconite alkaloids 17 Aconitine 17 Aconitine poisoning, analysis for. 28 Aconitine, saponification of. .. . 171 Aconitines of commerce 30 Aconitum, aconitic acid in 30 Aconitum, species of 19 ^sculin 31 Air-pump for combustions 222 Albumens, in plant analysis . . 416, 420, 425 Alcoholic beverages, analysis of, for strychnine 460 Alcohols in fusel oil ZV) Alder tannin , . . 481 Ale, analysis of, for strychnine. . 460 Alizarin 189, 197 Alkali blue 187 Alktihdd«, color-tests of 50 Alkaloids, in general :)3 Alkaloids, in plant analysis. .418, 424 Alkaloids, reagents for 42 Alkaloids, separation of 83 Alkanet 194 Alkanna- violet 194 AUoxantin 80 Alnus glutinosa, tannin of 481 Aloes dye 188 Aloes, tests for. 56 Aloes, varieties 54 Atoins 54 Amalic acid 80 Amethyst 188 Amido-azo-benzol 185 Amido-succinaniic acid 58 Amido-succinic acid 58 Amphicreatinine 428 Amygdalic acid 57 ,1 mygdalin 56 Amygdalin in color-tests with sul- phuric acid 50 Amyl alcohols 315 Analysis, inorganic and organic. 393 Analytical chemistry of carbon compounds 391 Andromeda Leschenaultii, oil of. 433 Aniline blue 187, 197 Aniline brown 197 Aniline dyes with immiscible sol- vents 195 Aniline dyes in inks 482 Aniline green 194 Andine orange 197 Aniline reds 189, 191, 197 Aniline violet 197 Aniline yellow 197 Anisol-red 184 Annatto 193 Anthemis nobilis 519 Anthracene oil, a fraction from coal-tar 895 Aniipi/rine 168 52" 522 INDEX. Apo-alkaloids of the Aconites. . . 19 Apo-dioinchonine 91 Apo-diquinidine, 91 Apomorphine 390 Apomorphine in color-tests with sulphuric acid 50 Apomorphine in color-tests with Froehde's reagent 51 Arhutin 57 Archil 193 Argols 496 Ariciue 93 Arsenic, qualitative analysis for. . 300 Artemisia absinthium 7, 518 Ash, estimation of 410 Asphalt, a fraction from coal-tar. SO.") As2}arogin 58 Aspartio acid 58 Atropine :j44 Atropine, saponification of 171 Atropine, tests of purity of 357 Auramin 185 Auric chloride with alkaloids. ... 49 Azo color compounds 186 Azo compounds from Lieber- mann's test 510 Azotometer, SchifE's 321 Baking-powders 500 Baldriansiiure 518 Balsams containing cinnamic acid 69, 71 Barbaloin 54 Bebirine 58 Beer, amdysis of, for salicylic acid 440 Beer, analysis of, for strychnine. 460 Beeswax, melting and congealing points 371 Belladonna, alkaloids of 340 Belladonna assay 351 Belladonna extract, assay of 353 Belladonna plasters, assay of . . . . 3."i3 Belladonna root or leaves, assay of 351 Bengal-red 183 Benzene, certain derivatives of. . 434 Benzoates 63 BenzoSsiiure 59 Benzoir acid 59 Benzoic acid, tests of purity of. . . 66 Benzoin 59 Benzoyl-ecgonine 170, 173 Benzyl fluorescein 183 Berberine 71 Betaine 438 Biberine 58 Bichromate, for combustions. . . . 310 Biebrich scarlet 184 Bisn}arek brown ]S(i Bitaiiratc of potassium 490 Bitter-almond oil, relation to ben- zoic acid 60, 63 Blue coloring matters 187 Blue inks 483 Bohea 5! 4 Bone fat, sp. gr. and melting of . . 374 Bordeaux blue 184 Borosalicylic acid 438 Boheatannic acid 481 Boheic acid 481 Brazil-wood color 193 Brazil-wood in inks 483 Bromine, estimation of 330 Bromine, qualitative analysis for. 300 Bromine reactions with alkaloids 47 Brucine 463 Brueine in color-tests with sul- phuric acid 50 Brucine in color-tests with l"'roehde's reagent 51 Brucine in color-tests with ni- tric acid 53 Brucine separation from strych- nine 458 Butter 393 Butter-analysis, competence of. . . 310 Butter-analysis, interpretation of 300 Butter, artificial colors of 295 Butter, estimation of rancidity of 395 Butter-fat 298 Butter-fat, metliods of analysis of 300 Butter, microscopic analysis of. . . 397 Butter, odor- test of 298 INDEX. 523 Bultfi-, salicylic acid in 441 Butter-suinis, viscosity of 21)7 Butter substitutes 300 B^itijrk iicid 75 Buxine "18 ("aeau butler, melting of 2()9, 273 Cadaveric alkaloids 42t) Cadaverinc 427 CnJJ, ine 77 CaSi'ine from theobromine 514 Caffetannic acid 4sO Caffelannin 480 Calcium tartrate 498 Camphors, iu plant analysis 418 Canned fruits, analysis of, for salicylic acid 440 Cantharides, assay of 84 Caiitliarkhii 83 Caprio acid 21.") Ca[iiuic acid 245 Caprylie acid 245 Capsicum, m plant analysis 425 Carbolates 398, 401 Gai!ii>lic acid 39(i Carbolic acid, as._ay of 404 Carijolic oil, as a fraction from coal-tar 395 Carbolsiiure 390 Carbon and Hydrogen esliina- lion 208, 219 Carbon, qualitative analysis for. . 19.S Carius's method for halogens or sulphur 230 Caryophyllin, in plant analysis.. 425 (J.iscarilline, i-n plant analy.sis. . . . 425 (M:4nr oil 289 Ca^ior oil, melting of fat acids of 2U9 ('astoroil, tests of purity of 290 (.'atecliin 479 Catechutannic acid 479 Catechidannin 479 Clelandine, cotistiluent of 84 Cell formation not a direct result of chemism 391 Cellulose, in plant analysis, 417, 431, 430 Cev.adino, saponification of 171 ( 'liairamidine 93 Cliairainiiie 93 Chi'ese pofson 514 Clieese poison, as a ptomaine. . . . 429 ( 'lididoniiii' 84 t'jjestnut-red i^'i ( 'hcslniit tannin 483 Chinidine 154 Chiniii 135 Clnnoidine 94 (Jli inoline 105 Chinoplitalon 185 Chitenine 138 CIdoride of calcium, for analysis. 305 Chloride of calcium lubes 300 V/doriitr, es/iinalio7b of 330 Chlorine, qualitative analysis, for 300 Chlompliyll, in plant analy^is, 418, 424 t.'hiiciilate nut 513 Choline 427 Chromate in inlis 483 Chromate of lead, for conibus- tion.s 203, 210 Chrysammic acid 50, 18^^, 97 Chrysoidin 180 Cider, analysi.^ of, for salicylic acid 440 Cinchaniidine 93 ( 'iiirlionit Allcaloids 90 Cinchona alkaloids, constitution of 97 (.'inclicina alkaloids, yield of 90 Cinchona as.say 102 Cinchona barks, alkaloidal strengths of 90 Cinchona l)arks, assay of 103 Cinchonamine 92 Ciiiclionicine 91 < '•lu'/ioaif/ihc 157 Cinchonidine salts 158 Cinchonidine, tests of purity of. 159 / 'iiK'/KHiiiit' 1(1) < Mnclionine salts 102 524 INDEX. Cinchonine, tests for purity of. . . 164 Cinchotannic acid 479 Cinchotannin 479 Ciuchotine 93 C'innamates 69, 70 CinRamein 71 Cinnamene 71 Cinnamic acid 69 Cinnamic aldehyde 69 Cinnamon oil, relation of 69 Citracohic anhydride 31 Citrates 86 Cl/nc acid 85 Citric acid, tests of purity o£. . . . 89 Citronenssiure 85 Citronin 186 Coal-tar dislillation, fractions from 395 Coca A Ikaloids 170 Cocaicine 173 Cocaine 170, 174 Cocaine hydrochloride. .174, 175, 180 Cocaine salts 174, 175 Cocaine, tests for purity of 180 Cocainoidine 170, 172 Coca leaves, assay of 178 Cocliineal 193 Cochineal violet 194 Cocoa nibs 513 Cocoanut oil, melting of 269, 274 Cocoa i^hells 513 Codamine 359 Codeine 388 CofEee, assay of 81 Coffee, tannin of 480 Collcin 77 Cola nut, assay of 81 Cola nut, theobromine in 513 Colchicine in color-test vrith sul- phuric acid 50 Colchicine in color-test with Proehde's reagent 51 Colchicine, in plant analysis 425 Colocynthin in color-tests with Froehde's reagent 51 Colocynthin, in plant analysis. . . 425 Colombin in color-tests with sul- phuric acid 50' Coloring Materials 181 Coloring matters of butter 295 Color-reactions of the alkaloids. . 50 Colors, in plant analysis 419 Combustion-furnaces 208, 216 Combustions, analytical 201 Combustion tubing 206 Conchairamidine 93 Conchairamine 92 Conchinine 154 Coucusconidine 93 Concuseonine 93 Congo-red 184 Conine in color-test with sulphu- ric acid 50 Conquinamine 93 Convallaraerin, in plant analysis. . 425 Copper, for combustions 204 Copper oxide, for organic combus- tions 203 Coptis, per cent, of berberine in . . 73 Copying inks 483 Corallin 196, 197 Corallin red 191 Corulein 186, 196 Cotarnine 360, 888 Cottonseed oil 287 Co/tun-seed stearin 289 Cranberries, constituent of 85 Cream of Tartar 496 Creosote, compared with carbolic acid 394, 401 Creosote oil, of coal-tar distilla- tions 395 Cresols 394 Cresol-sulphonic acids 406 Cresotic acids 434, 443 Cresylic acid 394 Crocein scarlet 184 Cruscocreatinine 428 Cryptopine 360, 362 Gryptopine in color- test with sul- phuric acid 50 Crysolin 185 INDEX. 525 Cubebin in color-tests with sulphu- ric acid 50 Cubebin, in plant analysis 425 Cuprea barlis, constituents of 93 Ciipreine 92 Cupreiue, test for 153 Cunirine in color-test with sulphu- ric acid 50, C2 Cui'arine interference with strych- nine test 454 Curcumin dye 185 Cuscouine 93 Dalican's method for fats , 353 Daphniii, in plant analysis 435 Daturine 340, 341, ;i44 Dead oils of coal-tar distillations. . 395 Deduction of chemical formulcB. .. 337 Delphinine, in plant analysis 435 Dextnnes, in plant analysis . . 420, 435 DexU'otartaric acid 485 Diazobenzeiie compounds 515 Diazo color compounds 184 Dichonehonine 91 Dicinohonicine 91, 95 Dioonchiiiine 91 Digallic acid 474 Digitalein, in plant analysis 425 Dihydroxyl-qiiiniiie 138 Dimethyl-amido-azo benzol 185 Dimethyloxyquinizine lOi! Dmiethylprotooateohuic acid 18 Dimethyl xanthine 213 Diphenyl amine yellow 180 Diquinicine 91, 95 Dragendorff's plan for plant analysis 423 Dragendorff's process for alka- loids 33 Drying oils 281 Duboisia, alkaloids of 840 Duboisine 340 Ecgonine..... 170, 173 Eisessig 8 Elaidic acid 247 Elaidin test 281 Elateiln in color-tests with Froehde's reagent 51 Elaterin in color tests with sul- phuric acid 50 Elaterin, in plant analysis 435 ElemeiUary analysis 198 Elementary analysis, inorganic and organic o93 Elementary organic analysis, quantitative 201 Eosins 183 Eusin scarlet 183 Ericdlin, in plant analysis 425 Brlenmeyer's furnace 308 Erythroxylon Coca 170 Essigsiiure 7 Essigsiluren Kalk 11 Ethyl-orange 186 Extraction apparatus 409 Extraction-apparatuses for liquids (illustrated) 38 Extract of belladonna, assay of. . . 