I I ^ TREATISE ON THE CULTURE, PREPARATION, HISTORY, AND ANALYSIS OP PASTEIL, OR WOAB2 THE DIFFERENT METHODS OF EXTRACTING THE COLORING MATTER, AND ^ THE MANNER OF USING IT, AND INDIGO, IN DYEING. BY C. P. DE LASTEYRIE. TO WHICH IS ADDED, INFORMATION UPON THE ART OF EXTRACTING INDIGO, FROM THE LEAVES OF PASTEL, PUBLISHED BY ORDER OF HIS EXCELLENCY, MONTALIVET, Count of the Empire, Minister of the Interior. PARIS.. •.1811, Naturellement sans moyen, le Pastel fait la couleur bleue..,.. De lui^meme aussi seul causant de celestes couleurs eomme plus ou moins charge. OLIVIER DE SERRES, TRANSLATED FROM THE FRENCH, BY H. A. S. DEARBORN. BOSTON : PRINTED BY ROWE & HOOPER.,..78, StateStreei. 1816. TABLE OF CHAPTERS. PART FIRST. Culture and Preparation of Fastet CHAPTER L Page Description of Pastel 13 CHAPTER n. Proper soil for Pastel^ and the manure suitable for it - - - - - 16 CHAPTER m. The seedp the time^ and manner of sowing it IS IV Page CHAPTER IV. The necessary labor during the growth of Pastel 23 CHAPTER V. Diseases and Insects which attack Pastel 23 CHAPTER VL Manner of procuring the Seed - . 24 CHAPTER Vn. Succession of Crops to follow in the culture of Pastel . - - - 25 CHAPTER VHL Pastel considered as Fodder » - 27 CHAPTER IX. Harvest of Pastel « . . 29 CHAPTER X. Of the Grinding and Preparation of Pastel CHAPTER XL The Storage of Pastel CHAPTER Xn. The Culture and Preparation of Pastel in England « . - * PART SECOND. HISTORY OF PASTEL^ ANALYSIS AND EXTRACTIOH OF THE FLOCCULI. CHAPTER L Page Mstonj of Pastel - ... 00 CHAPTER n. Analysis of Pastel [Isatis tinctoria L.) and of its coloring Flocculi « - • 77 CHAPTER HL Different processes which have been employ- ed to contract Indigo from Pastel - 9§ CHAPTER IV. The use of Indigo and Pastel in Dyeing 106 Page Information on the Art of Extracting Indigo from the Leaves of Pastel - - 127 Extraction of Indigo from the Leaves of Pastel 133 Selection of the Leaves - - - ibo^ Fermentation of the Leaves of Pastel 134 Precipitation of the Indigo - - 136 Separation of the Indigo from the yellow matter 137 Drying of the Indigo » ^ » - 18Sf ERR4TA. in the preface, for Chinese^ read Ckinenst. „ fa^o pirum, read Fagopyrum, „ Hedris-arium^ read H&dysarum, Cicerarietinam^ read Cicer Arietinum. Gemp;5a, read Gtnipa^ „ Polygola^ read Polygala. „ Chilidoniummagm^ read Chelidonium majus. „ futicasa read fruticosa, „ Agoricus^ read Agaricus. „ Cablab^ read Lablab. In note at page 126 „ jRe5od!a-Ott/eo/a, read i^e*erfa Xu/eo^a. ^, welob^ read i^'cZfi. THANSLATOR^S PREFACE. During the system of continental restrictions^ which excluded the marine importation of the pro- ducts of every other country into France^ vast ex- ertions were made to replace by those of that na- tion^ such as usually had been imported from oth- er parts of the world. Indigo had been for the last century and a half;, the only pigment used for dyeing blue^ and a sub- stitute was rendered indispensable. High premiums were oflered by the Emperor^ for the discovery of some indigenous substance^ which would supply its place. Enquiry was universally excited ; experiments were made upon a variety of plants^ and from the researches of the savans^ it was ascertained that pure indigo could be extracted from Polygonum tinctorktm^ Chinese^ barbatum^ aviculare^ and fa- go pirum ; Galega tinctoria^ Hedris-arium^ ^^ff^'^- ent species ; Cicerarietinum^ common ciches^ or X cTiick-fea; Medicago sativa, Lucerne^ or purple medicJc ; Scabiosa succisa^ VeviVs hit ; Mercuri- alis perennis^ IJogs mercury ; Vaccinium myr- tilluS;, Robinia caragana^ a Siberian shrub ; Cen- taurea cyanus^ Blue bottle ; Grenippa Americana^ Polygola^ Milk-wort ; Sopliora tinctoria^ Spilan- thus tinctoriiis^ Acer rubrum, a species of the ma- ple; Lotus corniculatus^ Birds-foot trefoil^ or milk- vetch ; Lignum nephreticum^ Guilandina morin- ga^ a wood of South America ; Inula helenium^ elecampane ; Cica^ Chilidonium magus^ common Celandine ; Quercus^ Oaky the heart of various species / Sambucus nigra and ebulus, Coronilla futicasa^ Agoricus campestris, Mushroom^ or Champignon ; Oestrum tinctorium^ Lichen^ i2te- merous species ; Dolichos Cablab^ Egyptian kid- ney bean ; and Isatis tinctoria, Pastel^ or woad. Isatis tinctoria^ was found to yield the greatest quantity of coloring matter ; could be cultivated all over France ; required less trouble and ex- pense in the culture and preparation than any other plant; and dyed as beautiful, deep, and as permanent a color, as the best India indigo. The most celebrated chymists of that nat. jn, bestovred great attention on the analysis of pastel ; numerous experiments were made to discover the best mode of cultivation, and various processes were attempted for extracting the coloring flocculi. xi Joel Barlow, Esq. was Minister of the United States at the French Court, during the time these enquiries and experiments were made. He was deeply impressed with the importance which the cultivation of woad would be to his country, and transmitted these publications to one of his friends in Connecticut, who loaned them to the translator, with his consent that they should be translated for the press. There is not a doubt but that woad can furnish a blue pigment for all the States, where indigo cannot be cultivated at a cheaper rate than they are now supplied with that coloring ingredient. The translator received, three years since, about an hundred woad seeds, which were sown in drills, and the second year he gathered three bushels of seed from the plants. The plants were not in the smallest degree in- jured by the frosts of winter, and vegetated much earlier in the spring than those which were natives of our soil. The seed stalks had grown many inches, before the grass had even sprouted. At that time no treatise on the mode of cultiva- tion, or the methods of preparing the leaves into pelotes, or of extracting the indigo, had been seen. The only object in publishing this work, is the advancement of our agricultural and manufactur- ing interests. If a disposition is excited to make experiments on the culture and use of woad, as a xu dying ingredient, wliich sliall ultimately be pro- ductive of beneficial effects, the translator will be amply compensated, in the reflection, that he may have been of some service to his country. He will be happy to furnish seed to such per- sons as may be inclined to attempt the cultivation of woad, and will send it to them with pleasure, in such manner as they may point out. BRINLEY PLACE, MAY, 1816. PASTEL. PART FIRST, CULTURE AND PREPARATION OF PASTEL CHAPTER L DESCRIPTION OF PASTEL. Pastel is also called guede and vouede^ and/by our ancient authors^ guesde^ guide,, giierdes^ garde ; these last denominations are derived from the Cel- tic word glastum^ or guastiim^ adopted by the Ro- mans. The Germans describe it under the name of waidy or that of pastel ; the English under that of woad ; the Italians under those of guado^guaL do^ glastOj jpastello ; the Spaniards, giiasto^ and pastel ; ihe Botanical name is isatis tinctoria. L. The name of pastel is derived from the words^ pelotes^ or pastilles^ because, in preparing it, they give the form indicated by these denominations, S 14 Pastel is sometimes confounded with gaiide. ov vaiide. The last is a very different plant^ employ- ed in coloring yellow^ &c. known by Botanists by the namB of reseda luteola. L. The following are the Botanical characteristics by which pastel is known. Root. Fusiform;, fibrous, ligneous, and from twelve to fifteen inches in length. Stalk. From three and a half to six feet high. It is branchy, smooth, and bears on its summit a great number of flowers, disposed in panicles. Leaves, Those of the root are oval, oblong, petioled, carneous, from twelve to fifteen inches long. Those of the stalk are large, lanceolate, alternate ; both are of a dark blueish, green color. Flowers. The calyx is composed of four oval leaflets, edged, rather expanded, colored and de- ciduous ; ihe corolla has four oblong, obtuse, ex- panding, cruciform petals, of a yellow color, grad- ually attenuated into claws ; the stamens are six in number, four of which are longer than the other two ; the anthers are oblong and lateral ; the ova- rie, or germ, is oblong, compressed, and of the length of the two shortest stamens ; a very short style, inclosed, in part, in the superior portion of the valves, terminated by an obtuse stigma, in the form of a head. Fruit. A small silicle, of a deep blue, oval, lanced, ^ oblong, obtuse, compressed, two edged, one celled, two valved, with an elevation in the middle ; the two valves not easily separated, and which contain, in the centre of the pericarp, an oval, egg-shaped seed. The pastel or woad, cultivated in Normandy, 15 appears to be a little different from that of Alby. It is^ perhaps, a variety. It is much more feeble in color. The dyers make much less use of this ; they do not use it, except with the pastel of Lan- guedoc, to renew it^ as they express it. This in- Priority of quality clearly results from the climate where it is cultivated. There are some other kinds and varieties, of pastel, upon which no experiments have been made by dyers, and which may, notwithstanding, pos- sess some advantages. Such, for example, as the isaiis alpina^ L. which g^ows, naturally, upon mount Vesaul, in steep or rugged dry places. Its leaves are smaller than the common pastel ; but as the most sterile soil is congenial to it, it can be cultivated with success, under certain circumstan- ces, particularly as forage for cattle, if this species of plant should be found to answer that purpose. \There is found in the neighborhood of Paris, and in other parts of Europe, a variety, whicii diflers a little from this. Cultivators should be acquainted with another kind of pastel, commonly designated under the name of bastard pastel^ and under that of hoiirg^ or hourdaine^ in Lauragai. It has hairy leaves^ while that of the true pastel are very smooth ; the seeds of this kind are of a dark violet, those of the first are yellow. The bastard pastel is of an inferior quality, and has another disadvantage, that of retaining the dust and earth, which deteri- orates the colorins: flocculi* 16 CHAPTER IL Of the proper soil for Pastel; its preparation, and the manure suitable for it. Pastel grows naturally in dry, stony land, on mountains, and in moist bottoms or intervals. It can be cultivated on difierent kinds of soil ; but its quality, and the produce depends on the nature of the soil on which it grows. If it is raised on a dry, light, and barren soil, but a small crop will be obtained ; possessing but a little coloring floc- culi ; if upon a fat, moist, clayey soil, the leaves, although very abundant, contain a greater propor- tion of sap, than of the coloring flocculi. Too much moisture injures the plant, particu- larly when this moisture beconjes habitual, in con- sequence of an inferior stratum, which naturally obstructs the regular escape of the water. The choice of the soil is, therefore, very important, for if judiciously chosen, the crops will be double and of a superior quality. A soil of a mean consistence is to be preferred, rather clayey than sandy ; fat, rich, w arm and not very moist. If it is too light, it can be improved with compost or a mixture of earths. Alluviau land is very congenial to pastel, when it is not too moist, particularly where it is taken from a saline bank of the ocean. In Languedoc, earth from the drains and about the houses is preferred, as the most nutritive and substantial manure. Natural meadows, where wheat has grown too vigorously, are excellent for pastel, if they are well ploughed ir and liarrowed. According to the adage of the faraiers of .Thiiringe^ weizenland^ aiich waidland. Meadow land^ is the land for pasteL The number of laborers requisite to cultivate the land^ depends on the nature of the soil^ its pres. ent situation^ and the crops which it has produced the preceding years. The cultivator should be careful to keep the land clear from weeds ; this can be easily done by grubbing, as this method, w^hich tends to destroy the insects, is very benefit cial to pastel. The lumps of earth should be well pulverised, to effect which, the land should be well harrowed, from three to four times, according to the nature of the soih This labor should bere« peated often^ when the meadow on which it is in- tended to sow pastel, has not been broken up for a number of years before. If the land is moist or subject to retain the winter rains, it should be thrown up into ridges^ or trenched to facilitate the. escape of the water. On small pieces of ground^ the land is thrown up with a spade into beds^^ be- tween three and four feet wide, and then well rak- ed. Some farmers first spade the land and then plough it. As pastel requires a strong soil^ it is necessary to increase its fertility by manure, according to its quality. A good soil should be moderately ma- nured ; for the leaves of pastel, which grow rap^ idly, ai e too suculent and do not contain a propor- tional quantity of coloring matter, and, of course, a less productive crop ; therefore, only poor land should be highly manured. It is by this judicious combination that the cuL IB tivator raises tlie greatest quantity of leaves and tlie most coloring iiocculi. Perfectly rotten manure is preferablis to tiiat iu whicli the straw is not entirely decayed. The last does not produce all its eftect during the growth of the pastel^ and when the leaves are gathered^, the straw mixes with them^ and cannot be sepa- rated even by washings which injures the quality of the pastel^ and diminishes its value. In Ger- many the manure is spread on the land in the fall, but it is as well to put it on in the spring, if it is perfectly "decomposed. CHAPTER IIL ^ The Seed^ the time and manner of sowing it. It is said that pastel seed will not keep good more than two years. We have sow n seed which was four years old and it did not come up. If the seed is old^ it is best to soak it in water one night. The quantity w hich ought to be sow^n de- pends on the nature of the soil. Rich land should be sown tliinner than that which is- light and .sterile. If the plants in the first are at too great a dig- tance^ they vegetate too vigorously^ and will be inferior in qnaiity^ as we observed before in iht preceding ciiapter. while on a light soil^ they should be at a greater distance from each other* 19 tliat they may receive more mitrimeiit wbicli is ne- cessary to make tliem grow to their full size. This precept is an exception to the general principles of agriculture. If the plants ^fre too thick^ they should be thin- ned at the time they are hoed. The €juantity of seed which should be sown also depends upon its quality. When it is not too old^, is plump^ heavy and of a dark blue color^ it will certainly come up well. It is not necessary to use so •much seed when it is sown in rows. The seed should be sow n as early in the spring as the season will permit. This period^ for the southern departments of France^ is during the month of February^ com- mencins; a])out the fifteenth : and for the northern departments^ the month of March. As pastel suffers but little from the frosts of spring, it can be sown as soon as the heat begins to produce the least vegetation. If it is sown late^ the leaves are , less and the product not so great. Another reason in favor of early sowing is^ that the insects which attack pastel^ rarely appear early in the spring. Sometimes this operation is delayed for a month from showers and bad weather ; in consequence of which, the- seed is frequently not sown in Langue- doc until the forepart of March. There is a cus- tom in some parts of Germany, of sowing the seed when the earth is covered with snow^, and then \ liarrowing it in, a few days after it has melted. The seed sometimes remains a fortnight on the snow, and from the blue color which stains the snow, the planter can discover whether it has been sown equally or not. Some farmers recommend sowing in the forepart of October^ soon after the ieed is gathered. They assign as a reason, thai the seed comes up better^ that the plants^ so far from being injured by the frosts of winter^ strike roots whicli^ in the springs accelerate vegetation ; besides^ the young sprouts are at this season^ less subject to be injured by insects. We have sown pastel during the three or four first days of August^ which withstood the rigors of wdnter^ and vegetated earlier in the spring. From experience and the situation of the soii^ w e must decide which period is the best. After having sown during the first pleasant days at the commencement of the season^ it frequently happens that the weather becomes cold and unfa- vorable, which prevents germination or the in » sects^ dewstroy the young shoots^ which makes itne» eessary to re-plant ; therefore,, a sufficient quanti» ty of seed should be reserved for that purpose. Some small planters in Languedoc, are in the liabit of sowing, in the same field with pastel) beans, cabbages, or other vegetables. It is unne- cessary to observe that this practice is injurious to the quality and quantity of the pastel, as it pre^ vents that particular attention to its culture which is necessary during its growth, besides' the leaves and rubbish of those various plants, become mixed with the pastel and injure its quality. The most general and expedient method of sowing, is the broad cast, and the seed should be scattered as equally as possible ; therefore, but a small quantity should be thrown at a time. It should then be covered with a light harrow, after which the ground should be rolled to make the surface as smooth as possible. SI la small fields, wliich are laid out in beds, the seeds are sown in drills and raked in, wliich gives a more free and equal circulation to the air, as the distances between the plants are more uniform. The rows should be twelve inches apart, and more w hen a plough is used to till the crop. In Eng- land a machine is used to distribute the seed more equally. This machine is similar to that used to sow^ turnips, (says Dickson, in his Practical Ag- riculture ;) the rows are nine inches apart, and covered with a rake attached to the machine^ or with a light rake in the usual way. The plant comes up in ten or fifteen days ; if it is perceived that the seed has not sprouted, or the sprouts are destroyed by the insects, or by the in- temperature of the season, the land should be im- mediately all sown over again, or the vacant pla- ces, w hen only