353 Extract of nux-vomica, assay of.. 457 Fat acids, percentages of, insol- uble 256 Fat acids, quantitative determina- tions of 350 Far oils, specific gravity of 262 Fats and Oils 238 Fatty acid series 239, 245, 346 Filter of Gooch 409 Flavanilin 185 Plei.scher's estimation of tartaric acid 495 Formic acid 313 Formulas, deduction of 337 Froehde's reagent for alkaloids. .. 51 Fruits, percentage ciT citric acid in 85 Fusel oil 314 Fustic color 193 Pu.stio tannin 47!) Gadinine 43? 526 INDEX. Gallein 183 QalUc acid 330 Gallic anhydride 474 Gallo-L-yanin 188 Lrallotaniiin 474 Ga.^uous bodies, organic combus- tions ol 216 GauUhnria, oil of 43o Geisler's report on teas 505 Gelseminine in color-test with sul- phuric acid 50 Gelseminine iu color-test with ni- tric acid 52, 454 Gelsemine, in plant analysis 425 Gerbsauren 4G5 Gerland's method for estimating tannins 471 Garrard's test for atropine 348 Glacial acetic acid 8, 14 Glaser's combustion furnace 310 Gluco:3e, in plant analysis. . .415, 419, 435 Glucosides, in plant analysis.. 413, 4iy, 424 Glucoside-tannins 406 Glycerides, as a chemical class. . . 333 Crlyceriii 333 Glycerin, tests of purity of 338 Gnoscopine 360 Gnoscopine in color-test with sul- phuric acid 50 Gold chloride with alkaloids 49 Gooch's filter 409 Gratiolin, in plant analysis 435 Green. Coloring 3Iatters 180, 103 Green oil or anthracine oil 3ii5 Guarana, assay of 81 Guaranine 77 Gums, in plant analysis 416, 430 Hager's method for estimating tannins 473 Halogens, estimation of 336 Hammer's method for estimating tannins 473 Hard pitch 895 Hectograpbio ink 483 Hehuer's method for fats 230 Ilehner's number, interpretation of 301 Helleborin, in plant analysis 435 Heiiicpio acid 363 Hemlock bark, tannin of 481 Hempseed oil, drying test of 283 IlelvcUa green 187 Heraf )athite 131 Hesse's lest for quinine sulphate.. 151 Hippuric acid in urine 63 Hippuric acid, source of benzoic. 60 llotmann's violet 188 Ilnlzessigsauren Kalk 11 IIoDiatrupine 343 lioinocinchonidine 93 Iloiuoqiiinine 93 Jloi) bitter, in plant analysis. .. 435 Hop-tannin 481 Hiibl's method with fats ... . 358 Humus, in plant analysis 417, 430 l-Iydrasiine 339 " Hydrastine," yellow alkaloid. . . 73 Hydrastis, assay of 74 Hydrastis, constituent of 73 Hydrocinchonidine 91 Hydrocinchonine 93 Hydroconquinine 93 Ilydrocotarnine 360, 363 Hydrocyanic acid, from amygda- lin 57 Hydrogen, estimation of 308 Hydrogen, qualitative analysis foi 198 Hydroquinidine 91 Hydroquinine 91 Hydroxy-benzoic acids 433, 443 Hy droxy-xylenic acids 443 Eygrine 170, 173 Ilgoscine 343 Hyoscyamine 343 Hyoscyamus, alkaloids of 340 Hyoscyamus assay 853 Hyoscyamus leaves and seeds, assay of 353 INDEX. 527 Ilypogaic iicid 246, •ii\) li^asuriiie 440 :j:3 Immiscible solvents liuK'live valeric acid 518 Indelible inks 4H:f 483 193 Indii;o-blue 188 188 483 484 liik!< . Ink-stains, discharge of Inorganic analysis, relations to organic 393 Inorganic substances, in organic anal vsis 300 Inulin, in plant analysis 425 Iodine and methy! green 187 Jodiiu\ esiimalion of 230 Iodine numbers of fats 258 Iodine, qualitative analysis for. . 200 Iodine reacliojis with alkaloids. . 42 187 Iron-bUiing tannins 400 400 Isobutyl-carboxyl 518 Isobutvric acid (foot-note) 75 Isovnl crates (isovalerianates). . . . 519 I«)i-alrric (isovalerianic) acid. . . 518 Itaconic acid 31 Japaconine 18 Japaconitine 18 JauneN 186 Jervine in color-test with sulphu- ric acid 50 Johnson and Jenkins's method . . . 320 Katrines 167 Kerner's test for quinine, 139, 144, 140 KJeldahl's method for nitrogen . . . 334 KofEein '^7 Kottstorfer's method for fats 254 Kottstorfer's number, interpreta- tionof 304 Laulliopine 360, 362 Lard 390 Lard oil 393 Lard, tests of purity of 291 Laudanino 300, 302 Laudaiiosino 300, 303 Laudanum assay 385 Laurie acid 245 Laut's violet 188 Lead chromate, for organic analy- sis 303 Lees 111' tartar 490 Lemon-juice, assay of 89 Leucoline 105 Leuconidiiiea 428 Leukindophenol 18'":^ Lichen-red 192 Liebig's test for quinine 151 Light oil, of coal-tar distillations.. 395 Lignose, in plant analysis. . .418, 420. 420 Lime-juice 85, 89 Linuhic acid 249 Lii.o.xyn 249 Lin-seed oil 284 Linseed oil, tests of purity of 284 Liquids, organic combustions of.. 313 Liver, excretion of aconite alka- loids in 29 Liver, excretion of morphine in. . 373 Liver, excretion of strychnine in. . 450 Lobeline, in plant analysis 435 Loganin 447 Logwood blue 192 Logwood in inks 483 Lowenthal's method of estimating tannins 468 Luteolin 186 Mace oil, melting of 269, 373, 274 Jladder colors 189 Madder-red Iil3 Madder-violet 194 Mag(la,la-rcd 182 Magenta 1^3 IMalnchite green 1^i7 Ilalir acid 333 528 INDEX. Manchester brown Margario acid Martin's yellow Mate, assay of Mau vein ....'. Mayer's solution Mean molecular weight of fat acids J-leconic acid Meconic acid, as analytical proof of opium Meconiditie Meconidine in color-test with sul- phuric acid Meconin Me!->rs m^etliod for fats Melting and congealing points of fats Menyanthin, in plant analysis. . . Metacresol .MetaLungstic acid with alkaloids Metaxylenols 31l'L1i ylene blue Melhyl-orange ILjlhjl-theobromine Microscopical characteristics of alkaloids Microscopical distinctions of cin- chona alkaloids Microsublimation of alkaloids. . . . Middle oil, in coal-tar distillation Midriatic alkaloids Milk, examination of, for salicylic acid Mineral oils, separaf ion from gly- cerides ,. Molecules as final products of chemism Morintannic acid Morintannin MorjiJiine Morphine in color-test with sul- phuric acid Morphine in color-test with Proehde's reagent Morphine, salts of 364, 186 244 185 81 188 43 261 337 370 360 50 362 253 265 ■125 394 48 394 187 ISO 101 53 395 3;;9 440 391 479 479 362 50 51 365 Morpliine, tests of purity of 386 Morus tinctoria 479 Murexid 80 Murexoin 80 Murexoin test for theobromine... 513 Jliiscarine 427 Mygdaleiu 437 Myristic acid 245 Mytilotoxine 428 Nareeine 359, 362 Xarceine in color-test with sul- pliuric acid 50 Nareeine in color-test with nitric acid 52 Xarcotine 387 Narcotine in color-test with sul- phuric acid 50 Narcotine in color-test with nitric acid 52 Neuridine 427 Neurine 4i7, 428 Nitrogen and carbon, relative de- termination 233 Xitrogen estitnaiion 220, 221), 230, 233, 234 Xitrogen, total, in plant analysis . 411 Nitriisalieylic acids 438 Xutguils in inks 482 Niitgalls, treated for preparation of tannic acid 477 Xutgall-tannni 474 Nutmeg oil, melting ol 269, 372 Nux-vomica, alkaloids 447 Niix- vomica, assay of 456 Oak-bark tannin 478 Oils and fats 23^ Oil of birch 433 Oils, fixed 238 Oils, fixed, in plant analysis. ..418 424 Oils, volatile, in plant analysis. . .412, 423 Olive oil, tests of purity of 385 Opianio acid 362, 388 Opium alkaloids 358 Opium assay 374 IXDEX. 529 Orcein 193 Organic analysis, divisions of . . . . 391 Organic matter 391 Orseille 193 Oxalate oi calcium, in plant analy- sis 436 Oxygen, direct estimation of . ... 334 Oxymorphine 3.")'J Naphthalene-Carmine 1S3 Naphthalene, source of benzoic acid 60 Naphthalene- Yellow 185 Nataloiii 54 Nitric acid reactions with alka- loids 51 Nitrogen, qualitative analysis lor.. 199 Oleic acid 246 Olein 24(i Oleomargarin 2!»3 Olire-lcenie! oil 287 Oliveoil 285 Opium alkaloids 35b Opium, assay of 374 Orange II 186 Orange G 180 Oranges, constituent of 85 Otto's process for alkaloids 33 Oxaiic acid, separation from fruit juici-'S 336 Oxygen gas, for organic combus- tions 203 Oxylinoleic acid 249 Palmitic acid 244 Palm oil, melting and congealing of 369, 274 Papaverine 359, 363 Papaverine in color-test with sul- phuric acid 50 Papaver soraniferum 358 Paraoresol 'j94 Paraffin, melting and congealing.. 373 Paraffins, separation from glyce- rides 274 Paratartaric acid 133 Paraxylenol 394 Paricine 93 Ptirso ns' 6 plan for plant analysis.. 408 Pathological tannins 467 Paulinia, constituent ot 77 Paytainine 93 Paytine 93 Peanut oil, melting of 269, 374 Pectous substances, in plant analy- sis 410, 420, 431, 425 Pe'coe .:04 Pelosin 58 Pentoic acids 518 Ferkiu's method for fats 355 PerUin's violet 188 Persian berries 193 Phenol 393 Phenols 394 Pheiiolsulpliurio acid and its salts 405 Phenyl-acrylic acid 69 Phenylene brown 186 Phenylsulphuric acid (foot-note). . 406 Phenylsulphuric acid in the urine 402 Phlobaphene, in plant analysis. . . 424 Phloridzin in color-tests with sul- phuric acid 50 Phloxin 183 Phosphine 185 Phosphomolybdates 46 Phosphorus, qualitative analysis for 199 Physalin, in plant analysis 425 Physetoleic acid 346, 350 Physiological tannins 467 Physostigmine in color-test with sulphuric acid 50 Physostigmine in color-test with nil riu acid 53 Physostigmine, in plant analysis. . 435 Phytochemioal analysis 107 Pieraconitine 18 Picric arid 398 Picric acid icifli. alkaloids 48 Picric acid, in scheme of color an- alysis 1 85 Piorotoxin, in plant analysis 135 S30 INDEX. Pilocarpine, in plant analysis. ... 4-5 Pineapple essence 75, 76 Pipeline, in plant analysis . . .... 425 Piperine, saponification of 171 Pitch, a residue of coal-tar distil- lation 395 Piltiri.ne 341 Plant analysis 407 Plasters of belladonna, analysis of 353 J'lulinic chloride with alkaloids. . 