detached parts of the ground ig without plants ; but if the principal part of the plants have perished, the whole ground should be re-sown. In the first instance, holes can be made with the hoe, and three or four seed thrown in^ and immediately covered over. Sometimes it be- comes necessary to re-plant two or three times. A calm time should be chosen to sow^, for the seed being light, are easily scattered by the wind^ and thus are unequally dispersed over the ground. CHAPTER IV- The necessary labor during the growth of Pastet Pastel should be weeded three or four times^ according to the increase of the Aveeds. The first weeding should be performed when the plants have got two inches high ; that is to say^ aliout a month after planting. The second hoeing should be after the first cutting of the leaves ; the third after the second cuttings and the fourth after the third. The field should be well ploughed and harrowed^ immediately after the crop is taken off^ which destroys the weeds^ which are injurious to pastel. The first and second hoeing tends to facilitate vegetation^ and clear the pastel from weeds^ which are very injurious to it. By this labor are destroy- ed^ not only the weeds^ but the bastard pastel : this kind^ which often grows in fields of pastel, is known by its rough and hairy leaves^ and is pro- duced either from seed of an inferior quality^ or the true pastel sometimes degenerates, and^ at last becomes bastard. When the plants are too near each other, the intermediate ones should be pulled up^ taking care to leave them standing about eleven inches apart. When tiie seed has not come up well, and there are many vacant spots, the first hoeing should be anticipated eight or ten days, when seed should be scattered in the intervals. In the second hoeing, the roots of the bastard pastel which escaped the first, should be dug up. This labor should be performed after the first cut^ 23 ting, unless an active vegetation has given birth to large quantities of weeds ; in this case there should be an intermediate weeding, when the pastel should be thinned out, if the plants are too near. These w eedings can be performed in three way s^ either with a hoe, a rake^ or a cultivator ; the last cannot be used except when the seed is planted in drills. The laborers in some places, use a crooked iron instrument, and work on their knees. In England, the cultivator, or horse-hoe, is commonly used, which can be guided between the rows. Care should be taken not to injure the roots. If seed cannot be procured to replant the vacant spots, part of the plants, where they are too near, can be transplanted in the intervals. Some persons water their pastel from time to time. It is true that such irrigation gives a more luxuriant vegetation to the plants, but the coloring matter produced from them is not so good. It is well to water the plants which have been recently set out, or when they suffer from a drouth. CHAPTER V. Diseases and insects which attack Pastel, Pastel is subject to but few diseases. It is one of the most hardy plants, and well calculated to withstand the intemperature of the seasons. g4j The only disease^ within our knowledge^, Which is injurious to it^ is that which covers the leaves with spots or yellow pustules. There are no means of checking the progress of this disease^ but by gathering the leaves^ which shouhl be done with- out delay ; otherwise a great part of them will be unfit for dyeing. This is done^ notwithstanding they may not have come to maturity. Grasshoppers^ catterpillars^ a species of spider^ snails^ and May bugs^ attack and destroy more or less of the leaves of pastel. As many of these in- sects should be destroyed as possible ; their rava- ges are sometimes so great^ as to render it neces- sary to re-plant the fields. Before we speak of the crop^ and the mode of preparing the leaves of pastel^ we will describe the method of procuring the best seed^ the kinds of crops which may succeed each other in the course of cultivation ; and lastly^ we will consider this plant as an object of fodder for cattle. CHAPTER VL Manner of procuring the Seed, A certain number of plants should be reserved for seed. If there should be among them any roots of bastard pastel^ they should be carefully eradicated^, so that when the seed is gathered, it should be of the first quality. The method which is generally followed^ but which is not the hest^ consists in preserving those plants for seed which have been cut the first year, as many times as pos- sible. These plants shoot anew^ and in the fol- lowing spring and summer, produce the stalk on which the seed grows ; but enfeebled by the pre- ceding cuttings^ their vegetation is not so active^ and as the seed is diminished in quantity and quality, it is best to reserve the necessary plants for seed, without cutting them at all, or, at most^ not more than twice, and then only the most in- ferior leaves should be cut. The seed is ripe in June ; at that time they are externally of a dark blue color, and yellow inside, and begin to fall from the stalk, which is from three and a half to six feet high. The seed is gathered by hand, or the stalks cut with a sickle, and left for a short time upon the ground, until they are sufficiently dry, when the seed is threshed out with a flail, winnowed and preserved like other seed in a dry place. A half an acre will furnish sufficient seed to sow twenty acres. CHAPTER VII. Succession of crops to follow in the culture of Pastel. Pastel exhausts the soil as much as tobacco ; therefore this plant should not be cultivated two 3 28 years in succession on tlie same land, unless it is very fertile, and even then the quality is not so good the second year as the first. There is, not- withstanding, a custom, in some parts of England^ of sowing pastel, two years in succession, on the same land, and sometimes even four years. But this system of cultivation cannot take place but upon very fertile land, which is well manured and kept in good order. The last crop being gathered, the ground should be immediately broken up with the plough and well harrowed. But in case it should be desired to make pastel a fodder for cattle, it is left to grow the remainder of the autumn and the commence- ment of spring; and it will grow even during the winter in warm climates, and then it is pastured by sheep and other cattle when the country does not afford other fresh food. In the first, and also in the second instance, the ground is sowed after it has been well prepared. Wheat is generally the crop which succeeds pastel ; there can be cultivated with advantage on artificial meadows, beans or other vegetables, according to the nature of the soil, the season, or the inclination of the farmer. But the preference should be given to such plants as require the ground to be most clear of weeds. Land on which pastel has been cultivated during the year, should be well cleansed. S7 CHAPTER VIII. Pastel considered as Forage. Some persons recommend pastel as a most ex-^^ celient fodder, and very important, as it resists the frost, vegetates in the Avinter and spring, when the season is mild, and makes good pasturage for cattle, and more particularly for sheep, at a season when the country does not afford any other verdure. It will be found in the 5th voL de la Feiiille dii Cultivateur^ page 5, that M. Bohadsch is the first person who made use of this plant as fodder for cattle. Every body knew the use of this plant for dyeing blue, but they were ignorant that it was a useful and agreeable aliment for cattle.'^ It is said in the third volume of the lavst edition of the Agricultural Dictionary, that Daubenton was the first person who employed it in this way ; but in England, fields of pastel were grazed by sheep a long time before the two periods above mentioned. Th. Hale, in his Complete Body of Husbandry^ vol. iii. page 147? second London edition, 1758^ thus expresses himself on this subject. ^' After the last cutting in autumn, pastel continues to sprout ; it is true the leaves wJiich grow during the winter, are not proper for dyeing, but the pro- duce during this season, is not useless. The field furnishes very abundant pasturage for sheep, both wholesome and nourishing ; and so far from the plant being injured by the sheep, on the contrary, it causes it to sprout with more vigor the ensuing spring,^^ 28 M. Boliadsch pretends from the experimentg tc has made^ that cattle are fonder of pastel^ than trefoil^ or any other plant ; which proves that pastel contains more salt than all the other alimentary vegetables/' He even thinks that the nse of it^ ^' prevents those contagious diseases from which cattle suffer/^ He says^ pastel grows not only in good soil;, but even in that which is stony and sandy. In fact^ he relates several other advantages to be derived from pastel^ which are however^ very much exaggerated. Dickson^ a commendable British author^ says^ it has been given to sheep during the winter ; but it enfeebles them^ and that this method is worth nothing.^^' They are not fond of this plants and jiever eat it, but when pressed by hunger, as has been found by experience. It is customary in Germany to turn flocks into the fields of pastel ; where they eat up the plants that are injurious to it, and never touch the pastel. Cows, hogs and geese, will eat the leaves^ but do not seek them with eagerness « We think it prudent to suspend our judgment upon the advantages which may result from pas- tel as a spring fodder, until proper experiments have been made on an extensive scale, which shall give satisfactory results. But we strongly doubt the success, and warn inexperienced culti- vators to be on their guard, against the exagera« ted statements which the daily papers, and even learned societies often impose on the public. CHAPTER IX Harvest of Pastel. The leaves of pastel should be cut when they have acquired a proper degree of maturity; by a deviation from this rule^ the coloring matter ob- tained will be of an inferior quality. The signs of this maturity are these ; the lower leaves be. gin to droop^ lose their deep color^ and grow pale^ principally upon their edges^ at the period when they have acquired their full length and width ; their blueish green color disappears^ and they ac- quire a certain thickness and consistence^ which is known from experience^ by the touch and sight. At this time it should be harvested without delay^ or a change will take place that decomposes and injures the coloring flocculi^ and which renders the produce considerably less. Besides, the har- vest cannot be deferred without injury to the next crop, which will be retarded in its growth, not have time to ripen, and it cannot fail to diminish the number of crops. The number of crops cannot be the same under all circumstances ; they will vary according to cli- mate, the soil, the state of the weather, the cul- ture, &c. Four, and even five or six crops are made in warm climates, when favored by the fer- tility of the soil and the weather ; whereas^ in cli- mates, and under circumstances less propitious^ only two or three crops are obtained. When the seed is sown the first of September, the first ^3 30 €i*op is cut fifteen days earlier^ and thereby one more is obtained. The first harvest is generally toward the mid^ die of June ; the leaves being then from eight to twelve inches in length. The following crops succeed each other every month^ when vegetation is not retarded by the intemperature of the weath- er. As this plant sprouts with less activity in cold climates^ five or six seeds should be sown between each pla.nt^ as they are cut. The fourth or fifth crop is generally of a very inferior quali- ty ; the fifth and sixths which are sometimes made in Languedoc^ and which are designated under the name of MaraucJiins^ being prohibited by an ordinance. The first crops are generally of a better quality than the last ; thus the first crop is preferable to the second^ the second to the thirds &c. if this rule is general ; but when the spring is rainy and hu- iiiid^ and the rains are abundant at the time of the first harvest^ the pastel which is produced^ is iiifefior to that of the second^ thirds and fourth crops. A warm and moderately moist season^ is favorable to the growth of the last crops. l^'oo much moisture causes tlie plants to grow 'luxuriantly^ but fills them with an aqueous juice^ whicli diminishes the quality of the product A ivariii and rather dry season^ produces the best quality. The last crop is the least valuable, be- cause at that period the rays of the sun are not sofficiently powerful to mature the plants. The intervals which the V€ariations of the weather makes it necessary to observe between the crops^ cause the products to be more or less considerable 31 in quality and quantity. When the rain^ too little heat^ or the cold at the latter part of the season has not permitted the pastel to acquire a sufficient growth, or it is not of a good quality, it is most advantageous to leave it on the ground ; as the plants during the winter and spring grow consid- erably, they can be cut early, and much labour thereby is saved, which can be transferred to the cultivation of other productions : other leaves^ however, will grow up between those of the pre- ceding year, and the pastel which is tims obtain- ed, will not be of so good a quality. The crop should be cut in dry weather, when the heat of the sun is sufficiently powerful to dis- sipate the moisture occasioned by gentle rains^ mist or dew. To perform this operation the la- borers should scatter themselves in the field, raise' the reclining leaves, grasp them with one hand near the ground, and twist them oif. The ordi« nance of 1699, prohibits iron instruments to be used for cutting pastel. We cannot perceive what could have been the reason of this prohibi- tion, and believe that a sharp instrument can be conveniently used with a great saving of time and expense, and without injuring the leaves so much as to twist or pluck them off. A very proper in- strument can be made for this purpose, with a crooked blade, nine inches in length, the greatest width four inches, the least three quarters of an inch. At right angles with the blade is a flat haft three inches long, and from a half to three quarters of an inch broad, to which is attached a wooden handle, forty inches in length. m The common cycle^ although not so convenient as the instrument above described^ may be em- ployed with advantage. The laborers should be careful not to wound the roots^ or cut any weeds with the pastel;, as they would injure the coloring matter; therefore a scythe should never be used. The leaves are thrown into a basket as they are cut^ and conveyed immediately under a shed^ or into some dry or shady place : for they are injur- ed if exposed to the sun for any time^ and still more by rain and moist weather. In Alby the leaves are left to wilt a little before they are sent to the mill^ taking care to turn them from time to time to prevent fermentation. It is thought a more perfect colouring matter is extracted when the leaves lose a part of their aqueous juice by evapo- ration. On the contrary^ it is the custom in Eng- land to convey the pastel to the mill as soon as it is gathered. If it be unavoidable to keep some of the leaves for a long time^, it is best to mix them with those which are recently gathered, and let this melange remain for a time in that state^ be- fore they are ground. In some parts of Germany they wash the dirty leaves by stirring them about In a brook with a pitch-fork^, and then spread them on the meadows to dry ; this practice is sub- ject to several inconveniences. It is difficult to do it on a large scale^ and they run the risk of spoil- ing the whole crop. The small quantity of dirt which sometimes adheres to the leaves^ is not suf- ficient to do much injury to the pastel; besides this method cannot be practised but in very good weather. 