49 Poisoning by alkaloids, analyses for 33 Poisoning by atropine, analysis for 354 Poisoning by carbolic acid, analy- sis for 402 Poisoning by morphine, analysis for ". .. 370 Poisoning by strychnine, analysis for 458, 449 Poisons, ptomaines in analysis for, 427, 429 Ponceau R 184 Poppy oil, drying of 282 Populin in color-tests with sulphu- ric acid 50 Populin, in plant analysis 425 Potash-bulbs 207 Potash solution, for elementniy analysis 205 Potassium bismuth iodide 47 Potassium cadmium iodide 47 Potassium diazobenzene 517 Pota.isium mercuric iodide 43 Printer's ink 483 Protocatechuic acid formed from tannins 466 Protopine 360, 362 Proximate analysis, inorganic and organic 392 Prussian blue 192 Pseudaconine 18 Pseudaconitine 18 Pseudomorphine 359, 362 Pseudoxanthine 428 Ptomaines 426 Puree 186 Purpurin 190 Purpurogallin 481 Putrescine 437 Pyridine type of alkaloids. .340, 97, 171 Pyrogallic acid 430 Pyrogallol 430 Pyrogallol formed from tannins. . 406 Pyrogallol-phthalein 183 Pyrolignate of lime 11 Quassin, in plant analysis 425 Quercitannio acid 478 Quercitrin 193 Quinamicine 92 Quinamidine 92 Quinamine 93 Quinicine 9 L Quinidamine 93 Qninidine 1 54 Quiiiidine salts 155 Quinidine, tests of purity of 156 Quinine 135, 148 Quinine, assay of 139 Quinine bisulphate 127, 139, 149 Quinine hydrates 136, 128, 148 Quinine hydrobromide... 127, 139, 147 Quinine hydrochloride... 127, 139, 117 Quinine oxalate 137, 139 Quinine Pills, assay of 134 Quinine sulphate 136, 139, 139 Quinine tannate 139 Quinine tartrate 137, 139 Quinine, tests of purity of 134 Quinine valerianate 137, 139, 147 Quinoidine , 94 QiUnoline 165 Quinoline-red 183 Quinoline salts 166 Quinoline type in structure of al- kaloids 97 Quinoline yellow 185 Racemic acid 432 Rancidity of butters 395 Rape oil, melting of fat acids of. . 269 Reagents for alkaloids 43 Red coloring matters. . . .183, 188, 193 Red inks 483 INDEX. 531 Reil oil or anthracene oil liegiiia purple KoR'hort's lustliod I'or fats Reioliort's number, iiiterpretalinu of Keniijiii barks, constituents of. . . Hes/'ii oils Resins, in plant analysis . . . .418, Jictiim, separation fromghjceridis Rhodidine Rhoeadine Rhoeagenine. Ricinoleic acid Roccellin Rochleder's method of plant an- alysis Rosaniline blue Rosaniline salts Rosin oils Rosin, separation from sorips. . . . Rotatory pi)ici;r of cinchona alka- loids Ruffle's method for nitrogen .... Sabadilline in color-test with sul- phuric acid Saliadilline in color-test with nitric acid Sabadilline, in plant analysis. . . . Sali^ilrine, in plant analysis Sufflower Salliower-red .Sallranin class of colors Satf ranisol Saffron-carmine Salicin in color-tests with sulphu- ric acid Salicin in color-tests with Froehde's reagent Salicin, in plant analysis Salirylates Salic ijlic acid Salicylic acid, tests of purity of. . Salicyl-sulphonic acid Salicyluric acid Sandal 189, 395 188 25:i 303 !»-' 380 424 '274 ]8;! 300 ;!iJO 248 184 407 I.ST is;! 2S0 3r4 121 233 50 425 425 189 191 is:_i is:! 193 50 51 425 4:;7 433 412 439 445 191 Santonin, in plant analysis Saiionilicatioii coefficients Saponin, in plant analysis Siiprinc Sarsaparillin in coliii--l,('sls with sulphuric acid Schilf 's azotoineter Senegin in color-test with suljilm- ric acid Senegin, in plant analysis Separators, tor alln, by Lt. Wm. S. Benson. 8vo, cloth $iU.OU LUNGE, GEO.' A Theoretical and Practical Treatise on the Manufacture of Sulphuric Acid and Alkali with the Collateral Branches. Vol. I. Sulphuric Acid. Second Edition, Revised and enlarged. 342 illustrations. 8vo, cloth $15.00 Vol. II. Second JEdition, revised and enlarged. 8vo, cloth. .$16.80 Vol. III. 8vo, cloth. New Edition, 1896 $15.00 LUNGE, GEO., and HURTER, F. The Alkali Maker's Pocket Book. Tables and Analytical Methods for Manufacturers of Sulphuric Acid, Nitric Acid, Soda, Potash and Ammonia. Second Edition. 12mo, cloth $3.00 LUaUER, LEA McILVAINE, Ph. D. Minerals in Bock Sections. The Practical Method of Identifying Minerals in Bock Sections with the microscope. Especially arranged for Students in Technical and Sientificc Schools. 8vo, cloth. Illus- trated net, $1.50 MACCORD, Prof. 0. W. A Practical Treatise on the SUde- Valve by Eccentrics, examining by methods the action of the Eccentric upon the Slide- Valve, and explaining the practical processes of laying out the movements, adapting the Valve for its various duties in the Steam-Engine. Second Edition. Illustrated. 4to, cloth $2.50 MAGUIRE, Capt. EDWARD, U. S. A. The Attack and Defence of Coast Fortifications. With Maps and Numerous Illustrations. 8vo, cloth $2.50 MAGUIRE, "WM. R. Domestic Sanitary Drainage and Plumbing Lectures on Practical Sanitation. 332 illustrations. 8vo ,. . $4.00 MARKS, EDWARD C. R. Mechanical Engineering Materials : Their Properties and Treatment in Construction. 12mo, cloth. Illustrated 60 Notes on the Construction of Cranes and Lifting Machinery. 12mo, cloth $1.00 MARKS, G. C. Hydraulic Machinery Employed in the concentration and Transmission of Power. 12mo, cloth. . . .|1,25 MAVER, WM. American Telegraphy : Systems, Ap- paratus, Operation. 450 iUiistrations. 8vo, cloth $3.50 MAYER, Prof. A. M. Lecture Notes on Physics. 8vo, cloth ^2,00 McCULLOCH, Prof. R. S. Elemenjtary Treatise on the Mechanical Theory of Heat, and its application to Air and Steam Engines. 8vo, cloth i $3.50 McNeill, Bedford. McNeill's Code. Arranged to meet the requirements of Mining, Metallurgical and Civil Engi- neers, Directors of Mining, Smelting and other Companies, Bankers, Stock and Share Brokers, Solicitors, Accountants, Financiers, and General Merchants. Safety and Secrecy. 8vo, cloth $6 00 JSCIENTIFIO PUBLICATIONS. 19 MERRILL, Col. WM. E., U.S.A. Iron Truss Bridges for Railroads. 'I'he method of calculating strains in Trusses, with a careful comparison of the most prominent Trusses, in reference to economy in combination, etc. Illustrated. 4to, cloth. Fourth FAition $5.00 METAL TURNING. By a Foreman Pattern Maker. Illustrated with 81 engravings. 12mo, cloth $1.50 MINIipiE, WM. Mechanical Drawing. A Textbook of Geometrical Drawing for the use of Mechanics and Schools, in which the Definitions and Rules of Geometry are familiarlj- explained ; the Practical Problems are arranged from the most simple to the more complex, and in their description technicalities are avoided as much as possible. With illustrations for Drawing Plans, Sections, and Eleva- tions of Railways and Machinery ; an Introduction to Isometrical Draw- ing, and an Essay on Linear Perspective and Shadows. Illustrated with over 200 diagrams engraved on steel. Ninth thousand. With an appendix on the Theory and Application of Colors. 8vo, cloth. .$4.00 Geometrical Draiving. Abridged from the Octavo edition, for the use of schools. Illustrated with 48 steel plates. Ninth edition. 12mo, cloth $2.00 MODERN METEOROLOGY. A Series of Six Lectures, delivered under the auspices of the Meteorological Society in 1870. Dlustrated. 12mo, cloth $1.50 MOREING, C. A., andNEAL, THOMAS. Telegraphic Mining Code Alphabetically arranged. Second Edition. 8vo, cloth $8.40 MORRIS, E. Easy Rules for the Measurement of Earth- works by means of the Prismoidal Formula. 8vo, cloth, illus $1.50 MOSES, ALFRED J., and PARSONS, C. L. Elements of Mineralogy, Crystallography and Blowpipe Analysis from a prac- tical standpoint. Second I'hoii.'^aiid. 8vo, cloth, 336 illus.. ;hY, $2.00 MOSES, ALFRED J. The Characters of Crystals. An Introduction to Physical Crystallograpby, containing 321 Illustra- tions and Diagrams. 8vo, 211 pp net, $2.00 MOELLER, F. C. G. Krupp's Steel Works. With 88 illustrations. By Felix Schmidt and A. INlontan, Authorized Translation from the German. 4to, cloth (I71 Prci.i.) MULLIN, JOSEPH P., M.E. Modem Moulding and Pattern -Making. A Practical Treatise upon Patteru-Shop and Foun- dry Work : embracing the Moulding of Pulleys, Spur Gears, ^^'orm Gears, Balance- Wheels, Stationary Engine and Locomotive Cylinders, Globe Valves, Tool Work, jNIining Machinery, Screw Propellers, Pat- tem-Shop Machinery, and the latest improvements in English and American Cupolas ; together with a large collection of original and carefully selected Rules and Tables for every-day use in the Drawing Ofi&ce, Pattern-Shop and Foundry. 12mo, cloth, illustrated $2.50 20 D. VAN NOSTBAND COMPANY'S MUNRO, JOHN, C.E., and JAMIBSON, ANDREW, C. E. A Pocketbook of Electrical Rules and Tables for the use of Electricians and Engineers. Thirteenth edition, revised and enlarged. With numerous diagrams. Pocket size. Leather. $2. 50 MURPHY, J. G., M.E. Practical Mining. A Field Manual for Mining Engineers. With Hints for Investors in Mining Properties. 16mo, morocco tncks $1.00 NAQTJET, A. Legal Chemistry. A Guide to the Detec- tion of Poisons, Falsification of Writings, Adulteration of Alimentary and Pharmaceutical Substances, Analysis of Ashes, and examination of Hair, Coins, Arms, and Stains, as applied to Chemical Jurisprudence, for the use of Chemists, Physicians, Lawyers, Pharmacists and Experts. Translated, with additions, including a list of books and memoirs on Toxicology, etc. , from the Prench, by J. P. Battershall, Ph. D. , with a preface by C. F. Chandler, Ph.D., M.D., LL.D. 12mo, cloth. .$2.00 NASMITH, JOSEPH, The Student's Cotton Spinning. Third edition, revised and cnlaryed. 8vo, cloth, 622 pages, 250 illustrations $3. 00 NEWAIiL., JOHN W. Plain Practical Directions for Drawing, Sizing and Cutting Bevel-Gears, showing how the Teeth may be cut in a Plain MUling Machine or Gear Cutter so as to give them a correct shiipe from end to end ; and showing how to get out all particulars for the Workshop without making any Drawings. Licluding a Full Set of Tables of Eeference. Folding Plates. 8vo, cloth $1.50 NEWCOMB, EDWARD W. Stepping Stones to Pho- tography. 12mo, cloth. Illustrated. N. Y., 1899 In press. NEWLANDS, JAMES. The Carpenters' and Joiners' Assistant : being a Comprehensive Treatise on the Selection, Prepara- tion and Strength of Materials, and the Mechanical Principles of Framing, with their application in Carpentry, Joinery, and Hand- Hailing ; also, a Complete Treatise on Sines ; and an illustrated Glos- sary of Terms used in Architecture and Building. Illustrated. Folio, half mor $15.00 NIPHER, FRANCIS E., A.M. Theory of Magnetic Measurements, with an appendix on the Method of Least Squares. 12mo, cloth $1.00 NOAD, HENRY M. The Students' Text Book of Electricity. A neiu edition, carefiUlp revised. With an Introduc- tion and additional chapters by W. H. Preece. With 471 illustrations. 12mo, cloth $4.00 NUGENT, E. Treatise on Optics; or, Light and Sight theoretically and practically treated, with the application to Fine Art and Industrial Pursuits. With 103 illustrations. 12mo, cloth. . .$1.50 O'CONNOR, HENRY. The Gas Engineer's Pocket Book. Comprising Tables, Notes and Memoranda; relating to the Manufacture, Distribution and Use of Coal Gas and the Construc- tion of Gas Works. 12mo, full leather, gilt edges . . .$3.50- SCIENTIFIC PUBLICATIONS. 21 OSBORN, FRANK C. Tables of Moments of Inertia, and Squares of Kadii of Gyration; Supplemented by others on the Ultimate and Safe Strength of Wrought Iron Columns, Safe Strength of Timber Beams, and Constants for readily obtaining the Shearing Stresses, Keaotions, and Bending Moments in Swing Bridges. 12mo, leather $3.00 OSTERBERG, MAX. Synopsis of Current Electrical Literature, compiled from Technical Journals and Magazines during 1896. 8vo, cloth $1.00' OUDIN, M. A. Standard Polyphase Apparatus and Systems. FuUy Illustrated $3.00 PAGE, DAVID. The Earth's Crust, A Handy Out- line of Geology. 16mo, cloth 75 PAIjAZ, a., ScD. a Treatise on Industrial Photome- try, with special application to Electric Lighting. Authorized trans- lation from the French by George W. Patterson, Jr. Second edition, revised. Svo, cloth. Illustrated $4.00 PARSHAIiL, H. F., and HOB ART, H. M. Armature Windings of Electric Machines. With 140 full page plates, 65 ta- bles, and 165 pages of descriptive letter-press. 4to, cloth $7 50 PARSHAXL, H. F. Electrical Equipment of Tram- ways {In Press.) PEIRCE, B. System of Analytic Mechanics. 4to, cloth $10.00 Linear Associative Algebra. New edition with addenda and notes by C. L. Pierce. 4to, cloth $4.00 PERRINE, F. A. C, A. M., D. Sc. Conductors for Elec- trical Distribution ; Their Manufacture and Materials, the Calcula- tion of Circuits, Pole Line Construction, Underground Working and other Uses In Press. PERRY, JOHN. Applied Mechanics. A Treatise tor tiie use of students who have time to work experimental, numerical and graphical exercises illustrating the subject. Svo, cloth, 650 pages "e«. $2.50 PHILLIPS, JOSHUA. Engineering Chemistry. A Practical Treatise for the use of Analytical Chemists, Engineers, Iron Masters, Iron Founders, students and others. Comprising methods of Analysis and Valuation of the principal materials used in Engin- eering works, with numerous Analyses, Examples and Suggestions. 314 ills. Second edition, revised and enlarged. Svo, cloth.. . .$4.00 PICKWORTH, CHAS. N. The Indicator Hand Book. A Practical Manual for Engineers. Part I. The Indicator : Its Construction and Application. 81 illustrations. 12mo, cloth. . .$1.50 22 D. VAN NOSTRAND COMPANY'S PICKWORTH, CHAS. N. The Slide Rule. A Prac- tical Manual of Instruction for all Users of the Modern Type of Slide Rule, containing Succint Explanation of the Principle of Slide Rule Computation, together with Numerous Rules and Practical Illustra- tions, exhibiting the Application of the Instrument to the Everyday Work of the Engineer, — Ciyil, Mechanical and Electrical. 12mo, flexible cloth. Fiflh edition 80 PLANE TABLE, The. Its Uses in Topographical Sur- veying. From the Papers of the United States Coast Survey. Illustrated. 8vo, cloth $2.00 "This work gives a description of the Plane Table employed at the United States Coast Survey office, and the manner of using it." PL ANTE, GASTON. The Storage of Electrical Energy, and Researches in the Effects created by Currents, combining Quan- tity with High Tension. Translated from the French by Paul B. Elwell. 89 illustrations. 8vo $4.00 PL ATTNEE,. Manual of Qualitative and Quantitative Analysis with the Blow-Pipe. From the last German edition, revised and enlarged, by Prof. Th. Richter, of the Royal Saxon Mining Academy. Translated by Prof. H. B. Cornwall, assisted by John H. Caswell. Illustrated with 87 woodcuts and one lithographic plate. Seventh edition, revised. 560 pages. 8vo, cloth $5.00 PLYMPTON, Prof GEO. W. The Blow-Pipe. A Guide to its use in the Determination of Salts and Minerals. Compiled from various sources. 12mo, cloth $1.50 The Aneroid Barometer : its Construction and TJse. Compiled from several sources. Fourth edition. 16mo, boards il- lustrated 50 Morocco, $1.00 POCKET LOGARITHMS, to Four Places of Decimals, including Logarithms of Numbers, and Logarithmic Sines and Tan- gents to Single Minutes. To which is added a Table of Natural Sines. Tangents, and Co-Tangents. 16mo, boards 50 POOLE, JOSEPH. The Practical Telephone Hand- Book and Guide to the Telephonic Exchange. 288 illustrations. Secona edition, rcvincd and enlarged. 12mo, cloth $1.50 POPE, F. L. Modern Practice of the Electric Tele- graph. A Technical Hand-Book for Electricians, Managers and Operators. Fifteenth edition, rewritten and enlarged, and fully illustrated. 8vo, cloth ; $1.50 POPPLEWELL, W. C. Elementary Treatise on Heat and Heat Engines. Specially adapted for engineers and students of engineering. 12mo, cloth, illustrated $3.00 POWLES, H. H. Steam Boilers {In H-ess.) SCIENTIFIC PUBLICATIONS. 23 PRAY, Jr., THOMAS. Twenty Years with the In- dicator; being a Practical Text-Book for tlie Engineer or the Student, with no oomjHex Formiilte. Illustrated. 8vo, cloth $2.50 Steam Tables and Engine Constant. Compiled from Reguault, Rnnkine and Dixon directly, making use of the exact records. 8vo, cloth $2 00 PRACTICAX IRON FOUNDING. By the author of "Pattern Making," &c., &c. Illustrated with over one hundred engravings. 12mo, cloth $1.50 PREECE, W. H. Electric Lamps {In Press.) PREECE, W. H., and STUBBS, A. T. Manual of Tele- phony. Illustrations and plates. 12mo, cloth $4.50 PREMIER tKDDE. (See Hawke, Wm. H.) PRESCOTT, Prof. A. B. Organic Analysis. A Manual of the Descriptive and Analytical Chemistry of certain Carbon Com- pounds in Common Use ; a Guide in the Qualitative and Quantitative Analysis of Organic Materials in Commercial and Pharmaceutical Assays, in the estimation of Impurities under Authorized Standards, and in Forensic Examinations for Poisons, with Directions for Ele- mentary Organic Analysis. Fourth cilition 8vo, cloth $5.00 Outlines of Proximate Organic Analysis, for the Identification, Sejjaration, and Quantitative Determination of the more commonly occurring Organic Compounds. Fourth fdition. 12mo, cloth $1.75 First Book in Qualitative Chemistry. Eighth ahtion. 12mo, cloth $1.50 and OTIS COE JOHNSON. Qualitative Chemical Analysis. A Guide in the Practical Study of Chemistry and in the work of Analysis. Fourth f ally rtrisi'd edition. With Descriptive Chemistry extended throughout $3.50 PRITCHARD, O. G. The Manufacture of Electric Light Carbons. Illustrated. 8vo, paper 60 PULIiEN, W. W. F. Application of Graphic Methods to the Design of Structures. Specially prepared for the use of En- gineers. A Treatment by Graphic Methods of tlie Forces and Princi- ples necessary for consideration in the De.sign of Engineering Struc- tures, Rdcil's, Bridges, Trusses, Framed Structures, Wells, Dams, Chimneys and Masonry Structures. 12Lno, cloth. Profusely Illus- trated ' "':', »^-50 PITLSIFER, W. H. Notes for a History of Lead. 8vo, cloth, gilt tops $400 PYNCHON, Prof. T. R. Introduction to Chemical Physics, designed for the use of Academies, Colleges, and High Schools. Illustrated with numerous engravmgs, and containing copious expeiiments with directions for preparing them. Xiw (dilinn, re- vised and cnlar(i<(l, and illustrated by 269 illustrations on wood. 8vo, cloth ■ $3.00 24 D. VAN NOSTRAND COMPANY'S RADFORD, Lieut. CYRUS S. Handbook on Naval Gunnery. Prepared by Authority of the Navy Department. For the use of U. S. Navy, U. S. Marine Corps and U. S. Naval Eeserves. Revised and enlarged, with the assistance of Stokely Morgan, Lieut. U. S. N. Third edition. 12mo, flexible leather $2.00 RAFTER, GEO. W. and M. N. BAKER. Sewage Dis- Disposal in the United States. Illustrations and folding plates. Second edition. 8vo, cloth $6.00 RAM, GILBERT S. The Incandescent Lamp and its Manufacture. 8vo. , cloth $3.00 RANDALL, J. E. A Practical Treatise on the Incan- descent Lamp. Illustrated. 16mo, cloth 50 RANDALL, P. M. Quartz Operator's Hand-book. New edition, revised and enlarged, fully illustrated. 