33 CHAPTER X. Of the grinding and preparation of PasteL After having taken that care of the crop which has been mentioned^ and the leaves are prepared for grinding, they are carried to the mill as fast as the labourers are able to cut and prepare them for that purpose. The place in which the pastel is prepared should be a shed, surrounded on three sides, and open to the south on the fourth. It should be covered, so that the pastel shall not be exposed to the rain. The land on which it is built should be firm, and inclined a little from the north to the south, and paved with stone or brick. The mill should be in the same place or adjoin- ing it, erected on a circular base of masonry, cov- ered with flag stones, with a wall round the cir- cumference, and an elevation of mason work in the centre, so that the mill-stone can roll in a trough or gutter some inches deep. The stone is placed vertically, and cut in groves on its edge, to prevent its sliding over the leaves, which causes them to be ground sooner and more equally. Through the centre of the stone passes a wooden shaft, fixed to an upright post around which the stone turns. To this upright post is attached a long pole, to which is hitched the animal that turns the stone. This mill resembles those which are employed to make oil, grind apples, break bark, &c. and the latter atiswers the purpose per- fectly well, therefore it is not necessary to give a drawing of the mill; 34 A cerfain quantity of the leaves are thrown into the gutter^ where they are bruised into perfect paste. Some cultivators improperly throw sand under the stone, pretending it is necessary to pre- vent the paste from adhering to its circumference^ but the object is to increase the weight of the pas- tel. This fraud is easily discovered^ and there- fore prejudicial to the interest of those greedy persons who are so injudicious as to practice it. The paste is placed under the shed as it is taken from the mill^ in long heaps which is thrown with a shovel close to the bottom of the wall^ and trodden down with the feet. When the first heap extends the whole length of the wall^ another^ parallel to it is formed^ sloping eacli way^ leaving a passage between the two heaps. These heaps are left to ferment for about eight days^ more or less^ according to the tempera- ture of the weather^ they are then broken up and shovelled into piles^ parallel to the first^ where they are left to ferment^ for fifteen days or tl^ree weeks. Some persons are satisfied to let the pastel undergo only one fermentation. When the wind blows from the south the fermentation is checked, from a belief that it is iniurious and rots the heap. When the heap of pastel is in this state it dries up and cracks open on the surface^ there- fore it should be carefully beat down as often as it is necessary to fill up the crevices : with- out this precaution the pastel will evaporate^ (s^eventerait) as the cultivators term it^ and small worms are produced in the crevices, which are injurious. When the heap is beat down, all that 35 part which is covered with a white mould; or at- tacked by wormS; is thrown off. After the pastel has undergone one or two fer- mentations, it is broken up and pulverized with the hand or mallet with which the hard superficial crust is bruised. The whole being reduced to a powder, and well mixed, is then formed into balls, taking care not to mix the different crops, the one with the other, for in that case a good crop would be in- jured by an indifferent or bad one. These mix- tures should by all means be avoided when one or more crops have been sensibly deteriorated by the effect of the season, or the intemperature of the air. Besides, this cannot be done without leaving the leaves of the first crop too long in a state of fermentation, which is injurious to the colouring matter. It is true that those who culti- vate but a small quantity of pastel are obliged to unite the products of several cuttings, to form a mass sufficiently large to produce a perfect fer- mentation, but in this case the quality is always inferior. To form the pelotes, or cakes of pastel, which are called in Languedoc coes^ or cocagnes^ the matter reduced to the state before mentioned is taken and is successively worked by two or three labourers. The two first press it hard between their hands, and the third gives it the shape by I)ressing it into a wooden mould, and then length- en it by drawing it out by the two ends. Al- though the form which is given to pastel is imma- terial, still the custom of commerce often fixes the shape. It is varied in different countries. When 36 tfeis reason is not decisive for the cultivator^ we advise iiim to choose the form of a common brick. The desiccation and packing will be facilitated more by this than any other method. It will also be more expeditious and economical to form the pastel in iron moulds^ in the manner bricks are made. The cakes or pelotes will thus be ren- dered more equal in size and weight. The an- cient ordinances required that they should weigh twenty-four ounces when they came from the hands of the workmen^ and three quarters of a pound when dry. As the cakes of pastel are formed^ they are put on hurdles and removed into an airy or shady place to dry^ in such a manner as they shall not mouldy which greatly injures them. Some persons expose them occasionally to the sun, and pretend that it improves their quality. They never should be packed up until they are perfectly dry, otherwise they will become heated and deteriorated. In summer it requires fifteen days to dry them, and longer in the autumn. In some countries it is the practice to form long cakes, which are moulded after they are half dried. To make these moulds, take a piece of wood, six inches in length, saw it longitudinally into two equal parts, each of which is excavated; fix the two pieces of wood together with two pins, or in any other way ; when the pastel is to be moulded, a quantity is laid in each hole and pres. sed with a wooden cylinder which is struck with a mallet ; then the two parts of the mould are sep. arated, and the cakes of pastel taken out, which, by this process, are pressed sufficiently hard and solid. 37 The cakes are kept in a loft^ or some place where they are sheltered from the wet. They should be moved from time to time., during the first months to examine them and prevent fermen- tation. When they appear internally of a violet color^ exhale an agreeable odour and are heavy^ you may be assured they are of a good quality. An earthy smell and color are bad signs ; a me- lange of sand^ chaffy weeds^ and other substances, always disclose a bad quality of pastel. This method of preparation^ which has been mentioned^ is that generally employed in Langue- doc^ which^ however^ varies in several respects. In some places they are satisfied with one fermen- tation^ and make the paste into cakes in twenty- four hours after ; in others it is exposed to the air and sun^ for two days ; and if it rains, mats are laid over it ; it is then stirred up and mixed to- gether again ; a month after this operation it is again ground. It is the custom in some places not to check the fermentation before the paste is formed into cakes, which is done as soon as it is taken from under the stones. But it is not a good method as the pastel is not sufficiently mixed and fermented to develope the coloring matter. We shall mention, hereafter, a method practised in England, in the county of Norfolk, which merits a separate article, in consequence of the pecu- liarities by which it is distinguished. Pastel, after having passed through the differ- ent preparations which have been described, is called pastel^ decocagne^^ and is in the state to ♦ Woad-cake. 4i 38 be sold to merchants, who give it the last manipu- lation, an account of which will be given in the following chapter* CHAPTER XL The storage of Pastel. The labor of raising and preparing pastel, which belongs to the cultivator, being finished, there still remains a last manipulation which is called the storage^ and according to established custom, be- longs to the pastel merchant. In describing this process, we shall be principally guided by the in- structions given by the deputies of the states of Languedoc, in 1669. The merchant, after having received the cakes from those who produced them, places them in very dry ware-houses, where there is no risk of their being injured by moisture. These maga- zines are large oblong buildings, the ground un- der them sloping, and paved with stone, with win- dows only on the south side, so that the wind shall not cool the pastel when in fermentation. The walls are constructed of stone or brick, six feet high. The buildings should be so long as to give a space double that which is occupied by the heap of pastel, which is made lengthways, so that it can be stirred up, and moved to any other place. As the goodness of the pastel depends on the 39 quantity put in fermentation, a small mass cannot be operated upon with success. It is necessary to have one hundred thousand cakes at least, each weighing three quarters of a pound. Those who have not this quantity, unite with some others, to make it up, and operate in common. The pastel should be perfectly dry before it is worked over, and as it cannot have an entire de- siccation until some months after it lias been made into cakes, it is not put into the warehouse until the middle of January. This labor should be finished before the end of the month ; for it is be- lieved that the operation will not be so perfect, if undertaken at a period when the weather is more mild. The cold, by concentrating the heat pro- duced by the fermentation, makes it more perfect, and renders the pastel of a better quality. This custom, notwithstanding, is not generally follow"- ed, as many persons begin the fermentation in the month of February and March, even in the south- ern parts of France. The operation is began by crushing the cakes with a mallet, and those which are mouldy, or damaged, are rejected as refuse. The cakes are broken only into two or three pieces, for they ab- sorb too much water if they are reduced to pow- der. The fragments are spread on the ground to the height of six inches, the whole length of the building ; this first bed is sprinkled with a small quantity of water, at different times, then thrown up against the sides of the warehouse ; then a sec- ond bed is formed and watered, like the first, and then thrown upon it. Thus are placed bed upon bed, until the heap is raised about three feet high. 40 Each bed is thrown on without beating or pressing them down; and the whole is then sprinkled with a little water. The heap should slope each way^ and be sufficiently large to produce fermentation^, and preserve the heat. It is left in this state for three days^ at the expiration of which it is moved^ or thrown into a pile^ and after two days watered again. In this last spririkling^ the same quantity of water is used as in the first^ that is to say^ about twelve quarts for every thousand cakes. Some authors recommend putrid water to sprin- kle the pastel with ; or water mixed with urine^ lime water^ &c. It appears these practices are in use in some places ; but river water is best^ and next to it that from a spring. Well water should never be used^ except when the former cannot be obtained^ and then only when it has been exposed for some days to the sun or air. The Maison Eiistique/^ is one of the number of writings in which putrid water is recommended ; and what is yet more absurd^ it is added that the pastel is put into the wetter^ and left to soak for four months J, during which period it is stirred from time to tiwie, &c.^ It is our duty to expose these errors^ that those who consult a work which is too much circulated^ may be upon their guard^ and not be induced to adopt a similar process. It can be known whether the pastel has receiv- ed the necessary quantity of water, by thrusting an iron instrument, called a bigos/^ into the heap in several places. If the bigos enters very easily^ the pastel has been too much watered ; and m * Edit, de 1804, en trois voL in 4to. voL i. p. 614* 41 ihh case it should be left to dry for two or three days ; and if it is pierced with difficulty^ it has not been sufficiently wet ; it is then necessary^ w ithout loss of time^ and before it heats^ to water it as much as may be judged necessary^ and in such a manner as not to be obliged to do it a se- cond time^ for renewing the water cools the heap and ruins it entirely. It is better that it should require water^ tlian that it should be too mucli watered. It is necessary to observe^ that it re« quires more or less water^ according to the hu- midity or dryness of the year in which it has been harvested. The preceding manipulation being finished, the excess of moisture which the pastel contains is dis» sipated by destroying the heap^ and forming others^ by throwing it with a shovel to the oppo« site side of the buildings without pressing it down^ merely smoothing its surface. This labor^ called vante/^ should be renewed every three days during the first month, and once a week during the second^ and every fifteenth day after^ until the heap has lost its heat and moisture^ wliicli is gene- rally about the end of July, when the winter has been rather severe. It sometimes happens the pastel forms a crust upon the ground near the wall where it was heaped up ; as this crust rots and injures by admixture, the pastel of a good quality, it should be carefully rejected. After it has lost its heat, it is left in a heap for two months, without being moved, that it may re- ceive all the benefit it^s susceptible of. It is still better not to use it until the close of the year, and even at the end of eight or ten yearS; taking care m to move it every three months^ to prevent it from heating. The preceding manipulations vary in different countries. Carluc says^ after waterings it should be moved;, and then moistened every day for twelve days. Moving it often and v^ater- ing it frequently, checks the fermentation, and prevents it from heating too much. It is the custom in Germany to water the heap of pastel with hot water, when the fermentation is checked or retarded by the winter frosts. This practice can be imitated with advantage in like circumstances. But it is more sure and simple to ameliorate the temperature of the air by means of a stove. In some places they mix a heap in full fermentation with one where the fermentation has not been so rapid. This mixture has its ad- vaiitag'^.s. Pastel, after having passed the last process of fermentation, is called powdered jidstel^ and is fit to be used in dyeing. It is packed in frails, sacks, and casks. The products of each crop should by all means be divided when it is pack- ed, to preserve each quality separate, so as not to injure the good by mixing with it the bad, or that of an inferior quality. 43 CHAPTEH XIL The Culture and Preparatio7i of Pastel in England. We have thought it would be interesting to give, in a particular chapter^ the culture and pre- paration of pastel, as practised in the county of Lincoln, in England, according to the newest ex^ periments made by Mr. CartwrigW, on a great scale, with as much intelligence as success. The result of this experiment is a proof of the great benefit which agriculturalists will receive from the culture, when attempted by capitalists, and under propitious circumstances. This ingenious and interesting method which we shall describe^ is extracted from the report of the Committee of Agriculture, for the county of Lincoln, published by the London Board of Agriculture.^ Pastel has been cultivated for a long time in this part of England. Land which has not been ploughed for a number of years, is chosen and cultivated with pastel, for two or three, and even four years successively, according to the elevation and fertility of tlie soil, &c. The fields are broken up the beginning of February, unless the ground is too wet, when the labour is deferred until the end of the month. Care is taken to plough it five inches deep, with a three horse plough, which is followed by a man with a spade to throw over ^ General View of the Agriculture of the County of Lin- coln, &c. London, 1799. the sods wliicli may not be turned siiMciently with the ploegh : this is done to prevent the grass from sprouting up among the pastel seed. A. strip is then harrowed at different times sufficiently wide to admit the sower^ which is then rolled ; and thus are sowed^ successively, different portions of the field, from the middle of March to the middle of May, so that the crops may not all be fit to gather at the same time. The sower scatters the seed in the furrows, from eight to nine inches apart. When the earth is not sufficiently pul- verized, it is sowed broad cast, and rolled over twice, if necessary, to make it perfectly smooth. The English sow two bushels of seed to tlie acre. Old fields are harrowed from twelve to fifteen times, when the roots are abundant; the ground is even dug over with a spade when the roots are very strong and tenacious. This spading is very useful as it destroys the worms and other insects which generally are very numerous in this kind of land. These divers labors are finished by making trenches, to let the rain which falls run off, for if it remains, the crops of pastel are destroyed. When the plants begin to sprout they should be examined, to see whether they are injured by the turnip fly, or frost. These two scourges sometimes entirely destroy the plants, so that it becomes necessary to sow the field again. It is not uncommon to be obliged to replant two or three times. The field is weeded during the month of May, and executed with care by the men, women and children, who, kneeling dow^n, dig up the weeds with a small instrument, with 45 one hand^ and pull them up with the other. This labor, as well as that of gathering the crop, is done at a fixed price per acre. The field is weed- ed twice before the first cutting, and a third time immediately after. The first crop is made on low land, during the fore part of July, which is three weeks before that on land more elevated and cold, the second is six weeks after. The weeding be- gins the same day the crop is gathered, and both kinds of labor is performed by the same persons ; the leaves of pastel are raised up and twisted off with the hand. They are eight or nine inches in length, when the land is good, and the season fa- vorable, and shorter under different circumstances* Sixty or seventy dozen of baskets are distributed in the field, into which the laborers throw the pas- tel, as it is gathered. An osiery is pianted, which furnishes a large quantity of willow for making the baskets. The ancient custom was to put the leaves of pastel into large waggons, and carry them to the mill. Mr. Cartwright, not finding this method sufficiently expeditious, and as it could not be executed with neatness, substituted a horse cart, as much preferable. The cart body is taken from the axletree, and raised by pullies to the upper story of the mill. This mill grinds four or five times as many leaves as the old kind. It has eight wheels, made of bars of iron, which by the unequal surfaces they present, bruise the leaves much better. They are seven feet in diam- eter on one side, and six feet the other, and three feet thick ; they are moved by twenty-four horses^ which are relieved by others from time to time. 46 After the cart body has been raised by pullies to the first story^ on the frame on which it was placed^ it is rolled into the miil^ and when it reaches the place destined to receive the leaves^ the moveable planks are taken up, and the load thrown down under the frame ; the leaves being thus deposited, are piled up in heaps, from whence they are thrown with pitchforks, into circular troughs, from which they fall under the mill ; this operation is thus executed with great celerity. A very simple and ingenious method is employed to collect and retain the pastel directly under the wheels ; this effect is produced with two planks, which follow the circular movement of the wheel, one being fixed on its interior, and the other on its exterior side. The functions of these two planks are changed, as soon as the matter is suf- ficiently bruised, and instead of collecting it upon the circumference described by the wheel, they throw it off from the wheel, and it is received out- side of this circumference, upon a compact pave- ment. It is to be observed, that the ground upon which the wheel rolls, is covered with granite, to resist the friction produced by the bars of iron, of which the wheel is formed. More leaves are thrown down under the mill, when this paste has been removed, which is thrown with shovels into two chambers on the side of the mill, through four windows, made for that purpose. This mass is left for a short time, to allow the juice to run off; and when it is of a proper consistence to be made into pelotes, the workmen provided with the necessary instruments, commence their labor. The pelotes are put into a dray, and carried to the 47 place to dry them. They are immediately placed on hurdles^ made of parallel sticks^ which slide in the groves of a frame. The drying places are covered^ and have several ranges of hurdles^ through the middle of which rows is a gallery^ three feet wide^ which admits the laborers to pass, and gives a fine circulation of air. After remain- ing a fortnight to dry, the pelotes are stored in chambers over the place where the leaves were ground. Here they remain until the crop is en- tirely gathered, and the workmen can give them the last manipulation. The drying places have double galleries, which make four ranges of hur- dles ; those which have eight galleries, contain each 384 hurdles, in all 307S. A place is reserv- ed in the lower part to contain the empty casks in which the pastel is packed. Thus is executed daily the various work, dur- ing the whole time the crop is gathering. Two cuttings annually are always made, and even three, when the season is favorable. The first and second, produce pastel of the first quali- ty ; but the third is inferior. Nothing is done to the earth after the crops are gathered, except making some trenches to let the water run off, during the winter. The ground is ploughed in the spring, as early as possible, and sowed about the second week in March, in the same manner as the year before. A part of the field is reserved for seed. Some cultivators, how- ever, take off one crop, but as the seed is of an in- ferior quality, Mr. Cartwright does not follow this practice. When the sowing has been delay- ed, and the roots of pastel are too far from each 48 otherj, tlie vacant places are filled iip^ by making trenches^ with a triangular hoe^ in wiiicii the chil- dren scatter seeds^ and this operation is perform- ed even as late as June. Pastel is cultivated in the same field for two^ three^ and four years. Mr. Cartwright proposes to observe the following course of crops. 1. Pastel. 2. Pastel. 3. Pastel^ and upon very excellent land^ pas- tel the fourth year« 4'. Oats. 5. Oats. 6. Cabbages. 7« Oats. 8. Grass^ and should thus remain seven or eight years^ and be reserved as a pasture for sheep and a few cattle. Mr. Cartwright is of opinion that this culture improves the land so much^ and leaves it in such a good state for commencing the cultiva» tion of pastel upon^ that the owner is well com« pensated^ although the crops obtained are not val- uable. The buildings which have been described are calculated for the several crops of two hundred acres of pastel. Thus^ suppose tliis plant^ is cultivated but three years in succession in the same iield^ nine hundred and eighty acres give by this system an annual crop from two hundred and nine- ty acres ; but on an estate of eleven hundred acres^ it is easy for the owner to lengthen the time^ the ground shall remain in grass^ if judged expedient. It now remains to speak of the last labour be- stowed upon pastel during the winter to render it fit for dyeing. It is sufficient to ferment for seven 49 eight weel^s; this is calied in England couch- ing, and in France agrenage. The pelotes when dry are reduced to powder^ under the mill^ in the same manner the leaves were ground. They are placed in the same story in which the leaves were first stored^ and from this magazine, situated above the mill, they are thrown down^, where they are to be ground^ and when they are reduced to powder^ it is thrown into the two adjoining chambers^ as was the paste. This powder is heaped up from two to three feet high, sprinkled w ith water^, and turned over with a shovel. This labor is daily repeated^ adding more or less water^ to excite the necessary fermentation. This ope- ration should be performed by an intelligent and experienced man. The principal laborers should have had sufficient experience to regulate the heat of fermentation^ and, cause it to subside equally through the whole mass. A certain address is necessary in the management of the shovel^ in turning the pastel^ that the parts which have a disposition to adhere may be divided. It is ne- cessary to divide the pastel with the hand^ when the pelotes have not been well formed^ dried^ and preserved. All this is necessary^ to obtain a dye- ing material of the first quality. The pastel should cool gradually^ when the fermentation has subsided, then it can be preserved in a place prepared for the purpose, packed in casks, and be ready for sale to the dyers. 5 PART SECOND, HISTORY OP PASTEL, ANALYSIS AND EX- TRACTION OF THE FLOCCULL CHAPTER L HISTORY OF PASTEL. Pastel is one of the most useful plants in the arts^ and most anciently employed, not only by civilized people, but even by barbarous nations. The period of its history certainly goes back beyond the existence of Greece, and extends to the present time. Its use in dyeing, which has not been supplied by any other substance, not even by indigo, assigns it a distinguished rank among the numerous economical plants, from which mankind hav^ learned to derive great advantages. We find it mentioned in several Grecian and Latin authors » Isatis,^^ says Galenus, " is a. cultivated herb which the dyers use to color their wool.^ * Galenus lib. 6 de Fac. simp. med. p. 1 79, 51 Dioscorides expresses himself in the same man- ner^ when speaking of this plant.^ Csesar^ in his Commentaries^t and Pomponius Mela, in his Geography,! reports that the people of Great Britain colored their bodies bine, with pastel ; and Pliny^ informs us, that the women appeared at certain sacrifices, after having colored every part of their bodies blue with the same plant. The same author speaks of the Isatis as employed in his time by the dyers to color their wool.|| Ovid alluded to the preceding usage in these two lines. ^ " Fcemiiia canitiem Germanis inficit herbiSj " Et meiior vero guoeritur arte coior." We find among the modern Gauls a whimsical taste to disfigure themselves, which characterized their ancestors, with this difference, that those of the present age know how to modify the variety of colors. Every thing is improved by the prog- ress of the arts. A passage of Vitruvius seems to prove that at the epoch in which this able ar- chitect lived, the method of extracting the flocculi from pastel was known. " Indigo (says he) being very rare, it was imitated by a melange of pastel and saline earths. The pastel of Louragais has been celebrated for many ages, although several German authors give the preference to that of Thuringe. It wm Dioscor. lib. 2, cap. 180. t Ca38ar lib. 5 de Bello gallico. :|: Pomp. Meia de Sita orbis, b. 3, c. 6. § Pilnius Hist. nat. b. 22, c. 1. ij Pimius F^ist. nat. b. 20, c. 7, | 25. •5[ Vitr.b. 7, c. 14. formerly cultivated in several cantons of France^ particularly in the diocesses of 1*oulouse^ Alby, Lavaur^ Saint Papoul, Bas Montauban^ and Mi- repoix. It is pretty extensively cultivated in Kor- Biandie^ The author of Commerce de VAmerique par Marseille^ says^ that Britany formerly produced a great quantity. It is now ^^ultivated in some parts of France. But the process of manipulation is very defective^ and the products cannot be used but for the common colors. Olivier de Serres^ says^ that in his time^ pastel of a good quality^ was not produced in France^ except in Lauragais. He thus expresses himself upon this subject. " In all this kingdom it does not grow well but in Lauragais, as the reiterated experiments of several good cultivators have proved. Those who have endeavored to raise it in different places, with the requisite care and ob- servation, as to the soil, the culture and manage- ment of the plant, have found the pastel, on trials so feeble and small, as to be of little value^ and scarcely worth any thing for dyeing.^^ Olivier does not affirm this as a fact, but only says he was induced to believe it from some experiments wMcJi were made. We doubt the correctness of Ms statements, and even dare affirm, that there can be obtained in a great number of the southern departments of France, pastel of as good a quail- ty as that of Lauragais, if it is raised with care and requisite observation as to the soil^ the culture and management of the jilant. Prejudices have existed, and still exist, which induce cultivators to believe, that such or such productions canoot be raised to advantage^ but in particular places. The erroneous opinious Avliich existed on Meri- nos^ and v/hich were dissipated some years since^ is a strildng proof of what we have advanced. It remains for agricultural science^ supported upon the principles of sound philosphy^ to destroy an- cient popular prejudices^ which are always injuri- ous to the progress and development of the most useful arts. Thuringe formerly produced a great quantity of pastel^ very celebrated throughout the north ; this culture has considerably diminished, even in France, since the introduction of indigo. In Haute Thuringe, and the environs of Erfort, the greatest attention is paid to this plant. A German author pretends, that the cultivation of this plant was carried from that country into France. This hazardous opinion is not supported upon any au- thority. It is much more probable that it came from the east into Italy, passed from thence into the south of France, and was afterward spread over the rest of Europe. Several cantons of Italy are enriched by the cultivation of pastel ; among others, the territory of Rieti, in Umbrie, where it is raised in great perfection. It is attended to in some parts of Ca- labria, Lombardy, Home, Marche d^ Ancone, and particularly, in the environs of Nocera, where Mathiole reports, there is a small borough, called Guado^ from the extensive culture of pastel. This plant was introduced, a long time since, into seve- ral parts of Piedmont, particularly at Quiers^ w^here there are, even at this time, extensive fields. Lincolnshire is the part of England where pas- ^5 5% tel lias been most extensively cultivatecL We iiave given an account of a considerable experi- ment wliicli was made in that coimtj^ There are some small fields in tlie neighborliood of Bristol^ and it is found in several parts of NortliamptoOo It appears tbat this plant has been cultivated in England but tv^^o hundred and fifty years^ as will be shown hereafter. It is an object of cultivation in the island of Corfu^ and other places of the East ; also in Penn- sylvania^ and some other of the western states of North America* It grows natorally^ and is cul- tivated in several places in Bpain^ according to %ier.^* This culture must be very circumscribed^ if it yet exists in any place^ for we have not found it in a single province^ notwithstanding our re- search upon the agricultural products of that countr)^ ' Pa,stel was^ however^ known^ cultivated, pre« pared and used in dyeing in that country before the twelfth century. Eben el Awam^ an Arabian au- thor^ who lived in the twelfth century, gave a very r^ircumstantial detailed treatise upon paste!^ and quoted upon this subject another author^ Abu el Jair^ who had written upon agriculture before him. Both of them cultivated fields of pastel in the environs of Seville, The Spanish translator uses the word hortense/^ to render the Arabic expression, which designated pasteL But the text is so clear that it cannot be mistaken. The following is an extract from chapter vii. vol, S. p. i23^ in which Eben el Awam speaks of this Floro Espaiiola, v. 0, p. 28L 56 plaiit.f ^* Pastel prospers in cold climates^ and three crops are made of the leaves^ of which the first is preferable to the second;, and this to the third. It is sown in places not dependent on ir- rigation^ from the fifteenth of February to the first of March. The leaves are gathered when they have come to maturity. They are ground, then left to putrify in paniers, care being taken to water them fre€|uently. They are left in this situation for four days, then stirred with a shovel, and watered again, until a putrid odour is emitted. This is then trodden down with the feet, into a tenacious mass, from which balls are formed^^ which are dried in the sun, and then are fit for the dyer.'^ The Saracens, known more recently by the name of Moors, much superior at the epoch we have mentioned, to the^hristians, by their know^» ledge of the sciences and arts, introduced the cul- tivation of a great number of plants, not only into Spain, but into some parts of Africa and Malta. It appears that indigo was cultivated in this island at the time they governed it, and it isliot improb* able that they brought pastel into Spain. W e have not found any indication in the wri(» ings of travellers upon the cultivation of pastel in the East Indies. We do not know whether this plant is known and used in those regions. Some kinds of pastel, and probably Isatis tinctoniap grows naturally in Syria and Egypt. This plant is also found in the West Indies ; but as the cultivation of indigo, in warm climates^ T Libre de Agricultura. Madrid, 1802, 2 v, in fol. 56 offers greater advantages than pastel^ liie latter has been neglected. It appears^ nevertheless^ that the Chinese^ v^hose active industry renders every thing profitable^ have known how to render this useful. Duhalde is the only writer known to us^ w^io mentions this. " When the Chinese v> ish to colour white damask blacky (says he^ vol. iii. p. 498. Description de la Chine^) they dip a piece twenty times or more in a cauldron^ or bath of ^ tien^^ that is to say jiastel^ and let it dry after every dippings &c.^^ He also speaks in these terms^ vol. i. p. 27. " The plant ' tien/ or ^ tien lioa/ is very common in the provinces, and is much used.'^ ^' When it is macerated in water^ and prepared in large tubs, it gives a blue colour W' hich answers for dyeing.^^ " That of ' Fokien- gives a very fine colour, and is much esteemed for a kind of painting which they call ^tan-meiJ Some persons have presumed, fnym the macera- tion to which the Chinese submit this plant, that Pohalde was deceived ; and that he took indigo for pastel. But he speaks elsewhere of indigo : and he appears too enlightened to fall into this error. It is more likely that the Chinese, in the prepara- tion of pastel, made use of the process which is now practised to extract the flocculi from indigo ; the application of which has been recommended by several able men for fifty years past, and which has gained some success. It is probable the Chi- nese modify the operation by some preparations and ingredients, which are unknown to us, and which renders the execution more easy and ad- vantageous. We indulge these reflections to ex- pose to view whatever may tend to be useful in dyeing. 67 The most distant epoch of modern times, whick has offered us any certain information upon the coloring use, and commerce ©f pastel in France^ does not extend beyond the year i : it is, how- ever, doubtful whether its culture and use was not known much more anciently in France. It ap- pears that St. Denis, near Paris, was, toward the middle of the thirteenth century, a commercial entrepot for this plant. St. Denis has even in our days a place called " Marche de GuedesJ^ It has been attempted to carry the culture of pastel in France to a very remote period, by quoting a passage supposed to be from Theophrastes, in w^hich it is said that the FectosageSy or inhabi- tants of LGiiragais cultivated^ prepared^ and used pastel for colourings as in our time,^^ But this passage does not exist in the work of the Greek naturalist. It was written by his commentators, who reported what was practised at the period in w^iich they lived, that is to say, towards the mid* die of the seventeenth century, from which it ap« pears there is a difference of sixteen centuries at least. Pastel is mentioned in these terms in an ordi- nance of Charles-le-Bel, of the 13th of December, in the year 1324, article 7 • for every twenty sous ivorth of pastel J there shall he paid four denierSj and below twenty sous nothing.^^^ This ordinance relates to merchandize exported out of the kingdom. Another ordinance of John I. or John 11. dated in the year 1350, proves that pastel was a common object of cultivation m Voyez Secousse, Ordonnances ties Reis, vol. ii. p, 147, 58 France. It is said^ title xx, no labourers can work with the hoe^ or spade ^ but in vineyards^ ex- cept upon land where horses cannot be iised^ and also pastel land."^ To this ordinance^ which con- tains an absurd prohibition, another can be added of 1358, which prohibits the exportation of pastel, article 7 ^ colours for dyeing clothes are pro-- hibited from being carried out of the kingdom^ while that of 1356 permitted it. Omnes abitato- res dicti loci Avinionetif possint sine licentia eujus libet^ usque ad tres annos^ a regno nostro extrehere pastelliim cretum in terris propriis eorumdem with a restriction that this shall not be done by the enemies of the state. Proviso tamen quod dictm mercaturm ad nostros vel regis nostri inimicos nullatenus ferantur vel portentur. Two ordinances of Charles V. the one of 1358, and the other of 1397^ make mention of pastel ; this last proves that the culture and commerce of this plant in Picardie was considerable. Thus it is expressed. Charles^ 8^c. we establish at the port andharborofour city of CrotoyX an entrepot of pastel in pipes and tons, which shall be carried by the river Somme, and thence by sea out of our said district of Picardie. The commencement of the fifteenth century of- fers some historical monuments relative to the subject on which we treat. There exist letters of Henry VI. of the year 1434, by whicii is con- firmed tiie regulations made by the exchequer of Voyez Secoiisse, OrdonriaDCfS des Reis, vol. ii. p. 358, t Avignonet est uiie petite vilie du departoieot de la Haute, Garonne. I Now a little village at the mouth of the Somme. 59 Eouen^ found in the following passage : no tchite cloths can be colored with woad^ if after dyeings they are not of a good and royal color. What we learn from this is^ that woad^ or pastel^ was only used for the best colors. We find in the history of Languedoc^ vol. 5, page 30^ a passage in which it is said^ that there was laid, in 1463^ an impost upon pastel^ when it came from the mill ; also^ that upon the expor- tation out of the country^ this merchandise should be transported to Bordeaux, and that from this city it be disposed of to strangers. This com- merce was carried on with the same activity in 1537? during which year the deputies of the states of Languedoc obtained from the king, the revoca- tion of some duties which had been imposed upon pastel^ payable at Bordeaux.