12mo, cloth $2.00 RANKINE, W. J, MACQUORN. Applied Mechanics, Comprising the Principles of Statics and Cinematics, and Theory of Structures, Mechanism, and Machines. With numerous diagrams. Fifteenth edition. Thoroughly revised by W. J. Millar. 8vo, cloth $5.00 Civil Engineering. Comprising Engineering Sur- veys, Earthwork, Foundations, Masonry, Carpentry, Metal-Work, Roads, Railways, Canals, Rivers, Water- Works, Harbors, etc. With numerous tables and illustrations. Twentieth edition. Thoroughly revised by W. J. Millar. 8vo, cloth $6.50 Machinery and MillTvork. Comprising the Geom- etry, Motions, Work, Strength, Construction, and Objects of Machines, etc. Illustrated with nearly 300 woodcuts. Seventh edi- tion. Thoroughly revised by W. J. Millar. Svo, cloth $5.00 The Steam-Engine and Other Prime Movers. With diagram of the Mechanical Properties of Steam, folding plates, numerous tables and illustrations. Thirteenth edition. Thoroughly revised by W. J. Millar. Svo, cloth $5.00 Useful Rules and Tables for Engineers and Others. With appendix, tables, tests, and formulae for the use of Electrical Engineers. Comprising Submarine Electrical Engineering, Electric Lighting, and Transmission of Power. By Andrew Jamieson, O.E., F.R.S.E. Seventh edition. Thoroughly revised by W. J. Millar. Crown Svo, cloth $4.00 A Mechanical Text Book. By Prof. Macquom Rankine and E. F. B amber, C. E. With numerous illustrations. Fourth edition. Svo, cloth $3.50 RAPHAEL, F. C, Localisation of Faults in Electric Light Mains. Svo, cloth $2.00 RECKENZAUN, A, Electric Traction on Railways and Tramways. 213 Illustrations, 12mo, cloth $4.00 SCIEMTIFIC PUBLICATIONS. 25 REED'S ENGINEERS' HAND-BOOK, to the Local Marine Board Examinations for Certificates of Competency as First and Second Class Engineers. By W. H. Thorn. With the answers to the Elementary Questions. Illustrated by 297 diagrams and 36 large plates. Sixteenth edition, revised and enlarged. 8vo, cloth. .$5.00 REED'S Key to the Sixteenth Edition of Reed's En- gineer's Hand-book to the Board of Trade Examinations for First and Second Class Engineers and containing the working of all the ques- tions given in the examination papers. By W. H. Thorn. 8vo, cloth $3.00 Useful Hints to Sea-going Engineers, and How to Repair and Avoid "Break Downs;" also Appendices Containing Boiler Explosions, Useful Formulss, etc. With 36 diagrams and 1 plates. Second edition, revised and enlarged. 12mo, cloth. . .$1.40 Marine Boilers, A Treatise on the Causes and Pre- vention of their Priming, with Remarks on their General Manage- ment. Illustrated. 12mo, cloth $2.00 REINHARDT CHAS. W. Lettering for Draftsmen, Engineers and Students. A Practical System of Free-hand Lettering for Working Drawings. Fourth thousand. Oblong, boards. . .$1.00 RICE, J. M., and JOHNSON, W. W. On a New Method of obtaining the Differential of Functions, with especial reference to the Newtonian Conception of Rates or Velocities. 12mo, paper 50 RINGWALT, J. L. Development of Transportation Systems in the United States, Comprising a Comprehensive Descrip- tion of the leading features of advancement from the colonial era to the present time, in water channels, roads, turnpikes, canals, railways, vessels, vehicles, cars and locomotives ; the cost of transportation a various periods and places by the different methods ; the financial engineering, mechanical, governmental and popular questions that have arisen, and notable incidents in railway history, construction and operation. With illustrations of hundreds of typical objects. Quarto, half morocco $7.50 RIPPER, WILLIAM. A Course of Instruction in Machine Drawing and Design for Technical Schools and Engineer Students. With 52 plates and numerous explanatory engravings. Folio, cloth $6.00 ROEBLING, J. A. Long and Short Span Railway Bridges. Illustrated with large copperplate engravings of plans and views. Imperial folio, cloth $25.00 ROGERS, Prof. H. D. The Geology of Pennsylvania. A Government Survey, with a General View of the Geology of the United States, essays on the Coal Formation and its Fossils, and a description of the Coal Fields of North America and Great Britain. Illustrated with plates and engravings in the text. 3 vols, 4to, cloth, with portfolio of maps $15.00 26 D. VAN NOSTEAND COMPANY'S ROSE, JOSHUA, M.E. The Pattern-Makers' Assistant. Embracing Lathe Work, Branch Work, Core Work, Sweep Work, and Practical Gear Constructions, the Preparation and Use of Tools, together with a large collection of useful and valuable Tables. Eighteenth edition. Elustrated with 250 engravings. 8vo, cloth «2.50 Key to Engines and Engine-running. A Practical Treatise upon the Management of Steam Engines and Boilers for the "Use of Those who Desire to Pass an Examination to Take Charge of an Engine or Boiler. With numerous illustrations, and Instructions Upon Engineers' Calculations, Indicators, Diagrams, Engine Adjustments, and other Valuable Information necessary for Engineers and Fii-emen. 12mo, cl $2.50 SABINE, ROBERT. History and Progress of the Electric Telegraph. With descriptions of some of the apparatus. Second edition, luifh additions. 12mo, cloth $1.25 SAELTZER, ALEX. Treatise on Acoustics in connec- tion with Ventilation. 12mo, cloth $1.00 SALOMONS, Sir DAVID, M.A. Electric-Light Instal- lations. A Practical' Handbook. Eighth edition, revised and en- larged with numerous illustrations. Vol. I., The management of Accumulators. 12mo, cloth $1.50 Vol. II., Apparatus, 296 illustrations. 12mo., cloth $2.25 Vol. III., Applications, 12mo., cloth $1.50 SANFORD, P. GERALD. Nitro-Explosives. A Prac- tical Treatise concerning the Properties, Manufacture and Analysis of Nitrated Substances, including the Fulminates, Smokeless Pow- ders and Celluloid. 8vo. cloth, 270 pages $3.00 SATJNNIER, CLAUDIUS. Watchmaker's Handbook. A Workshop Companion for those eugaged in Watchmaking and allied Mechanical Arts. Translated by J. Tripplin and E. Rigg. Second edition, revised ivifh appendix. 12mo, cloth $3.50 SCHELLEN, Dr. H. Magneto-Electric and Dynamo- Electric Machines : their Construction amd Practical Applioation to Electric Lighting, and the Transmission of Power. Translated from the third German edition by N. S. Keith and Percy Neymann, Ph.D. With very large additions and notes relating to American Machines, by N. S. Keith. Vol. 1., with 353 illustrations. Second edition.. .^t.QQ SCHUMANN, F. A Manual of Heating and Ventilation in its Practical Application, for the use of Engineers and Architects. Embracing a series of Tables and Formulae for dimensions of heating, flow and return pipes for steam and hot- water boilers, flues, etc. 1 . mo, illustrated, full roan $1.50 Formulas and Tables for Architects and Engineers in calculating the strains and capacity of structures in Iron and Wood. 12mo, morocco, tucks $1.50 SCIENCE SERIES, The Van Nostrand. [See List, p. 33] SCIENTIFIC PUBLICATIONS. 27 SCRIBNER, J. M. Engineers' and Mechanics' Com- panion. Comprising United States Weights and Measures. Mensura- tion of Superfioes and Solids, Tables of Squares and Cubes, Square and Cube Roots, Circumference and Areas of Circles, the Mechanical Powers, Centres of Gravity, Gravitation of Bodies, Pendulums, Spe- cific Gravity of Bodies, Strength, Weight, and Crush of Materials, Water- Wheels, Hydrostatics, Hydraulics, Statics, Centres of Percus- sion and Gyi-ation, Friction Heat, Tables of the Weight of Metals, Scantling, etc. , Steam and the Steam-Engine. Twentieth, edition, rivitt'd. 16mo, full morocco $1.50 SEATON, A. E. A Manual of Marine Engineering. Comprisiug the Designing, Constmction and Working of Marine Machinery. With numerous tables and illustrations reduced from Working Drawings. Foiirta ntli edition. Revised throughout, with an additional chapter on Water Tube Boilers. 8vo, cloth. 1899. $6.00 and ROUNTHWAITE, H. M. A Pocketbook of Ma- rine Engineering Rules and Tables. For the use of :\I trine Engmeers and Naval Architects, Designers, Draughtsmen, Superintendents, and aU engaged in the design and construction of Marine Machinery, Naval and Mercantile. Fiftli, rdition, rruixcd and en/arged. Pocket size. Leather, with diagrams $3.00 SEXTON, A. HUMBOLDT. Fuel and Refractory Ma- terials. Hvo, cloth $2.00 SHIELDS, J. E. Notes on Engineering Construction. Embracing Discussions of the Pidnciples involved, and Descriptions of the Material employed in Tunnelling, Bridging, Canal and Road Building, etc. 12mo, cloth $l-oO SHOCK, WM. H. Steam Boilers, Their Design, Con- struction and Management. 4to, half morocco $15.00 SHREVE, S. H. A Treatise on the Strength of Bridges and Roofs Comprising the detei-mination of Algebraic formulas for strains in Horizontal, Inclined or Rafter, Triangular, Bowstring Lenticular, and other Trusses, from fixed and movmg loads, with practical applications, and examples, for the use of Students and Engineers. 87 woodcut iUus. Fourth edition. 8 vo, cloth. .. .$3.50 SHTJNK W E. The Field Engineer. A Handy Book of practice in the Survey, Location, and Truck-work of Railroads, con- taining a large collection of Rules and Tables, original and selected applicable to both the Standard and Narrow Gauge, and prepared ■irith special reference to the wants of the young Engineer. ^^'^''^w'A edition, rerisrd and enlarged. 