^ Several passages in the " Art of colorings by Hosetti^^^ which we have elsewhere cited, and which was published in 1540^ proves, Ist^ that pastel at that time was cultivated and prepared in the Roman states ; 2d, that it was employed in dyeing without indigo. It is said at the 4th page, ^' that pastel is a plant which grows in Itome^^^ which they call gualda, that it is suffered to fer- ment like a dung heap, and is then used in dye- ing green, blue and black colors. Tubs of pastel and indigo were not compounded at this epoch, at least there is no mention of it in any part of the work which we quote. The author uses only the expression of " calderade la for de enego^^ and * History of Languedoc, by a Benedictine, in foL voL v. p. 126. 60 movQ commoBly lie says that it is rjecessary to color neljior di endego^ an con endego jino.^^ He speaks only of tubs^ in wMch were put 500 pounds of pastel^ and agreeably^ the ordinances^ " Figlu ano lira 500 di guado e conzano una Una come posta V or dine But be does not say that indigo was added. It is probable that the application of it to dyeing coming from India^ it was employ- ed^ at the commencement of its introduction into Europe^ among the processes in use in those re- gions^ and that insensibly it was mixed in the tubs of pastel. The commerce of this last plant had lost noth- ieg of its activity in France^ toward the year i55% ; it also appears by the letters patent of Henry 11^ cited by M. Puymaurin^* by which the king "per- mits the merchants of Toulouse to convey into Flanders^ Portugal^ Spain and England^ their pastel which they have been accustomed to sellP This commerce continued up to the time when in- digo began to become common in Europe. This production of India was not introduced among the dyers in France, even in 1577? ^t wbich epoch it was used and even prohibited in Germany, by the Emperor Rodolphus II. The first fact is to be inferred from the contents of the decree of the par- liament of Paris, dated September 7? 1577* Article 17- " The dyers of good colors shall make use of the following ingredients^ and no others Among the enumerated drugs which follow^ there is no mention of indigo as permitted or prohibited. We flnd^ among other things, "Pastel which * Notice upon pastel, 1810, in 8vo. 63 pages. 61 comes from Totdoiise and Mhy^ and pastel which grows in Frovence and Germany.^^ This last passage proves that tlie culture of pastel was ex- tended into Provence^ and that it was imported into France from Germany for consumption. It also appears clear that the German pastel had the same coloring qualities as that of France^, as it is permitted by the regulations for dyers of good colors to make use of it. This is likewise in sup- port of the opinion we have before advanced^ to wit, that a great part of our departments are capa- ble of producing pastel^ equal in quality to that of Languedoc. Catel^ in his Memoirs of the History of Lan- giiedoc/^ 1633^ pretends '' that there is no other province in Gaul which produces pastel^ butLan- giiedoc.^^ He was in an error upon this point ; but he has informed us of the extensive commerce in this article in that province^ before the period in which he wrote. " The cultivation of pastel/^ lie observes^ " has heretofore been so useful and profitable to the country^ that all the rich mer- chants have made themselves so by this trade.'^ W3 read in the book called the " Merchand^^^ that formerly there was transported from Toulouse to Bordeaux^ by the river Garonne^ every year^ one hundred thousand bales of pastel^ worth at least fifteen livres per bale^ which amounts to one million five hundred thousand livres^ from which proceeded the abundance of money in this coun- try : but wars have depopulated the country, and the introduction of indigo has entirely ruined the trade of pastel. 6 6S The Generallnstructionsfor Dyers of Wool/^ Paris, 1661, page 83, increases the losses to a xnoch more considerable sum. The failure of the sales of pastel has produced a loss of more than foiir millions of livres to Haut Languedoc, since the commencement of this century, notwith- standing the edicts, the decrees, and ordinances of the king, the parliament, and states of Langue- doc, in favor of it, and to prevent the use of indi- go all over France/^ The use of it was not known in i57% when E. Etienne and J. Liebault printed their " Maison Mustique/^ and Languedoc enjoyed the benefits which the culture of pastel produced. The Toulouseans whose country produced large quantities of pastel^ threw the pelotes into vats^ in which was put wool^ to be dyed of a blue color^ or blacky or other colors^ according to the pleasure of the dyersJ^^ The last is rendered more certain by the testimony of L. Fioraventi, w ho, in his Miroir universel des ^irts et Sci- ences/^ Liv. i. chap. 51, de VArt du Teinturier et de rescouleurs^'\ is silent upon the use of indi^ go, and mentions pastel several times ; thus, in chapter xv. entitled the " Art of Painting/^ he notices indigo as a color used in painting, and calls it " endique/^ and endic.^^ ' " Indigo with white lead^ made Turkish blue/^ page 81. The work of Olivier de Serres, dissipates all doubts which can arise on this subject. " Katurally, without aid (says he) pastel makes a blue color * L' Agriculture et Maisou Rustique, 1574, p. 132« t Seconde edition, de 1586, trad, par G, Chappays, €3 for woollen cloths^ and by a mixture with other drugs^ blacky dun^ violet^ brown^ green^ and in a word^ it is employed in all dark colors. Of itself^ alone^ it dyes a clear blue color^, more or less ce- rulean.^ The same author adds^ a few lines lower down^ " that pastel^ when dissolved^ throws up a blue froth, which, if inadvertently or care- lessly left in the vats, spots and stains the cloth ; the dyers fearing this, carefully collect it ; it is then dried and converted into a powder, which they c^llfloree^ and is used to color certain silks. Painters also use floree as a violet color, and call it inde.'^ This substance must not be confound- ed with the true indigo, although it bears the same name. In a work wherein we treat of the history of indigo, we observe it was called by the Ital- ian authors, indico. We do not adopt the senti- ments of the commentators upon the last edition of Olivier de Serres, in w hich they say, page 521^ vol. 2, that Olivier confounded the tise of pastel ivith that of indigo. It is to be presumed that indigo began to be in- troduced into France, for coloring wool, towards the end of the sixteenth century. The author of Commerce de PAmerique par Marselle, vol. i, page 371^ quotes a declaration of the 27th of Au- gust, 1598, by which dyers are prohibited from using indigo. M. Puymorin speaks of a decree of Henry IV. in 1609, in which the king prohib- its on pain of death^ the use of a false and perni- cious drugy called inde^ (indigo.) This decree * Le Theatre d'A,2;riculture5 et mesnage des Champs Pa- fis, IGOO, in fol. p. 735, 64 is not found printed in any collection. The me of indigo in dyeings was permitted in France^ in 4634^ as appears from a work entitled " Memoire pour te retablissement des Manufactures de draps en France.^^ The same fact is confirmed by the 5th article of the Statute et ordonnance pour les teintiiriers de bon teintde draps^ &c. of the month of August^ 1757'» where it is said^ that for dyeing blacky or royal blue^ the cloths shall be colored with pastel and indigo. In the General In- structions for Dyeing Wool/^ &c. of 1688^ it is permitted to use six pounds of indigo for each bale of jjasteL We will remark that Hellot is de- ceived^ when he says in his " Art of coloring wool/^ page 188^ that the prohibition of Colbert^ against using indigo^ had not been taken off until 1727. The preceding quotation proves the con- trary. This coloring substance was occasionally intro- duced^ because it was cheap, not costing more than from two to three livers per pound, the ease with which it was used, the abundance of its coL oring matter, and the scarcity and bad quality of the pastel, and finally, custom had rendered it in- dispensable, so that the dyers, who had not been enlightened, until modern tim.es, by the flambeau of chemistry, thought that it could not be replaced by any other material. But let us continue the history of pastel down to the present time. This plant has been cultivated for several cen-. turies in Crermany, aod was employed in dyeings as far back at least as the tenth century, according to Beckmann. This cultivation was confined generally to the environs of Erfurt, in the third 65 centiiiy; and formed the principal occupation of the inhabitants;, which is to be learned from an ancient chronicle^ in which it is stated that the in- habitants of F^rfurt^ after having destroyed the fortresses of the brigands^ in the neighborhood of Maubschloesser^ sowed pastel^ to make known the exploits in which they had signalized themselves. It is to be seen by the following passage^ extracts ed from the regulations published upon this sub- ject in 161S^ by the magistrates of Erfurt^ that this commerce was^ before that time^ very exten- sive. Considering that pastel is^ and that it for- merly has been^ the principal riches of the city and environs of the country^^^ &c* This fact is attest- ed by an ancient record of the city of Erfurt, hi which it is stated^ there is cultivated in Thiirin- gia such a large quantity of pastel^ that the bene- fits which result therefrom^ cannot be compared* but to a mountain of gold/^ The most ancient statutes of the city of Erfurt^ dated in the year 1306^ contain a regulation relative to the sale of pastel^ and mention a market called " Waidan- ger^'^^ (place of pastel.) This kind of industry^ which had accumulated riches in the city of Erfurt^ was disturbed in 1509^ on account of the civil dissentions which divided the citizens^ and during which several magistrates were imprisoned^ and the burgomaster^, Heller, conducted to the gallows. Several per« sons, distinguished by their rank and wealth, left Erfurt and retired to Gotha, Weimar, and other neighboring villages. The political troubles hav- ing kept them from their country eight years, and some never returning, they spread this kind of *6 66 cultivation into several parts^ to tlie injury of Er» furt. The injury tliis country received was still great-^ er toward the middle of the sixteenth century, at which period^ the use of indigo began to extend into Crermany. The emperor Rodolphus II. pub- lished in 1577^ a regulation against this new intro-^ duction^ in which the epithets prejudicial;, cheat* ingj corrosive^ devouring and diabolical^ were be- stowed on indigo, and proliibited it to be used^ by all dyers^ under the penalty of the confiscation of their property and dishonor. This prohibition was renewed in 159% and 1603, according to Beckman, and again in 1670, according to the be- fore mentioned memoir. Tlie Saxons imitated tliis example, and pronounced anathemas against indigo, in 1650, and prohibited its use under cor- poreal penalties, believing that they should pre^ serve, by such means, the advantages w hich they desired from the culture of pastel, since the disas- ters of Erfort. But the use of indigo daily in- creased in the empire, notwithstanding all the laws, all the sermons, and all the efforts to pre- vent it. The elector of Saxony wished, in 1652, to re- new the divers regulations agaiust indigo ; and to this effect, directed the different dyers, who assem» bled at the fair of Leipsic, to examine them ; they presented a report in favor of this coloring matter. They stated, 1st, That having been ruined by the war of thirty years, and that of seven years, it was not possible for them to make a good color with pastel^ ?vt less than from 120 to S40 francs ; " whereas^ by tfj^ing indigo, it would not, at the ex- \ 67 feiit^ exceed four franks. This proves tlie great disproportioa between the ancient and modern prices of these two substances. 2d, That most of the ancient dyers being dead^^ those who practiced dyeing at the present time^ did not possess the knowledge, or the necessary experience to dye with pastel, as they had for a long time, used nothing but indigo. This fact be- ing alleged by the dyers, convinces us that the an- . cient process differed from the modern, and if a good color is not now produced with pastel alone^ it is because the method of using it is lost, and we are ignorant of the process. The elector would not have absolutely interdicted the use of indigo^ if it had been impossible to have produced equally as good a blue color with pastel alone, which sev- eral persons pretended was the case, and that the colors upon wool, before the use of indigo, were not as perfect or as brilliant as those produced at this time. Those who wished to use indigo, did not fail to allege this reason in their favor, as is easy to be perceived in examining their opinions on the subject. 3d. That the vats of pastel are subject to change, [die waidfarbe iimschlueg^) and ultimate- ly become unfit for use^ which never happens with indigo. 4th. That it was impossible to procure old pas- tel, and of a good quality. 5th. That the cultivators mixed other plants with it ; that it was badly prepared, and that the cloths were often so imperfectly colored with pas- tel, that the dyers were obliged to indemnify those w ho delivered the cloths to them to be colored. 68 6tlie That tlie color was sooner produced hj indigo than pastel^ and it became necessary for the merchants to wait a long time^ when tiie latter was iised^ and that the situation in which thej were placed^ put it out of their power to suffer inucli delay, 7th. That since the introduction of indigo^ the price of dyeing had fallen one half;, and that pas- tel could not be used without raising it^ which augmentation the merchants could not afford. 8th, That the price of potashes being very high^ they were obliged to substitute lime in using pas- tel, which was not the case with indigo ; and that this last colouring substance burnt the cloths less than pastel prepared with lime. 9th. That the consumption of pastel being con- siderably diminished for a long time^ and those who formerly understood the mode of preparing it properly^ being dead^ without leaving any pupils, they cannot find at the present time any person to execute this labour. This representation of the German dyers proves that the perfect preparation of pastel is not very easy, and that the first quality cannot be obtained but with great care ; it is for this reason that at- tempts to color with pastel alone should never be made but when it is made of the best quality. We see by what has been said, that the causes which ruined the culture and commerce of pastel in Germany, and introduced indigo, were very nearly the same in France. The merchants, and particularly the Dutch, aided in the sale and use of this exotic substance, and Thuringe thus lost a very important trade, Ghrolachius says that it 69 had ramifications in almost every part of tlie world : et totum ferme orbem terrasiim extendu tur.^ Tliree hundred villages in that country were entirely supported by the culture of pastel in the year 1616. Several made an annual profit of from 480,000 to 640,000 francs ; and all Thu- ringe gained annually three tons of gold by this culture.f The towns principally supported by this commerce were Erfurt, Gotha, Langensulze, Tenstaedt, Arnstadt, where are still to be seen the ruins of the mills and mill-stones which are used to grind the pastel. The cities of Erfurt and Gotha alone preserve some remains of this ancient industry ; and the first sold pastel in 1798 to the amount only of 8,000 rix dollars. We possess but few historical records upon the culture and commerce of pastel in Italy. It only appears that the court of Rome, for the encourage- ment of this kind of industry, prohibited, in the year 1652, the use of indigo in all its states.J The cultivation of pastel in England does not extend to a very ancient period. Hakluyt § says the English received pastel from France in 1576 ; but that this plant having been introduced into England, grew in perfection, to the great injury of France, the ancient enemy of that country^ "But in 1583, thus was woad brough in and came to good perfection^ to the great leoss of the French^ our old enemis,^^ There is a very ex» traordinary fact reported by Stow, in his Annals, ^ Isatis herba, spm de Culturas Isatidis, etc. 1555. t Beckmann, Anleitung zur Technolagie^ p. 128. fucuL ausg. t Bfckmaiin, Peyt, der Ernnduiigen, vol, iv. p. 529. § Voyages, 2, 161. Edit. 1599. 7ft and by Hume 5 it is this : Qaeen Elizabeth one day having been struck by the disagreeable odour which was produced from pastel in a state of fer- mentation, published an edict prohibiting to all persons the cultivation of pastel. This queen would have made a pleasant code of laws, if, from a sentiment of refined delicacy, she had pro- hibited every thing which was not agreeable to her senses. But this ridiculous prohibition is no longer enforced ; and the English, now better informed, cultivate pastel in sufficient quantity for their own consumption; and if the quality is not as good as that of Lauragais, it nevertheless appears to an- swer their purpose. The most remarkable epoch in the history of pastel is that in which the Emperor Napoleon proposed a prize of 100,000 francs to any person who should find out the means of extracting from pastel a coloring flocculi possessing the fineness of indigo, and susceptible of producing a perma- nent color. Here follows the programme, pub- lished by the government on this subject, under date of July 4th, 1800. PROGRAMME of a prize proposed by or-- der of His Majesty^ the Emperor and King^ for supplying the place of indigo in dyeings as well from the products of the soil of France^ as from those of industry It cannot be dissembled that the discovery of ihe New World, if advantageous in developing 71 coBimerce and navigation^ it has been injurious to several brandies of agriculture^ and European in- dustry- Cochineal has almost extinguished the cultivation of kermes^ which produced a more per- manent^ but less brilliant red. Cotton has taken the place of flax^ silk and wool^ for a great part of our fabrics. The dye-woods of America have been substituted for the produces of the soil^ or those of our industry. But of all the products of the New Worlds there is not any thing which has been so fatal to our agriculture^ as that of indigo^ Before this coloring production was imported into Europe^ blue was dyed with pastel ; a plant which was cultivated in all parts of our continent. As the pastel of the middle climates was very supe- rior to that of the northern^ the south of France^ and particularly in the environs of Toulouse^ were supported by this culture. The commerce of pas- tel had become of such importance^ towards the end of the sixteenth century^ the period when in- digo began to be known^ that there was exported generally 200^000 bales per annum^ weighing 200 pounds each. This commerce being so advanta- geous to agriculture^ that the country of Laura- gais^ where the first quality of pastel was culti- vated^ was called the plentiful country/^ fie pays de Cocagne.J'^ This commerce had so much enriched this country^ that the most elegant edi- fices of Toulouse were built by the cultivators of pastel^ and one of them, Pierre de Bernin gave pledges for the ransom of Francis the 1st. * Cocagne is used figuratively. The literal translation of the word is pastel-cake. 7S The iotrocluction of indigo so iiiiicli alariiied the govern merits of Europe^ on the fate of pasteL whicli formed one of tlie principal branches of com- merce and agriculture^ that they prohibited the use of iodigo^ under severe penalties. Henry IV. pronounced the pain of death against those who made use of it. The sovereigns of Holland and Germany followed his example^ to maintain their pastel establishments^ known in the north under the name of pastel of Erfort^ de Juliers^ &c.