12mo, morocco, tucks $2.60 SIMMS F W. A Treatise on the Principles and Prac- tice of' Levelling. Showing its application to purposes of Railway Engineering, and the Construction of Roads, etc Revised and oor- rSted, with the addition of Mr. Laws' Practical Examples for setting out Railway Curves. Illustrated. 8vo, cloth, $2.50 28 D. VAN NOSTRAND COMPANY'S SIMMS, W. F. Practical Tunnelling. Fourth edition, revised and greatly extended. With additional chapters illustrating recent practice by D. Kinnear Clark. With 36 plates and other illus- trations. Imperial 8vo, cloth ^^^- '^ SLATER, J. W. Sewage Treatment, Purification, and Utilization. A Practical Manual for the Use of Corporations, Local Boards, Medical Ofacers of Health, Inspectors of Nuisances, Chem- ists, Manufacturers, Eiparian Owners, Engineers, and Bate-payers. 12mo, cloth $2.25 SMITH, ISAAC W., C.E. The Theory of Deflections and of Latitudes and Depai-tures. With special applications to Curvilinear Surveys, for Alignments of Railway Tracks. Illustrated. 16mo, morocco, tucks $3.00 GUSTAVUS W. Notes on Life Insurance. The- oretical and Practical. Third edition, revised and enlarged. 8vo, cloth «2.00 SNELL, ALBION T, Electric Motive Power: The Transmission and Distribution of Electric Power by Continuous and Alternate Currents. With a Section on the Applications of Electricity to Mining Work. 8vo., cloth, illustrated $4.00 SPEYERS, CLARENCE L. Text Book of Physical Chemistry. 8vo, cloth $2.25 STAHL, A. W., and A. T. WOODS. Elementary Me- chanism. A Text-Book for Students of Mechanical Engineering. Fourth edition, enlarged. 12mo, cloth $2.00 STALEY, CADY, and PIERSON, GEO. S. The Separ- ate System of Sewerage : its Theory and Construction. Second edi- tion, revised. 8vo, cloth. With maps, plates and illustrations. .$8.00 STEVENSON, DAVID, F.R.S.N. The Principles and Practice of Canal and River Engineering. Revised by his sons David Alan Stevenson, B. Sc, F.R.S.E., and Charles Alexander Stevenson, B. Sc, F.R.S.E., Civil Engineer. Third edition, vAth 11 plates. 8vo, cloth $10.00 The Design and Construction of Harbors. A Treat- ise on Maritime Engineering. Third edition, with 24 plates. 8vo, cloth $9.00 STEWART, R. W. A Text Book of Light. Adapted to the Requirements of the Intermediate Science and Preliminary Scientific Examinations of the University of London, and also for General Use. Numerous Diagrams and Examples. 12mo, cloth, $1.00 A Text Book of Heat. Illustrated. 8vo, cloth... .$1.00 A Text-Book of Magnetism and Electricity. 160 nius. and Numerous Examples. 12mo, cloth $1.00 SCIENTIFIC PUBLICATIONS. 29 STILES, AMOS. Tables for Field Engineers. Designed for use in the field. Tables containing all the functions of a one degree curve, from which a corresponding one can be found for any required degree. Also, Tables of Natural Sines and Tangents. 12mo, morocco, tucks $2.00 STILliMAN, PAUL. Steam-Engine Indicator and the Improved Manometer Steam and Vacuum Gauges ; their Utility and Application. J^eic edition. 12mo, flexible cloth $1.00 STONE, General ROY. New Roads and Road Laws in the United States. 200 pages, with numerous illustrations. 12mo, cloth $1.00 STONEY, B. D. The Theory of Stresses in Girders and Similar Structures. With observations on the application of Theory to Practice, and Tables of Strength, and other propei-ties of Materials. New revised edition, with numerous additions on Graphic Statics, Pillars, Steel, Wind Pressure, Oscillating Stresses, Working Loads, Eiveting, Strength and Tests of Materials. 8vo, 777 pages, 143 illustrations, and 5 folding plates $12.50 STUART, C. B. U. S. N. Lives and Works of Civil and Military Engineers of America. With 10 steel-plate engravings. 8vo, cloth $5.00 The Naval Dry Docks of the United States. Illustrated vidth 24 fine Engravings on Steel. Fourth edition. 4to, cloth $6.00 SWEET, S. H. Special Report on Coal, showing its Distribution, Classification, and Costs delivered over different routes to various points in the State of New York and the principal cities on the Atlantic Coast. With maps. 8vo, cloth $3.00 SWINTON, ALAN A. CAMPBELL. The Elementary Principle of Electric Lighting. Illustrated. 12mo, cloth 60 TEMPLETON, WM. The Practical Mechanic's Work- shop Companion. Comprising a great variety of the most useful rules and formulae in Mechanical Science, with numerous tables of practical data and calculated results facihtating mechanical operations. Revised and enlarged by W. S. Hutton. 12mo, morocco $2.00 THOM, CHAS., and WILLIS H. JONES. Telegraphic Connections: embracing Recent Methods in Quadruplex Telegraphy. Oblong, Svo, cloth. 20 full page plates, some colored $1.50 THOMPSON, EDWARD P., M. E. How to Make In- ventions ; or. Inventing as a Science and an Art. A Practical Guide for Inventors. Second edition. Svo, boards $1.25 30 D. VAN N08TBAND COMPANY'S THOMPSON, EDWARD P., M. E. Roentgen Ivays and Phenomena of the Anode and Cathode. Principles, Applications and Theories. For Students, Teachers, Physicians, Photographers, Electricians and others. Assisted by Louis M. Pignolet, N. D. C. Hodges, and Ludwig Gutmann, E. E. With a Chapter on Generali- zations, Arguments, Theories, Kindred hadiations and Phenomena. By Professor Wm. Anthony. 8vo, cloth. 50 Diagrams, 40 Half tones $1.50 TODD, JOHN and W. B. WHALL. Practical Seaman- ship for Use in the Merchant Service : Including all ordinary sub- jects ; also Steam Seamanship, Wreck Lifting, Avoiding Collision, Wire Splicing, Displacement, and everything necessary to be known by seamen of the present day. Second edilion, witli 247 illustrations and diagrams. 8vo, cloth $8.40 TOOTHED GEARING. A Practical Hand-Book for Offices and Workshops. By a Foreman Patternmaker. 184 Hlustra- tions. 12mo, cloth $2.25 TRATMAN, E. E. RUSSELL. Railway Track and Track- Work. With over two hundred illustrations. Svo, cloth.$3.00 TRE VERT, EDWARD. How to build Dynamo-Electric Machinery, embracing Theory Designing and Construction of Dy- namos and Motors. With appendices on Field Magnet and Armature Winding, Management of Dynamos and Motors, and Useful Tables of Wire Gauges. Illustrated. Svo, cloth $2.50 Electricity and its Recent Applications. A Practi- cal Treatise for Students and Amateurs, with an Illustrated Dictionary of Electrical Terms and Phrases. Illustrated. 12mo, cloth . . $2. 00 TUCKER, Dr. J. H. A Manual of Sugar Analysis, in- cluding the Applications in General of Analytical Methods to the Sugar Industry. With an Introduction on the Chemistry of Cane Sugar, Dextrose, Levulose, and Milk Sugar. Svo, cloth, illus- trated $3.50 TUMLIRZ, DR. O. Potential and its Application to the Explanation of Electric Phenomena, Popularly Treated. Trans- lated from the German by D. Eobertson. 111. 12mo, cloth. . . .$1.25 TUNNER, P. A. Treatise on Roll-Turning for the Manufacture of Iron. Translated and adapted by John B. Pearse. of the Pennsylvania Steel Works, with numerous engravings, woodcuts. Svo, cloth, with folio atlas of plates $10.00 URQUHART, J. W. Electric Light Fitting. Embody- ing Practical Notes on Installation Management. A Hand-book for Working Electrical Engineers — with numerous illustrations. 12mo, cloth $2.00 Electro-Plating. A Practical Hand Book on the Deposition of Copper, Silver, Nickel, Gold, Brass, Aluminium, Plat- ininum, etc. Third edition, 12mo $2.00 SCIENTIFIC PUBLICATIONS. 31 URQUHART, J. "W. Electrotyping. A Practical Man- ual forming a New and Systematic Guide to the Beproduction and Multiplication of Printing Surfaces, etc. 12mo $2.00 Dynamo Construction: a Practical Hand-Book for the Use of Engineer Constructors and Electricians in Charge, em- bracing Frame Work Building, Field Magnet and Armature Winding and Groviping, Compounding, etc.. with Examples of Leading Eng- lish, American and Continental Dynamos and Motors, with numerous illustrations. 12mo, cloth $3.00 Electric Ship Lighting. A Hand-Book on the Practical Fitting and Running of Ship's Electrical Plant. For the Use of Ship Owners and Builders, Marine Electricians and Sea Going Engineers-in-Charge. Numerous illustrations. 12mo, cloth $3.00 UNIVERSAL TELEGRAPH CIPHER CODE. Ar- ranged for General Correspondence. 12mo, cloth $1.00 VAKT HEXJRCK, Dr. HENRI. The Microscope, Its Construction and Management, including Technique, Photo-Micro- graphy and the Past and Future of the Microscope. English edition re-edited and augmented by the Author from the fourth French edition, and translated by Wynne E. Baxter, F.B.M.S. 3 Plates and upwards of 250 Illustrations. Imperial 8vo, cloth $7.00 VAN NOSTRAND'S Engineering Magazine. Com- plete sets, 1869 to 1 886 inclusive. Complete sets, 35 vols., in cloth $60.00 Complete sets, 35 vols. , in half morocco 100.00 VAN WAGENEN, T. F. Manual of Hydraulic Mining. For the Use of the Practical Miner. li< vised niid cnlnrgccl edHion. 18mo, cloth $1-00 WALKER, W. H. Screw Propulsion. Notes on Screw Propulsion, its Else and History. 8vo, cloth 75 WALKER, SYDNEY F. Electrical Engineering in Our Homes and Workshops. A Practical Treatise on Auxiliary Elec- trical Apparatus. Third edition, revised, ivitli ntuiicrovs iUiistra- tions ^2.00 Electric Lighting for Marine Engineers, or How to Light a Ship by the Electric Light and How to Keep the Apparatus in Order. 103 illustrations. 8vo, cloth. SeeotuI edition $2.00 WALLIS-TAYLER, A. J. Modem Cycles^ A Practi- cal Handbook on Their Construction and Rf pair. With 300 illustra- tions. 8vo, cloth t*-00 Motor Cars, or Power Carriages for Common Boads. 8vo, cloth, with numerous illustrations $1.80 Bearings and Lubrication. A Handbook for every user of Machinery. 8vo, cloth, fully illustrated $1.50 32 D. VAN NOSTBAND COMPANY'S WALLiIS-TAYLER, A. J. Refrigerating and Ice- Making Machinery. A Descriptive Treatise for the use of persons employing refrigerating and ice-making installations and others. 8vo, cloth, illustrated .., $3.00 Sugar Machinery. A Descriptive Treatise, De- voted to the Machinery and Apparatus used in the Manufacture of Cane and Beet Sugars. 12mo, cloth, ill $2.00 "WANKLYN, J. A. A Practical Treatise on the Exam- ination of Milk and its Derivatives, Cream, Butter, and Cheese. 12mo, cloth $1.00 Water Analysis. A Practical Treatise on the Ex- amination of Potable Water. Tenth edition. 12mo, cloth $2.00 WANSBROUGH, WM. D. The A. B. C. of the Differ- ential Calculus. 12mo, cloth .' $1.50 WARD, J. H. Steam for the Million. A Popular Treat- ise on Steam, and its application to the Useful Arts, especially to Navigation. 8vo, cloth $1.00 WARING, GEO. E., Jr. Sewerage and Land Drainage. Illustrated with wood-cuts in the text, and full-page and folding plates. Quarto. Cloth. Third edition $6.00 Modem Methods of Se-vsrage Disposal for Towns, Public Institutions and Isolated Houses. Second edition, revised and enlarged. 260 pages. Illustrated, cloth $2.00 How to Drain a House. Practical Information for Householders. New and enlarged edition.] 12mo, cloth $1.25 WATSON, E. P. Small Engines and Boilers. A man- ual of Concise and Specific Directions for the Construction of Small Steam Engines and Boilers of Modern Types from five Horse-power down to model sizes. 12mo, cloth. Illustrated with Numerous Diagrams and Half Tone Cuts. New York, 1899 $1.25 WATT, ALEXANDER. Electro-Deposition. A Prac- tical Treatise on the Electrolysis of Gold, Silver, Copper, Nickel, and other Metals, with Descriptions of Voltaic Batteries, Magneto and Dynamo-Electric Machines, Thermopiles, and of the Materials and Processes used in every Department of the Art, and several chapters on Electro-Metallurgy. With numerous illustrations. Third edition, revised and corrected. Crown, Svo, 568 pages $3.50 Electro-Metallurgy Practically Treated. Tenth edition, considerably enlarged. 12mo, cl $1.00 The Art of Soap-Making. A Practical Handbook of the Manufacture of Hard and Soft Soaps, Toilet Soaps, &c. In- cluding many New Processes, and a Chapter on the Eeooveiy of Glycerine from Waste Lyes. With illustrations. Fourth edition, revised and enlarged. Svo $3.00 SCIENTIFIC PUBLICATIONS. 33 WATT, ALEXANDER. The Art of Leather Manufact- ure. Being a Practical Handbook, in which the Operations of Tan- ning;, CnrryiuR, and Leather Dressing are Fully Described, and the Prmciplcs of Tanning Explainod, and many Recent Processes Intro- duced. With numerous illustrations. Sc<-t>n(l aUtion. 8vo, cl.$4.00 WE ALE, JOHN. A Dictionary of Terms Used in Architecture, Building, Engineering, Mining, Metallurgy, Archaelogy, the Fine Ai-ts, etc., with explanatory obsei-vat-ons connected witli applied Science and Art. fifth edition, rcvifscd and mrrvctcd. 1.2mo, cloth $2.50 Weale's Rudimentary Scientific Series, [see list, p. 39. J WEBB, HERBERT LAWS. A Practical Guide to the Testing of Insulated Wires and Cables. Illustrated. 12rao, cloth $1.00 The Telephone Hand Book. Ii8 illustrations. 146 pages. 16mo., cloth $1.00 WEEKES, R. W. The Design of Alternate Current Transformers. Illustrated. 12mo, cloth $1.00 WEISBACH, JULIUS. A Manual of Theoretical Mechanics. Eighth American edition. Translated from the fourth augmented and improved German edition, with an Introduction to the Calculus by Eckley B. Coxe, A.M., Mining Engineer. 1,100 pages, and 902 woodcut illusti-ations. 8 vo, cloth $6.00 Sheep 7.50 WESTON, EDMUND B. Tables Showing Loss of Head Due to Friction of Water in Pipes. ,Si i-i>}id cililioit. ]2mo, cloth $1.50 WEYMOUTH, F. MARTEN. Drum Armatures and Commutators. (Theory and Practice.) A complete Treatise on the Theory and Construction of Drum Winding, and of commutators- for closed-coil armatures, together with a full resume of some of the prin- cipal points involved in their design, and an exposition of armature re-actions and sparking. Svo, cloth $3.00 WEYRAUCH, J. J. Strength and Calculations of I Dimensions of Iron and Steel Construction, with reference to the j Latest Experiments. 12mo, cloth, plates $1.00 WHEELER, Prof, J. B. Art of War. A Course of Instruction in the Elements of the Art and Sciciico of War, for the Use of the Cadi'ts of the United State,", iMilitaiy Academy, West Point, N. Y. 12mo, cloth $1.75 Field Fortifications. The Elements of Field Fortifications, for the Use of the Cadets of th<^ TTnited States Military Academy, West Point, N. Y. 12mo $1.75 34 D. VAN NOSTEAND GO'S SCIENTIFIC PUBLICATIONS. WHIPPLE, S., C. E. An Elementary and Practical Treatise on Bridge Building. 8vo, cloth $3.00 WILKINSON, H. D. Submarine Cable-Laying, Re- pairing and Testing. 8vo, cloth $4.00 WILLIAMSON, R. S. On the Use of the Barometer on Surveys and Beconnoissances. Part I. Meteorology in its Connection with Hypaometry. Part II. Barometric Hypsometry. With Illus- trative tables and engravings. 4to, cloth $15.00 Practical Tables in Meteorology and Hsrpsometry, in connection with the use of the Barometer. 4to, cloth $2.50 WILSON, GEO. Inorganic Chemistry, with New No- tation. Eevised and enlarged by H. G. Madan. New edition. ]2mo, cloth $2.00 WILL YOUNG, E. G., and W. M. STONE, Ph. D. Elec- trical Instruments and Measurements. 12mo, cl. 2 vols — In Press. WOODBURY, D. V. Treatise on the Various Elements of stability in the Well-Proportioned Arch. 8vo, half morocco.. $4. 00 WRIGHT, T. W. A Treatise on the Adjustment of Observations. With applications to Geodetic Work, and other Meas- ures of Precision. 8vo, cloth $4.00 Elements of Mechanics ; including Kinematics, Kinetics and Statics. With applications. 8vo, cloth $2.50 WYLIE, CLAUDE. Iron and Steel Founding. Illus- trated with 39 diagrams. Second edition, revised and enlarged. 8vo, cloth $2.0. WYNKOOP, RICHARD. Vessels and Voyages, as Regulated by Federal Statutes and Treasury Instructions and Decis- ions. 8vo, cloth $2.00 YOUNG, J. ELTON. Electrical Testing for Telegraph Engineers, with Appendices consisting of Tables. 8vo, cloth, illus- trated $4.00 YOUNG SEAMAN'S MANUAL. Compiled from- Various Authorities, and Illustrated with Numerous Original and Select Designs, for the Use of the United States Training Ships and the Marine Schools. 8vo, half roan $3.00 Catalogue of the Van Nostrand Science Series. 7*HE J ' are put up in a uni/orjii, neat, and attractive form. iSma, hoards. Price JO cents per volume. The subjects are of an eminently scientific character, and embrace a wide range of topics, and are amply illustrated when the subject demands. No. I. CHIMNEYS FOR FURNACES AND STEAM BOILERS. By R. Armstrong, C. E. Third American edition, revised and partly rewritten, with an appendix on Theory of Chimney Draught, by F. E. Idell, M.E. No. 2. STEAM-BOILER EXPLOSIONS. By Zerah Colburn. Nsw edition, revised by Prof. R. H. Thurston. No. 3. PRACTICAL DESIGNING OF RETAINING- WALLS. By Arthur Jacob, A.B. Second edition, revised, with additions by Prof. W. Cain. No. 4. PROPORTIONS OF PINS USED IN BRIDGES. Second edition, with appendix. By Charles E. Bender, C.E. No. 5. VENTILATION OF BUILDINGS. By VV. F. Butler. Second edition, re-edited and enlarged by James L. Greenleaf, C.E. No. 6. ON THE DESIGNING AND CONSTRUCTION OF STORAGE RESERVOIRS. By Arthur Jacob, A.B. Second edition, revised, with additions by E. .Sherman Gould. No. 7. SURCHARGED AND DIFFERENT FORMS OF RE- TAINING-WALLS. By James S. Tate, C.E. No. 8. A TREATISE ON THE COMPOUND ENGINE. By John Turnbull, jun. Second edition, revised by Prof. S. \V. Robinson. No. 9. A TREATISE ON FUEL. By Arthur V. Abbott, C. E. Founded on the original treatise of C. William Siemens, D.C.L. No. 10. COMPOUND ENGINES. Translated from the French of A. Mallat. Second edition, revised, with Results of American Practice, by Richard H. Buel, C.E. No. II. THEORY OF ARCHES. By Prof. W. Allan. No. 12. A THEORY OF VOUSSOIR ARCHES. By Prof. W. E. Cain. Second edition, revised and enlarged. lUustratad. No 13. GASES MET WITH IN COAL-MINES. By J. J. A tkinsoa Third edition, levised and enlarged by Edward M ^Villiams, jun. D. VAI\' NOSTRAND CO.tfPAIs'Y'S No. 14. FRICTION OF AIR IN MINES. By J. J. Atkinson, No. 15. SKEW ARCHES. By Prof. E. W. Hyde, C.E. Illustrated. No. 16. A GRAPHIC METHOD FOR SOLVING CERTAIN ALGEBRAIC EQUATIONS. By Prof. George L. Vose. No. 17. WATER AND WATER-SUPPLY. By Prof. W. H. Corfield of the University College, London. No. 18. SEWERAGE AND SEWAC^ PURIFICATION. By M. N. Baker, Assoc. Ed. Engiiuci-itig Aews. No. 19. STRENGTH OF BEAMS UNDER TRANSVERSE LOADS. By Prof. W. Allan, author of "Theory of Arches." No. 20. BRIDGE AND TUNNEL CENTRES. By John B. Mc Master, C.E. No. 21. SAFETY VALVES. By Richard H. Buel, C.E. Second edition. No 22. HIGH MASONRY DAMS. By E. Sherman Gould, C.E. No. 23. THE FATIGUE OF METALS UNDER REPEATED STRAINS. With Various Tables of Results and E.xpernne:its. From the German of Prof. Ludwig Spangenburgh, with a Preface by S. il. Shreve, A.M. No. 24. A PRACTICAL TREATISE ON THE TEETH OP WHEELS. By Prof. S. W. Robinson. Second edition, revised. No. 25. ON THE THEORY AND CALCULATION"' OF CAN- TILEVER BRIDGES. By R. M. Wilcox, Ph.B. No. 26. PRACTICAL TREATISE ON THE PROPERTIES OF CONTINUOUS BRIDGES By Charles liender, C E. N0.