* It is probable that if their knowledge had been eqoal to that of the present day^ or the fabrication of pastel had been carried to the same degree of perfection as that of indigo^ tiiis precious branch of agriculture and commerce would have been pre- served. At present the culture of pastel is very limited in France. It is preserved but in a very small part of Upper Languedoc, and in some cantons of the north^ where it is known under the name of vouede. In Upper Languedoc^ the culture of maize has taken the place of pastel^ but so far from supply- ing its place advantageously to the cultivators^ the estates of Languedoc suffer an annual loss of from 5 to 600,000 francs. Pastel is now only used mixed with indigo^ to foment the vats chilled pastel vats. To judge correctly why a preference has been given to indigo, and to acquit Europe for having sacrificed a territorial and natural prodnction, to an exotic one^ it is important to know^ Ist^ that in- * Yoyes cl-dessus, p. 65 et 68 (Note de fauteur.) 73 digo^ such as is in the market^ has been separated by a well known process^ from the other parts of the plant which do not possess a coloring princi- ple^ and^ consequently^ the same bulk produces more dye than pastel^ the coloring principle of which is mixed with the bruised fragments of the plants^ which renders the use of it difficult; the vats are not so rich in coloring matter : and it is necessary to renew the dye at every operation^ whereas those of indigo last a year. Sd. The color of indigo is more lively than that of pastel^ and answers better to make the different shades of blue. It can be said in favor of pastel that it produces a more permanent color, and that it is even capa- l)le of giving a very brilliant blue ; for our an- cient dyers formed with pastel alone the excellent blues, called Persian blues^ of which the historians speak^ and which gave a reputation to our colors in the Levant. It is only necessary then to improve the prepa- ration of pastel, so as to equal, and even surpass the qualities of indigo ; and the first means consist in extracting the coloring flocculi. The know- ledge of the process employed to extract the floc- culi from the indigo plant, and the results which have been produced by men of merit who have treated pastel in the same manner, induces us to found solid hopes upon the solution of this problem. Instead of cutting the plant three or four times in a year, as has been customary, it is only necessa- ry perhaps to let it mature, to produce a more perfect and abundant flocculi^ and of less difficult extraction. 7 74 By emcoiiragiDg and perfecting tlie culture and preparation, of pastel^ His Majesty has not believed it necessary to neglect other means to replace^ or at least diminish the consumption of indigo. He has tliought^ that 131 the present state of our know- ledge^ it is only necessary to give a direction to the talents of our country towards a great object of public utility^ to promise himself great results. Already the fabrics of Lyons are advantageously dyed a beautiful color with Prussian blue, and it is to be hoped that its use can easily be extended to woollen cloths. It is believed, then, that the researches should be conf],ned to the latter, because this magniiicent color, the most rich and most brilliant which is known, although it is not affected by the air, wa- ter, or acids, still is not of a nature to resist the action of the lies to which linens and cotton manu- fiictures are submitted. If the intention of His Majesty be fulfilled, as to pastel and Prussian blue, no doubt they will infinitely surpass indigo ; but to give to this im- portant question all the extension of which it is susceptible, His Majesty wishes to be assurecl if, upon the immensely extended soil of France, as various in its productions as the temperature of its climate, there does not exist some plant besides pastel which will furnish a flocculi analagous to indigo, or some vegetable blue which can be per- manently fixed on cloths. This is the subject of two prizes, the importance of which will be per^ ceived by all those who appreciate discoveries ac- cording to the degree of their utility. 75 IMPERIAL DECREE. In consequence of the report which has been made to us^ of the means which can be employed to diminish the consumption of indigo in dyeings as well from the products of the French soil;, as those of industry^ We have decreed^ and do decree as follows : TITLE FIRST. Art. 1st. There will be awarded a prize of 4OO5OOO francs to any person who shall discover the means of extracting from an indigenous plant;, and easy of cultivation, a floccuii proper to supply the place of indigo^ with regard to the price, the use, the brilliancy and solidity of its color. Art. 2. An equal prize will be given to any person who shall furnish a process proper for fix- ing an indigenous vegetable color upon wool^ cotton, linen paid silk;, in a manner^ to supply the place of indigo^ agreeably to the conditions of the first article. Art. 3. A prize of 50^000 francs w ill be award- ed to any person^ who^ by mixing indigo with an indigenous substance^ or by using it in a new manner^ shall diminish the quantity one half, and produce nevertheless the same effect^ both as to the perfection of the color and its permanency. A prize of S5,000 francs will be awarded^ if the quantity of indigo is diminished one quarter^ upon the same conditions as above. ^6 TITLE SECOND. Art. 4. There will be awarded a prize of §5^000 francs to any person who shall find out an easy and sure method of extracting from the pastel plant^ (isatis tinctoria^ Lin.) the coloring floccnli^ and the means of using it in dyeing. Art. 5. A prize of 100^000 francs w ill be award- ed, if there can be obtained or given to this floc- euli^ without injuring its solidity the fineness and ferilliancy of indigo. TITLE THIRD. x4.rt. 6. There will be av/arded a prize of 23^000 francs to any person who shall make known a sure and easy process to color wool and silk with Prussian blue ; the manner of obtaining an uni- form^ brilliant^ eqoal^ and unalterable color^ w^hich shall not change by wear or washing. Art. 7- The competitors must address to our minister of the interior^ a description of their pro- cesses^ accompanied with a sample of the stuffs dyed^ or the prepared materials^ in sufficient quantities to verify the process. Art. 8. Our ministers of the interior, and of the public treasury, are charged with the execu- tion of the present decree. Signed, NAPOLEON. By the Emperor^ the Minister Secretary ofState^ Signed. H. B. Due de Bassako^ 77 CHAPTER II. Analysis of Pastel^ {isatis tinctoria^ L.) and of its coloring flocciili. Although the identity of indigo is the same in indigo fera^ and pastel^ it is best^ nevertheless^ to know and compare the divers analysises wiiich have been made of the coloring flocculi of these two plants^ in order to form a correct idea^ and to point out a less uncertain method of making ex- periments for obtaining a greater quantity of floc- culi from pastel. We will therefore give the analysis of pastel; and its flocculi^ published by M. Chevreul. ANALYSIS OF ISATIS TINCTORIA, PASTEL, BY M. CHEVREUL. From three hundred £:rammes^ of the leaves of pastel^ were expressed a green juice^ very thick and mucilaginous. The expressed leaves were bruised several times^ then watered and pressed again in a linen cloth. All the united juices were thrown into filters^ which were covered with panes of glass to prevent the contact of the air. There remained upon the paper a green substance, which the ancient chemists called "fecide verte^^ green flocculi. To be more methodical in our labors w© shall examine successively. * About ie,-? oiinces. ^7 7B 1st. The expressed and filtered juice. 2d. The green flocculi. 3d. The expressed matter^ formed priEcipalij of the iigneous fragments of the plant, SECTION L Examination of the Filtered Juice, \ ARTICLE I, A. It had a yellowish color inclining to red ; was slightly acid ; became greenish by exposure to the air^ and covered with a brassy pellicle. Twenty-four hours after the first filtration^ it was filtered again^ to separate the sediment which had collected. There remained upon the paper a blue substance^ which emitted a purple vapor when exposed to heat^ which dissolved in sulphuric acid and coloured it blue. This matter then was in- digo, which being precipitated from the liquor^ absorbed oxigen. B. The juice separated from the indigo was red and a little acid. The acid separated from the vegeto-animal matter, developes a green color. This phenomenon indicates the presence of the matter which I have found in the indigo of Java^ &c. and which I have called "green matter The alkalies, and the alkaline earths, change the color to yellow, and ammonia is disengaged. The juice, exposed to heat in a porcelain ves- sel, presents the following phenomena : at 104^ "degrees^ there are formed small white points. 79 wiiicli gradually increase and soon form mto fila- ments. At 140^ the coagulation appears com- plete, the liquid becomes clear^ and assumes a reddish color ; this was the only ciiange which ap- peared after the action of the heat. The separation of a solid matter from a liquid perfectly clear, is a fact well worthy of attention : is this effected by an union of the particles, pro« duced by a force analagous to that which collects into chrystals, saline particles dissolved in a liquid ; or does it contain a substance which com- bines with the animal matter which renders it insoluble, as happens with cheese, which coagu- lates spontaneously in milk ? Without deciding in favour of either of tliese two opinions, it appears to me certain that the contact of air is not neces- sary to produce this coagulation. JBut let us examine the properties of this coagu- lated matter. It is green in some parts and red in others : it was almost entirely discoloured by boiling'hot alcohol, which dissolved from it "green matter and a little indigo ; in this state it was white, but turned brown on being exposed to the air. It would not dissolve in hot water : exposed to heat it melted, swelled, and gave the same products as animal matter. The ashes of its carbon were blueish, consisting of the jphos-- j)hate of lime and iron^ carbonate of lime^ and a small quantity of st'Z^'^; nitric and oxalic acid gives it a bitter taste. It was dissolved by acetic acid. C. The liquor B. separated from the vegeto- animal matter by the filter, was evaporated to the consistence of clear syrup. During the evapora- tion, flakes of the animal matter were deposited^ 80 and particles of yellow extractive matter* Alcohol was turned on the evaporated liquor^ to separate every thing contained in this menstruum which was soluble. The matter dissolved by the alcohol was of a fine rose color; it was acid; it was concentrated; it was then washed in water^ to separate tiie alcohol from it^ and again concentrated ; w hen the evapo- ration was completed^ it was precipitated from the green matter. This precipitate had the ap- pearance of a thick oil : spread on coals it gave an odour uniting the disagreeable with the aroma- tic : it produced carbon of a swollen appearance; it was almost insoluble in water. It was dissolv- ed by alcohol^ with the exception of some flakes. green matter resembles that which I have described in my Memoir upon Indigo. But I will remark here, that it does not assume a green color unless united with an acid ; it appears of a redish yellow in its pure state^ and is red when united with alkalies or alkaline earths. I have satisfied myself in the following manner^ why it assumes a green color when mixed with acids. I com- bined with it a certain quantity of potashes^ and turned by degrees sulphuric acid on this ; tlie red color w as weakened and approached to yellow ; at this time it had a slight excess of acid. If the green matter had been of this color in its pure state^ it shoiild have appeared of this hue from the moment the alkali was saturated ; and this did not happen : for to change it to green it was ne- cessary to add a larger quantity of acidi, which satisfiictorily proves that it is necessary to pro- duce its color* 81 This experiment perfectly explains why the juice of pastel^ coagulated by heat and filtration^ has a rose color^ although it contains a slight ex- cess of acid ; and why this juice^ mixed with al- cohol^ and then evaporated^ leaves a sediment of ''green matter. In the first case^ the acid is too much attenuated to react on the "green maU ter but by concentration^ its energy is augment- ed^ and it then forms a green combination with this substance; perhaps it is thus formed from the acid by the action of heat. I presume it ig the acetic acid which produces this phenomena. Although the name of green matter is improp- er to designate this substance^ I preserve it^ be- cause it is better known. The liquid separated from the "green mattery^ being of a brownish red^ all the acids changed it togreen^ and precipitated a matter combined with green ; the alkalies changed it to red^ mixed yellow, as it has a little yellow extractive matter^ of which we shall speak presently. This liquid contains muriate ofammonia^ which is discovered by the alkalies and the solution of silver ; nitre mixed with the muriate of potash^ is discovered by evaporating it to dryness^ and by the operation of alcohol ; besides the muriate of ammonia^ vvhich was dissolved^ there was a little acetate of potash^ which is separated from the acid by distilling it with weak sulphuric acid;> and from the potash by incineration. Alcohol then separates from the evaporated juice of pastel^ 1st. The green matter. 2d. The yellow extractive matter. 3d. The acetic acid^ which does not probably color the green matter^ 82 as it is too much extended ; but by concentration it unites with it and the precipitate. 4th. Mu- riate of ammonia. 5th. JSTitrate of potash. 6th, Acetate of potash. The nitre and sal ammoniac are in considerable quantities. Lime has not been discovered in this alcoholic liquor^ or by the reactiveso D. The matter insoluble in alcohol^, (C.) was dissolved by hot water. This solution was of a rose color^ and acid did not turn it green^ which proves that it did not contain the green matter. The acid gave it a yellow tinge^ the alkalies a deeper yellow ; silk steeped in this liquor took a yelloAv color^ inclining a little to red. These experiments demonstrate the presence of a yellow coloring matter^ which I believe is analagous to that which exists in several kinds of indigo^ and many vegetable juices. The aqueous solution contained principally a vegetable salt^ mixed with an acid or lime as a basis^ the existence of which was proved by the oxalate of ammonia, and the acetate of lead ; the nitrate of silver was precipitated in abundance by the vegetable acid and coloring matter. This precipitate did not contain muriate of silver ; ih% nitrate of barytes produced an abundant precipi- tate^ principally formed by the vegetable acid, for the ilitric acid did not leave but a very small quantity of sulphate. Nut gall indicated traces of animal matter. Besides these substances^ it contained mucilage^ which I separated from the yelloiv extractive mat- ter with acetate of lead^ by which it was precipi- tated. By passing sulphurated hydrogen gas 83 tiirougli the liquor^ the excess of lead was preci- pitated^ which I concentrated and added alcohol^ which separated from the acetate of lime^ formed by the decomposition of vegetable salt^ and left a viscus matter of a gummy Kiature. I should ob- serve, that I did not obtain inncos acid;, by treat- ing it with nitric acid. E. The small quantity of matter which was not dissolved by hot water in the preceding operation^ was white, and appeared chrystalised. It- was dissolved by water, mixed with nitric acid. From this solution an abundant precipitate was pro- duced, by the oxalate of ammonia and the fixed alkalies. Ammonia produced no precipitate, which proves that it did not contain phosphate of lime. Acetate of lead produced a precipitate formed by the vegetable acidj which was combined with lime and magnesia / for having incinerated a portion of this white matter which was not dis- solved in nitric acid, I obtained a residuum of carbonate of lime and magnesia. The small quantity of this salt did not permit of my separa- ting the acid from it ; but I have reason to be- lieve it was cetrate^ for it had the same appear- ance of that which Messrs. Vanquelin and Four- croy have extracted from the juice of onions, and it being insoluble in boiling water, proves that it was not malate of lime. Water then separated from the juice, which had been treated with alcohol, 1st. Fellow coloring extractive matter. Sd. gummy matter. 3d. Acidulated malate of lime. 4th. A small quanti- ty of sulphate of lime. The vegetable salt which was not dissolved, was supposed to be citrate of lime and magnesia. 