-27. ON BOILER INCRUSTATION AND CORROSION By F. J. Rowan. New edition, revised and partly rewritten by F. E. Ideli, M. E. No. 28. TRANSMISSION OF POWER BY WIRE ROPES By Albert W. Stahl, U.S.N. Second edition. No. 29. STEAM INJECTORS. Translated from the French 01 M. Leon Pochet. No. 30. TERRESTRIAL MAGNETISM, AND THE MAGNET. ISM OF IRON VESSELS. By Prof. Fainnan Rogers. Ko. 31. THE SANITARY CONDITION OF dWeLLING- HOUSES IN TOWN AND COUNTRY. By George E. Waring, jun, No. 32. CABLE-MAKING FOR SUSPENSION BRIDGES. By W. Hildenbrand, C.E. No. 33._ MECHANICS OF VENTILATION. By George W. Rafter, C.E. New edition (1895), revised by aiithor. No. 34. FOUNDATIONS. By Prof. Jules Gaudard, C.E. Translated from the French. No. ■^s. THE ANEROID BAROMETER: ITS CONSTRUC TION AND USE. Compiled by George W. Plympton. Fourth edition No. 36 MATTER AND MOTION. By J. Clerk Maxwell, M.A. .Second American edition. SCIENCE SERIES. fjo. 37. GEOGRAPHICAL SURVEYING: ITS USES, METH- ODS, AND RESULTS. By Frank De Yeaux Carpenter, C.E. No. 38. MAXIMUM STRESSES IN FRAMED BRIDGES. By Prof. William Cain, A.M., C.E. New and revised edition. No. 39. A HANDBOOK OF THE ELECTRO-MAGNETIC TELEGRAPH. By A. E. Loring. No. 40. TRANSMISSION OF POWER BY COMPRESSED AIR. By Robert Zahner, M.E. Second edition. No. 41. STRENGTH OF MATERIALS. By William Kent, C.E., Assoc, Ed. Engineering News. No. 42. VOUSSOIR ARCHES APPLIED TO STONE BRIDGES, TUNNELS, CULVERTS, AND DOMES. By Prof. William Cain. No 43. WAVE AND VORTEX MOTION. By Dr. Thomas Craig of Johns Hopkins University. No. 44. TURBINE WHEELS. By Prof. W. P. Trowbridge, Columbia College. Second edition. No. 45. THERMODYNAMICS. By Prof. H. T. Eddy, University cl Cincinnati. No. 46. ICE-MAKING MACHINES. New edition, revised and en- larged by Prnf. I. E. Denton. From the French of M. Le Doux. No. 47. LINKAGES; THE DIFFERENT FORMS AND USES OF ARTICULATED LINKS. By J. D. C. de Roos. No. 48. THEORY OF SOLID AND BRACED ARCHES. By William Cain, C.E. No. 49. ON THE MOTION OF A SOLID IN A FLUID. By Thomas Craig, Ph.D. No. 50. DWELLING-HOUSES : THEIR SANITARY CON- STRUCTION AND ARRANGEMENTS. By Prof. W. H. Corfield. No. 51. THE TELESCOPE . ITS CONSTRUCTION, ETC. By Thomas Nolan. No. 52. IMAGINARY QUANTITIES. Translated from the French of M. Argand. By Prof. Hardy. No. 53. INDUCTION COILS: HOW MADE AND HOW USED. Fifth edition. No. 54. KINEMATICS OF MACHINERY. By Prof. Kennedy. With an introduction by Prof. R. H. Thurston. No. ss. SEWER GASES: THEIR NATURE AND ORIGIN. By A. de Varona. No. 56. THE ACTUAL LATERAL PRESSURE OF EARTH- WORK. By Benjamin Baker, M. Inst C.E. No. S7- INCANDESCENT ELECTRIC LIGHTING. A Practical Description of the Edison System. By L. H. Latimer, to which is added the Design and Operation of Incandescent Stations, by C. J. Field, and the Maximum Efliciency of Incandescent Lamps, by John W. Howell. No. 58. THE VENTILATION OF COAL-MINES. By W. Fairley. M.E, F.S.S. D. VAN NOSTRAND COMPANY'S No. 59. RAILROAD ECONOMICS; OR, NOTES, WITH COM- MENTS. By S. W. Robinson, C.E. No. 60. STRENGTH OF WROUGHT-IRON BRIDGE MEM- BERS. By S. W. Robinson, C E. No. 61. POTABLE WATER AND METHODS OF DETECT- ING IMPURITIES. By M. N. Baker, Ph.B. No. 62. THE THEORY OF THE GAS-ENGiNE. By Dugald Clerk. Second edition. With additional matter. Edited by F. E. Idell, M.E. No. 63. HOUSE DRAINAGE AND SANITARY PLUMBING. By W. P. Gerhard. Seventh edition, revised. No. 64. ELECTRO-MAGNETS. ByTh.du Moncel. 2d revised edition. No. 65. POCKET LOGARITHMS TO FOUR PLACES OF DECI- MALS. No. 66. DYNAMO-ELECTRIC MACHINERY. By S. P. Thompson, With notes by F. L. Fope. Third edition. No. 67. HYDRAULIC TABLES BASED ON " KUTTER'S FORMULA." By P. J, Flynn. No. 68. STEAM-HEATING. By Robert Briggs. Second edition, revised, with additions by A. R. Wolff. No. 69. CHEMICAL PROBLEMS. By Prof. J. C. Foye. Fourth edition, revised and enlarged. No. 70. EXPLOSIVE MATERIALS. The Phenomena and Theories of Explosion, and the Classification, Constitution and Preparation of Explosives. By First Lieut. John P. Wisser, U.S.A. No. 71. DYNAMIC ELECTRICITY. By John Hopkinson, J. A. Schoolbred, and R. E. Day. No. 72. TOPOGRAPHICAL SURVEYING. By George J. Specht. Prof. A. S. Hardy, John B. McMaster, and H. F. Walling. No. 73. SYMBOLIC ALGEBRA; OR, THE ALGEBRA OF ALGEBRAIC NUMBERS. By Prof. W. Cain. No. 74. TESTING MACHINES : THEIR HISTORY, CON- STRUCTION, AND USE. By Arthur V. Abbott. No. 75. RECENT PROGRESS IN DYNAMO-ELECTRIC MA- CHINES. Being a Supplement to Dynamo-Electric Machinery. By Prof. Sylvanus P. Thompson. No. 76. MODERN REPRODUCTIVE GRAPHIC PROCESSES. By Lieut. James S. Pettit, U.S.A. No. 77. STADIA SURVEYING. The Theory ot Stadia Measurements. By Arthur Winslow. No. 78. THE STEAM-ENGINE INDICATOR, AND ITS USE By W. B. Le Van. No. 79. THE FIGURE OF THE EARTH. By Frank C. Roberts, C.E. No. 80. HEALTH V Ft)UNDATIONS FOR HOUSES. By Glenn Brown SCIENCE SERIES. No. 8i. WATER METERS : COMPARATIVE TESTS OF ACCURACY, DELIVKKY, ETC. Di.-tinctive features of the Worth- ington, Kennedy, Siemens, and Hcsbc meters. By Ross E. Browne. No. 8a. THE PRESERVATION OF TIMBER BY THE USE OF ANTISEPTICS. By Samuel Bagster Boulton, C.E. No. 83. MECHANICAL INTEGRATORS. By Prof. Henry S. H. Shaw, C.E. No 84. FLOW OF WATER IN OPEN CHANNELS, PIPES, CONDUITS, SEWERS, ETC. With Tables. By P. J. Flynn, C.E. No. 85 THE LUMINIFEROUS iETHER. By Prof, de Volson Wood. No 86 HAND-BOOK OF MINERALOGY; DETERMINATION ' AND DESCRIPTION OF MINERALS FOUND IN THE UNITED STATES. By Prof. J. C. Foye. No. 87. TREATISE ON THE THEORY OF THE CON- STRUCTION OF HELICOIDAL OBLIQUE .\RCHES. By John L. Culley, C.E. No. 88. BEAMS AND GIRDERS. Practical Formulas for their Re- sistance. By P. H. Philbrick. No. 89. MODERN GUN-COTTON: ITS MANUFACTURE, PROPERTIES, AND ANALYSIS. By Lieut. John P. Wisstr, U.S.A. No. 90. ROTARY MOTION, AS APPLIED TO THE GYRO- SCOPE. By Gen. J. G. Barnard. No. 91. LEVELING: BAROMETRIC, TRIGONOMETRIC, AND SPIRIT. By Prof. I. O. Baker. No. 92. PETROLEUM : ITS PRODUCTION AND USE. By Boverton Redwood, F.I.C., F.C.S. No. 93. RECENT PRACTICE IN THE SANITARY DRAIN- AGE OF BUILDINGS. With Memoranda on the Cost of Plumbing Work. Second edition, revised. By William Paul Gerhard, C. E. No. 94. THE TREATMENT OF SEWAGE. By Dr. C. Meymott Tidy. No OS. PLATE GIRDER CONSTRUCTION. By Isami Iliroi, C.E. Second edition, revised and enlarged. Plates and Illustrations. No. 96. ALTERNATE CURRENT MACHINERY. By Gisbert Kapp, Assoc. M. Inst., C.E. No 07 THE DISPOSAL OF HOUSEHOLD WASTE. By W Paul Gerhard, Sanitary Engineer. N„ „R PRACTICAL DYNAMO-BUILDING FOR AMATEITRS. 'nbw TO WIND FOR ANY OUTPUT By Frederick Walker. Fully illustrated, fti „„ TRIPLE-EXPANSION ENGINES AND ENGINE ^ ^RIAlI By Prof. Osborne Reynolds. Edited, with notes, etc., by F. E. Idell. M. E. SCIENCE SERIES. No. 100. HOW TO BECOME AN ENGINEER ; OR, THE THEORETICAL AND PRACTICAL TRAINING NECESSARY IN FITTING FOR THE DUTIES OF THE CIVIL ENGINEER. The Opinions of Eminent Authorities, and the Course of Study in the Technical Schools. By Geo. W. Plyrapton, Am. Soc. C.E. No. loi. THE SEXTANT AND OTHER REFLECTING MATHEMATICAL INSTRUMENTS. With Practical Suggestions and Wrinkles on their Errors, Adjustments, and Use. With thirty- three illustrations. By F. R. Brainard, U.S.N. . No. 102. THE GALVANIC CIRCUIT INVESTIGATED MATHEMATICALLY. By Dr. G. S. Ohm, Berlin, 1827. Translated by William Francis. W.-h Preface and Notes by the Editor, Thomas D. Lockwood, M.I.E.E. No. 103. THE MICROSCOPICAL EXAMINATION OF POTA- BLE WATER. With Diagrams, By Geo. W. Rafter. ■^o. 104. VAN NOSTRAND'S TABLE-BOOK FOR CIVIL AND MECHANICAL ENGINEERS. Compiled by Geo. W. Plympton, C.E, No. 105. DETERMINANTS, AN INTRODUCTION TO THE STUDY OF. With examples. By Prof. G. A. Miller. No. 106. TRANSMISSION BY AIR-POWER. Illustrated. By Prof. A. B. W. Kennedy and W. C. Unwin. No. 107. A GRAPHICAL METHOD FOR SWING-BRIDGES. A Rational and Easy Graphical Analysis of the Stresses in Ordinary Swing-Bridges. With an Introduction on the General Theory of Graphi- cal Statics. 4 Plates. By Benjamin F. LaRue, C.E. No. 108. A FRENCH METHOD FOR OBTAINING SLIDE- VALVE DIAGRAMS. 8 Folding Plates. By Lloyd Bankson, B.S., Assist. Naval Constructor, U.S.N. No. 109. THE MEASUREMENT OF ELECTRIC CURRENTS. Electrical Measuring Instruments. By Jas. Swinburne. Meters FOR Electrical Energy. By C. H. Wordingham. Edited by T. Coramerford Martin. Illustrated. No. no. TRANSITION CURVES. A Field Book for Engineers, containing Rules and Tables for laying out Transition Curves By Walter G. Fox. No. III. GAS-LIGHTING AND GAS-FITTING, including Specifica- tions and Rules for Gas Piping, Notes on the Advantages of Gas for Cooking and Heating, and useful Hints to Gas Consumers. Second edition, rewritten and enlarged. By Wm. Paul Gerhard. No. 112. A PRIMER ON THE CALCULUS. By E. Sherman Gould, C.E. No. 113. PHYSICAL PROBLEMS AND THEIR SOLUTION. By A. Bourgougnon, formerly Assistant at Bellevue Hospital. No. 114. MANUAL OF THE SLIDE RULE. By F. A. Halsey of the American Machinist.