84 ARTICLE 11. The preceding experiments not having been made with a view to discover the nature of the vegetable acids^ or the volatile principles contain- ed in the juice of pastel^ the following attempts have been made to effect those objects. A. The juice of pastel,, distilled in a*glass re- tort^ fiimished with a receiver^ gives a white li- quoFj containing 1st. probably an oily principle^ which smells like green kidney beans. Sd, Am- monia ; for^ mixed with acid, it changes turnsole red^ and precipitates the acetate of lead. 3d. Sul- phur ; for paper^ covered over with the carbonate of leacl^ being placed in the receiver in which the ^listillation was made^ becomes covered with black sulphur. I will observe here, that this paper is very good to discover the presence of sulphur, and it is better to expose it to the. fumes arising from the vessel of liquor, than to plunge it into the li- quor itself. I am ignorant whether the ammonia, obtained by the distillation, arises from the decomposition of some vegetable substance, or the decompositon of ao ammonical salt, (the acetate of ammonia for example) this last opinion appears the most prob- able. It is possible that the affinity for the acids of certain vegetable matters, particularly those which contain azote, aided by heat, decides in fa- vor of the decomposition of ammonical salts. B. The juice of pastel, distilled with weak sulphuric acid, produces a liquid, which contains acetic acid. Perceiving that the fumes from the S5 vessel had tlie smell of priissic acid^ I put potasli in the receiver^ and inimediately green sulphate of iron was precipitated ; I then poured weak sulphuric acid on it, and obtained a blue matter^ easily known as the prusiate of iron. After this experiment^ there can no longer re- main a doubt of the presence of prussic acid in the product of distillation. But is all this acid entirely formed in the plants,, or is it developed by the aid of heat and sulphuric acid ? These are questions which I cannot resolve in a positive manner^ but the first opinion appears to me infinitely the most probable. C. The juice of pastel^ separated from its vegi- to animal matter by heat^ v/as precipitated by the acetate of lead 5 I obtained an abundant sedi- ment of a yellow color^ formed of vegetable acid united first with lime^ the yellow extractive mat- ter, the green matter and a small quantity of veg^ ito-animal matter ^ which had escaped coagulation. This precipitate^ decomposed by sulpluiric acid^ produced a vegitable acid which presented the fol« lowing properties. By evaporation it is covered with pelicleSj^ which are produced by the reaction of the acid upon the extractive matter^ &c. which was preci- pitated with it. It can be deprived of the greater part of this substance^ by evaporating it several times, and afterwards treating it with alcohol at 143^. The acid purified in this manner^ and left to itself for a month and a half, did not crystal- ize ; w ater being added at this time, there were still separated from it some flakes of yellow ex* tractive matter^ changed by the acid; and the li« 8 86 qiior presented tlie following cliaracteristics. Lime water produced no precipitate^ but the water of barytes did ; and the precipitate w^as totally re- dissolved in water. These re^actives caused the acid to assume a yellow color^ as it still contained a little yellow extract. Potash made the color darker^ but did not produce cream of tartar^ al- though there w as a great excess of acid. Nitrate of barytes made no precipitate^, but one appeared by adding a drop of ammonia. The muriate of lime produced a precipitate soluble in cold water ; the nitrate of silver a precipitate^ soluble in nitric acid ; the nitrate of mercury^ the acetate of lead^ white precipitates. The last was dissolved by acetic acid^ but it required a certain quantity. . From these characteristics^ I believe that the acid of pastel^ which is combined with lime^ and which dissolves in water^, after treating the juice of pastel ynth alcohol, is malic acid. The liquor which had been deprived of its pre- cipitate by the acetate of lead^ and then exposed to sulphurated hydrogen^ was evaporated ; when it was sufficiently concentrated^ it was put in a cool place, and at the end of some hours, produced crystals of the nitrate of jwiasli. The water in whicii the crystalization took place^ became red- dish ; it contained considerable acetate of lime^ and acetate of ammonia^ acetate of magnesia^ ace- tate of potash^ and a muriate. These salts aro produced by alcohol at 142^. The residue insoluble in alcohol, was almost entirely dissolved by water ; there only remained a white matter like starch. It may be the same salt which I have supposed to be citrate | ■ water 87 dissolved from the giimy nitre and lime. I am ignorant with what acid the last was combined* The red color of this solution^ did not arise from an extractive coloring matter., for the acetate of lead^ and the muriate of tin^ produced no precip- itate ; I think it originated from the re-action of the salts upon the vegetable matter. SECTION II. Examination of the green flocciili remaining on the paper after the filtration of the juiee. A, Wlien this flocculi was quite fresh^ green rosin was the principal product^ after several ma- cerations in alcohol. Afterwards it was macera. ted several times with hot alcohol ; by this means the waXp indigOy and green rosin which it con- tained^ were dissolved. The wax separated by cooling, and the indigo was precipitated at the end of some hours. It sometimes happens that the wax contains a little indigo. I believe the best method of separating these three bodies is the following. Filter the hot alcoholic liquor^ and when it cools, the wax will separate from it. Then filter it again, and leave the liquor exposed to the air in a glass vessel ; at the end of fifteen or tAventy hours, the indigo will be precipitated at the bottom of the vessel. Decant the liquor, and wash the sediment in cold alcohol, in order to separate the green rosin, which may be mixed with the indigo. The alcohol, from which the indigo is precipitated, contains a little of the lat- ter, in consequence of the green rosin. 88 B. As to tlie matter insoluble in alcohol^ it is found to consist of the vegito-animal matter^ sep- arated from the indigo^ and the green rosin^ and in greater quantity^ when the green flocculi^ of whieh we have treated^ has been much dried. Alcohol cannot separate these two substances^ as they are united by the same force which causes in- digo to adhere to woollen cloths. Besides the an- imal matter^ there is a melange of woody fibres^ which^ in consequence of its division^ had passed ihrough the cloth^ which had been used for ex- pressing the bruised plants. When the green floccuii was operated upon by hot alcohol^ green rosin and indigo were separat- ed at the same moment ; but when the quantity of rosin is in excess^ the greater is the quantity of indigo held in solution. When it is desired to dis- cover the presence of indigo in the floccuii^ I be- lieve it is best to treat it first with cold alcohol^ in order to dissolve the greatest possible quantity of green rosin. SECTION IIL Examination of the expressed leaves of PauteL A. The woody fibres of expressed pastel^ which were mixed with the green floccuii, was divided into two portions. The first produced ashes which were leached ; it contained a great quantity of the carbonate of potash^ besides tliQ sulphate^ muri- ate, and phosphate of potash. These salts were discovered w ith the ordinary re-actives. 89 The residue of the ashes insoluble in water^ was dissolved by effervescing it v^ith muriatic acid^ except a small quantity of silea? and carbon^ which had escaped combustion. The muriatic solution evaporated to dryness^ was put into alco- hol;, which separated the muriate of limep magne-^ sia and ii^on. The matter insoluble in alcohol was dissolved by nitric acid ; this substance Gouitdned j^Jiosphate of lime^ mangan ese^ united^ probably^ to the phos- phoric acid^ and a little iron. The presence of manganese was indicated by the prusiate of pot- ash; a white precipitate was obtained^ a little blueisli^ in consequence of the iron it contained. The small quantity of these substances did not permit me to see whether there was any phosphate of magnesia. B. The second portion of the expressed leaves being put into hot alcohol, there was obtained waiv^ a small quantity of indigo red substance^ (of which I shall speak hereafter) green rosin and nitrate of potash. It is this last salt which fur. nished the greatest part of the alkalie, which was obtained by the combustion of pastel. The leaves of this plant contain it in such large quantities, that when they are dry, it is only necessary to heat them red hot, to see the nitre fuze with the carbon of the vegetable. I think that the phos- phate of potash obtained by the preceding incine- ration, proceeds from the decomposition of some earthy or metalic phosphate. C. The portion (B) after the alcohol was drain- ed out of it, was put into muriatic acid, with the intention of discovering whether it contained the *8 90 oxalate of Imie ; but haviDg gatorated tlie excess of acid with ammonia^ I did not obtain this pre- cipitate in grains which attaches itself to the sides of the vessels^ and which characterizes the oxa» late of lime. The muriatic acid^ in other things hokls considerable lime in solution^ which pro- ceeds from the malate. It is beyond a doubt that the ©arbonate of lime does not proceed from the decomposition of this salt. The stalks steeped in muriatic acid^ w^ere col- ored in some parts a very fine blue^ in conse- quence of the indigo which was combined with it. These stalks^ when incinerated^ produced white ashes princi|)ally formed of silex. 91 Summary of the Analysis of Isatis Tinctoria , I. Juice of PasteL Indigo in small quantities Vegito-animal matter - - Obtained by oxidination^ heat. II. Green FlocciL IL III. pressed leav es. Sulphur - - Odoriferous oil Ammonia - » « . - 1 heat and Acetic acid - - - - - > sulphuric Prussic acid - - - - } acid. Green matter - - - j Yellow extractive matter Nitrate of potash - - . ! Muriate of ammonia - - } alcohoL Acetate of potash - - » Muriate of potash ... Acetic acid - - . . - Gum - - Yellow extractive matter Acidulated malate of lime y water. Sulphate of lime Citrate of lime and magnesia, f Green rosin - - - - - ^ I Wax j <( Indigo alcohoL I Vegito-animal matter I^Ligneous - r Green rosin . . - Wax .... / Indigo - ^ Nitre ... - Red matter - - . Salts - - - . - SECTION IT- Of the state of Indigo in vegetable$. CONCLUSIONS. I conclude from the preceding facts,, Ist^ That the indigo is perfectly formed in the vegetables^ and in that state^ is at its minimum of oxidination^ or at least nearly so ; for it is not impossible that it may be saturated with a portion of oxygen^ which is left to be ascertained by ul- terior experiments. Sd^ That the various processes which indigo fera undergoes^ are intended to separate the indi^ go from the substances to which it is united^, and combine it with oxygen. 3d^ That indigo should be thus characterized^ composed immediately of vegetables^ white at its minimum of oxidinatioui, does not then color sul- phuric acid blue. Purple at its maximum of ox- idinatiouj, then colors sulphuric acid blue^ capable of being cryatalized in needles ; volatile^ emitting a purple vapor. CHAPTER III. Different processes which have been employed to extract Indigo from PasteL It was early thought that pastel, treated as in- digofera, would give the greatest quantity of col- oring fiocculi; and be more easily and economic 93 cally lilted in dyeing. Divers , processes were therefore attempted, which we believe to be our duty to give an account of, that those who wish to pursue this useful object, may be able to un- derstand the errors of those who preceded them^ and advance with a more sure and rapid step, by having under their eyes the different discoveries which have been made down to the present time. This matter was thought of so much importance by two learned societies, that they made it a sub- ject for a prize. That of Gottengen proposed one, and that of Turin another, in 1791. We shall in this chapter relate the results of the dif- ferent experiments which were made. Astruc is, to our knowledge, the first person who published this idea. After speaking of the inconveniences of pastel in the operations of dye- ing, he adds, I know only one way of remedying it ; that is, to prepare pastel in the same manner that in- digo is prepared. That will give the same lus- tre and sprightliness to the colors, produced by pastel, as those dyed with indigo, without, in the least, diminishing that excellency and permanen- cy of color, produced by pastel, whieh renders it so particularly preferable.^^ " I have already made some small experiments in the manner above proposed, and these experi- ments have not only assisted me, in the prepara- tion of the powder of pastel, but also in the use of this powder of pastel, &c.^^^ * Mem. ponr servir a 1' Histoire naturelle du LanguedoCs in 4to. 1637, p. 331. 94 It is to be regretted that A struc had not made his process knowri;, if he really obtained advan- tageous results. The idea of extracting the flocculi from pastel^ had been proposed;, about the same time^ by Hellot.^ It is said^ in the writings of Halie^, published in 1754^ that the counsellor of the Barth mines^f who was occupied two years in endeavoring to extract the flocculi from indigo^ at last obtained a happy result ; and that this flocculi was equal in beauty^ durability^ and its coloring quality^ to the best indigo of India ; that the colors dyed with it^ resisted acids^ alkalies^ the sun^ frosty rain^ windy and washing. It has^ besides these advantages^ that of being used without the addition of the pre- pared or unprepared plants of pastel. This pro- cess requires less labw^ and can be executed by less skilful persons. This fine discovery^ an- nounced with so much emphasis^ is of the same character as that of the multitude of new inven- tions and discoveries which daily fill the papers of Europe^ and proves how often the most able chemists are deceived^ or wish to deceive the public. Schreber^j who prepared a treatise upon pastel^ and who had been much occupied in the culture, preparation and use of this plant, affirms in a col- lection of observations, commenced in 1755^ that he obtained, by fermentation, a flocculi equal to L' Art de la Teinture ties Laines, p. 224 et 237. t He is the same person who discovered, or at least per* fected the preparation of Saxon blue. J Sammiuiig Verohidener Schriffteo^ 1755—64, abth. IS. that of indigo^ and that he would prove it to those who wished it. It appears that the attention of the German phi- losophers was especially directed^ about the mid- dle of the eighteenth century^ toward the means to be used for the extraction of this flocculi. Ku- lenkamp^ of Bremen, labored several years, and at last succeeded, after having made several fruit- less attempts. We will relate th^ two processes employed by Kulenkamp, as described in a me- moir approved by the royal society of sciences of Gottingen.^ Tins learned German has been able to extract the coloring flocculi from pastel, by divers means ; but he has made known but two ; the others being too difficult to execute, or too expensive. The first process is analagous to that employed in the preparation of indigo^ and requires great atten- tion. Water is heated in a cauldron, to a tempe- rature of 100 degrees of Fahrenheit and kept as near as possible to that degree, during the time of fermentation, which is that of the atmosphere in the islands where indigo is prepared. The caul- dron is filled with the leaves of pastel. At the end of three hours it exhales a disagreeable odour<, the water becomes of a pale green color, and these appearances become more visible every hour. After ten hours fermentation, there is collected, on the sides, a blue froth ; and two hours after, the water is saturated with all the coloring matter; which can be known by taking out a part of the liquor in a glass, to which lime water is added * Description des Arts et Metiers, &c. Art de f lodigolier, edit, de Neufchatel, in 4to. 98 and a precipitate is deposited. If tlie water is not then im.meclipiely drawn ofF^ tlie odour. be- comes fetid^ and the quantity of floccoii is less and of asi inferior qaality. The second process is more simple and more easily executed. The water in the cauldron is made to boil^ and as soon as the ebullition ceases^ the leaves of pastel are put into it^ and the water is then kept np at a high degree of heat^ without boiling. The whole is stirred up often ; after it has subsided for a half an hour^ a cock at the bot- torn of the cauldron is opened^ to let off the liquid into a vat one third full of lime water. This wa- ter is com.posed of one part of quick liine^ to two hundred parts of fountain water. It is stirred often^ to laciiitate the precipitation of the coloring particles. The olive green color of the liquor changes to a beautiful deep green^ and a blue froth appears on the surface. It is left then to re- pose^ and the coloring particles are precipitated to the bottom of the vat. The sides of the vat are pierced with holes at different heights. At the ex- piration of an hour the holes are opened to let off the yellow water above the precipitate. Hie vat is then fdled with cold water, which is violently stirred with the sediment to separate the lime and the yellow particles. A white froth is then form- ed which runs over the vat^ but this may be pre- vented, by pouring into it some drops of oil, or isinglass. The water should be draw n off as soon as the precipitate has been deposited, otherwise a fermentation will take place, and the blue flocculi be injured. The second water is drawn off from the vat, with the flocculi, and put into large earthen %7 jars ; a little sulphuric acid is mixed with it^ in the proportion of one ounce of acid to a bucket of liquid. It is drawn off again after a repose of some hours, as has been said above. It is then washed with another water ; that is then drawn off, and a blue flocculi is obtained, which has the appearance and qualities of real iudlgo. It is to be observed, that when tlie water with the leaves in it is made to boil, the coloring mat- ter is absorbed by the leaves, and it cannot after- wards be separated. This is the reason why it is necessary to keep the temperature below that of boiling water. There will be less of the floc- culi if the temperature is too low. Kulenkamp says he obtained ft'om each crop, produced on 420 square rods of Ln^nd, from ten to eleven pounds of the blue flocculi, and that all the expenses of each cutting amounted to eight crowns We find, in a German author, that Schreber and Munshard have given very exact processes for extracting indigo from pastel. But as tlieir works are not to be found, except in the libraries of the capitol, it is not possible for us to make them known to the public. We will give an ex- tract at the end of this volume, if we receive the books we have sent to Germany for, before the whole impression is finished. Marggraf reports, in a memoir inserted in the History of the Royal Academy of Sciences, for the year 1764, page 18, some experiments which he had made to extract the flocculi from pastel^ from which we extract the following. After having put the leaves of pastel in a vat, and put weights upon them to keep them under 9 S8 the water in wbich tliey were soaked^ the vats were covered over, and exposed in the air during the season of the greatest lieat. The water be- came putrid at the end of several days ; there arose to the top a blue pellicle which was taken oflj and others were successively formed. These pellicles produce a coloring pigment^ as does the water after it is drawn off from the mass and left to subside ; but it appears that this method is too long and too minute to be employed on a large scale. Marggraf proved that the blue color of pastel is not contained in those parts of it which a.re so- luble in water^ or in its gummy part 5 but in the particles which are insoluble inwater^ and which^ separated from the leaves by putrefaction/ are precipitated to the bottom of the water. He took fresh leaves of pastel and boiled them in water ; and after draining off this water which was of a brown colour^ he pressed the leaves^ then boiled them again^ and then pressed them^ and continued this operation until the water which w^as usecl came away perfectly limpid. The residue hav- ing been em,ployed to form an indigo vat, accord- ing to the method indicated by Herbellot^ the color produced on woollen cloth was as good as that from common pastel. Professor Blauer extracted tlie coloring floccuii from pastel. But as his experiments contain nothing particularly interesting;^ we shall only in- form those persons^ who wish to consult them^ that they are to be found in German^ in the Acta Acad. Elect. Magimtina^ for the year 1778^ p. 34^- Gren, in the year 1780^ gave a description of 99 im operations wliidi be made use of in a German manufactory^ to extract the flocculi from pasteL We will relate those contained in the Elements de Teinture de M. Eerthollet. Take the fresh leaves of pastel^ wash them in an oblong vat to cleanse them of the salts and earth; to prevent the leaves from rising upon the water*, confine them by transverse pieces of wood. After the first water is drawn off, pour on to the leaves a sufficient quantity of water to cover them entire- ly^ and put the vat in a temperate heat; there will be formed in a greater or less time^ accord« ing to the temperature of the atmosphere^ a co- pious foam on the surface of the water^ which is an indication of the commencement of fermenta- tion. The surface of the vat is by degrees en- tirely covered with a blue pellicle or skin^ which presents to the eye shades of a brassy color* When there is a certain quantity of this foam^ the liquor becomes of a deep green color^, and is flrawn off into another oblong vat, by means of a hole in the bottom of the vat. In both cases it is neces« sary to let the water pass through a cloth into the other vat^ to separate the salts and small portions of leaves^ which otherwise would pass off with the water. Wash the leaves in a little cold water to separate the particles of coloring matter which may be attached to them^, and mix this water with the other. This done^ turn into the liquor of fer- mented pastel^ lime water^ at the rate of two or three pounds^ to ten pounds of leaves^ and agitate the liquor violently for some time^ to facilitate the separation of the indigo^ which will be deposited when left undisturbed. To ascertain whether the 100 ;agitation lias been continued a sufficient time^ take a part of the yellowish liquor in a common bottle^ and see whether^ by violently agitating it^ more blue matter is separated^ if so^ agitate the liquor again. When all the indigo is separated and de- posited^ the water is drawn ofi*. which should be done without loss of time« The blue color is turned into conical filters made of linen cloths* But in the commencement of filtration^ there al- ways passes a little of the coloring flocculi^ which bIiouM be received in a vessel placed underneath^ and turned back into the filters until the water runs oif quite clear. Edulcorate the indigo con». tained in the filters with a sufficient quantity of water^ and put it in the shade to dry^ where there is a slight degree of artificial heat^ taking care to cover it over. Indigo is obtained without the addition of lime W'ater^ but much less. If a large quantity of lime water is added^ the quantity of indigo^ it is true^ is increased^ but it is of an inferior quality^ as the surplus of calcareous earth unites with the indii go. Alkaline salts fecilitate the separation of the blue color^j but it is not advantageous to use them^ tliey afterward dissolve a part of the pigment, lly the addition of an acid no precipitate is made* It is proper that a certain time should elapse before the water is drawn off^ which fermented with the leaves ; if it is drawn off too sooo^ but little indigo is obtained ; if^ on the contrary^ the leaves are left too long in the water^, they easily become putrified^ and exhale a putrid . volatile odoor^ peculiar to pastel. When no more pre» cipitate can be separated; the water constantly re- 101 mains green. The liquor^ when drawn off^ is left undisturbed^ and even the indigo^, when sepa- rated from the liquor^ will become putrid ; the latter should be prevented from putrifying^ if not^ the indigo, or a part of it^ will be destroyed at least. It will not do^ nevertheless^ to be too hasty in drawing off the liquor into the vat where it is to be agitated^ on the first appearance of the blue pel- licle^ as it is at this time^ the water becomes charg- ed with the greatest cjuantity of indigo. When the degree of heat is very great^ fermentation soon commences^ and often eight or ten hours are suf- ficient to produce it. It is then necessary to be very attentive^ not to let it go on to a total putre- faction. If the heat of the atmosphere is not great enough^ " but little frothy or blue pellicles will be seen^ and the liquor insensibly inclines to putrefaction^ without presenting the well known phenomena before it takes place. Bruised plants^ or their juice^ ferment morer rapidly^ but they produce a dirty blue. Indigo^ extracted from pastel^ should be dried in the shade^ as the sun destroys its color. We will now relate the processes employed by Dambourney^ to extract the flocculi from pastel^ as he appears to have obtained the greatest cpantityo The following are the most fortunate results of the divers experiments which he made.^ He put five pounds two ounces of the fresh leaves of pas- tel^ which had come to maturity^ into three buck- * Supplement au Recucil de Procedes sur les Temtores solides, p. 92 et suiv, ^9 10S e ts of water ; at tlie end of four honrs^ tlie fermetit- atioii beiag complete^ he took out the leaves^ and mixed witli the liquid a quart of caustic lie, Th(5 whole being agitated with a sticky and filtered^ produced two ounces of good dry flocculi, resem- bling indigo. The water which M'^as dravv^n off being much colored^ was mixed with a solution of alum^ and produced a slate blue flocculi^ wdiich answered for dyeing. The same experiment was twice repeated on a- larger scale^ to wit^ fifty-two quarts of water^ and thirty-five pounds of fresh leaves were used^ which a;ave eight ounces of blue fl,occuli. From this it appears that ao hundred pounds of leaves w41l produce about a pound and a half of indigo. Dambouroey observes that the experiments^ made with success in the months of July and August^ did not succeed in September^ on account of the cokL The extraction of the flocculi of pastel has been an object of research by the literati and other cha- racters of Italy. Morina^ who cultivated this plant near Naples^ discovered aprocess^ in 1784^ by which he extracted a flocculi nearly equal in quality to that of the indigo plant. And from ex- periments which were made upon it by the Aca- demy of Turin,^ the following were the results^ 1st. Tiiat the color of this indigo was as beautiful as that of American indigo, 2d. That when em- ployed cold in dyeings it produced the same ap- pearances as the last. 3d. Silk^ which had re- ceived a green color^ was instantly changed to * Notizie pablkate per ordine della R. Acad, deile Scienze di Torino, etc, 1791, in 8vo. p. 25., 103 blue. 4th. Cloths^ without any preparation^ took s fine azure color. 5th. Linen and cotton cloths w ere died a fine royal blue. 6th. Mixed with sulphu- ric acid^ it communicated its color to stuffs nnire readily than the same preparation made with com- mon indigo. In the report of the Society of Sci- ences of Turin, there is no statement of the quan- tity of flocculi obtained ; similar experiments were made with success at Milan. 1 he same society informs us in its Memoirs^ that M. the Count Saint-Martin, had endea- voured to dye with pastel and urine without indi- go, w^hich no other person probably had yet done^- and succeeded very well in this attempt.-'^ Many other experiments of the same kind could be cited ; but as the inventors have not made known their process, or the process not being valuable, we believe it our duty to be silent upon them, and attend to only such repeated ex- periments as have given profitable results. We shall finish this chapter by publishing the results announced in a report made to His Ex- cellency, the Minister of the Interior,^ by the commissioner named to decide upon the experi- ments which were inade upon indigenous sub- stances proper for dyeings and answering a$ s uhstitutes for in digo. Sir, The decree of His Imperial Majesty of the 4tli of July last, relative to researches to be made for replacing indigo in dying by the products of our soil and our industry, has excited, throughout Inscri dans le Journal de i'Empire, le 81h Octobrej 1810, 104 France^ tlie most lively enthusiasm.. Tiiree moiitlis have scarcely passed since its publication^ and al« ready a great number of competitors have sent to your Excellency accounts of their experiments^ which we have examined with care^ and which in« duces us to anticipate the most happy results. Agreeably to your earnest request^ we hasten to maice known to you^ in this provisional report^ the results which have been obtained for supply- ing the place of indigo in dyeings diminishing the consumption of it^ or making with Prussian blue^ by an easy process^ a color equally intense and brilliant. 1st. The department of Tarn, which from its position^ and the kind of culture it possesses^ and on which it has^, for a long time^ been dependent for all its opulence^ has been more particularly interested in the solution of the problem on pasteL It has also been the first which attempted with great zeal to discover the means of separating the . foreign atid useless matter^ which^ even at the present moment^ has prevented its being used in dyeing. A commissioner named by the prefect of the department^ and whose labors have been con- stantly stimulated by his presence^ have made a great number of experiments upon this interesting subject. Two of its members^ Messrs. Lamothe- Limousin^ an apothecary of Alby^ and Rouque^ a dyer of that city^ have sent to your Excellency^ with very precise descriptions of the processes they employed^ samples of very fine indigo ex- tracted from pastel ; having all the characteristics of indigo, and several yards of blue cloth colored with this indigenoos iocculi^ which presents ave- 100 fj fine color^ fend as permanent as that dyed witli indigo, Sd. (This article merely relates to a request for further instructionsc) 3d, If the experiments which have been made upon Prussian blue to combine it in a solid man- ner, with wool and silk^ have not yet been suc- cessful^ they have, notwithstanding^ led to new and interesting results^ as it respects silk^, to which it can be very usefully applied as a dye. M. Raymond, a very distinguished professor of chemistry in the city of Lyons, has been able to give to silk a very fine color, with Prussian blue. This scientific man was not content to send a clear and precise description of his process, but came himself to Paris, where he has put it in practice^ under the eyes of one of the members of the com- mission, and uniformly obtained an equal and brilliant color, unalterable by water, or washing, and which answers all the purposes proposed by the 3d title of the decree of his majesty^ upon dye- ing colors. M. Roard, director of dyeing for the imperial manufactories, who has been also engaged in sim- ilar experiments, has met with the same success as M. Raymond, by following a little different meth- od, but which produces results as perfect and as advantageous. Please to accept. Sir; the homage, &c. &c. (Signed) CHAPTAL, THENARD, a L. TRENAUX, GAY-LUSSAa 108 CHAPTER IV. The use of Indigo and Pastel in Dyeing, There are bo,t few of the arts^, tlie principles of ¥/Iiich are so little kiiown^ as that of dyeing. The processes are generally complicattd^ and very difficult to put in practice. The use of indigo and pastel offers a daily example. Great skill and experience are requisite to manage with success an indigo vat. The most experienced workmen sometimes fail in this kind of dyeings without be- ing able to discover the causes which prevents their success. This process has not been sufficiently attended to^ and the principles are not founded on ideas sufficiently certain^ to enable us to controul all the circumstances^ and reach with certainty the proposed object. As our work is principally intended for such persons as wish to make researches upon substan- ces for coloring blue^ and as it is necessary for them to possess all the information that has been collected on this subject^ in order to produce^ with more ease and certainty^ satisfactory results^ we shall state the processes generally employed for dyeing with indigo and pastel ; also relate other means less used^ and give some hints relative to blue dye^ made v/ith pastel^, without the addition of indigo. We shall commence with the process- es employed in the indigo and pastel vat^ as they have been described by M. Berthollet,^ Those ■ ^ Elemes de f Art la Telntiire, 1804^ i 1, p. 69. 107 persons wlio desire more detailed directions on this sulyject^ can consnlt P %irt de la Teinture des Laines^ (the art of dyeing wool) by Hellot^ wiio has particularly described the processes employed in the indigo and pastel vats ; alsO;> P Instruction siir V Art de la Teinture^ (instructions upon the art of dyeing) by Poerner ; and the memoir of M. Dijonval^ approbated by the Academy of Scien- ces^ &c. DijSferent processes are made use of for dyeing blue with indigo. We shall relate these processes without entering into the details which are well known by the dyers^ and which can be found de- scribed with great care in the w^ork of Hellot. The preparation for dyeing blue^ is not made in cauldrons^ as for other colors^ but in great wooden vessels^ called vats ; the vats are set in the ground in such a manner^ as to be as high as the breast above it. As it is important to preserve the heat of the vats^ they must not be placed in the same apartment with the cauldrons^ where a free circu- lation of air is necessary, but in an adjoining one^ constructed in such a manner as to preserve the heat. This place is called giiesdres/^ and the laborers " guesdivns/^ who should be instructed^ by long experience^ to enable them to prevent the accidents to which the vats are subject. Blue can be dyed with pastel^ or woad : it makes a solid blue^ but not deep^ and only a small quantity of color is obtained^ as heretofore mentioned^ Vv hen treating of these substances ; but by mixing it with indigo^ vats very rich in color are prepared, and are almost exclusively used for dyeing wool, and woollen stufis. They are calL ed "])astel vatsP 108 Hellot has Bot designated witli precision the proportions of the substances which are issed in preparing pastel vats. We shall publish from the Memoirs of Quetremere^ a description of a vat of this lund. It is^ nevertheless proper to remark^ that the quantities are varied^ not only in the dif- ferent dje-houses^ but according to the shades which are desired to be obtained. For a vat six feet six inches deep^ and three feet six inches in diameter^ five hundred and sixty pounds of pastel pelots which are first pulverized^ are thrown in. Thirty-five pounds of woad are boiled for three hours^ in a cauldron of water^ suf- ficient to fill the vat. When this decoction is fin- ished^ thirty-five pounds of madder^ a^nd a basket of bran are added ; it is then boiled for half an hour^ when twenty quarts of water are poured in^ and the bath allowed to settle ; the woad is then taken out^ the liquor poured into the vat, which vshould be stirred continually, and for a quarter of an hour after it is filled. All these operations being finished, the vat is covered over ; it is left six hours in this state, af- ter which it is uncovered every three hours^ and stirred for half an hour. When blue streaks are perceived on the sur- face, what is called itsfoot^ or base, (son pied) is given to it, that is to say, nine pounds of quick lime are put in. When this substance is introduced, a change is perceived. The color of the vat becomes of a darker blue, and the exhalations more acrid • Immediately after the lime is put in, or at the same time, the indigo is introduced, after it has been pulverized in a mill^ with a very small quan- 109 tity of water. Wlien it is reduced to a thick paste it is drawn off by a hole in the bottom of the mill^ and thrown into the vat without any other preparation. The quantity of indigo to be put into the vat, is determined by the shade which it is desired to give the cloth or wool. From eleven and a half to thirty four and a half pounds of in- digo^ may be put into a vat of the above dimen- tions. When by stirring the liquor with a rake^ a fine blue frothy called fleuree^ is produced^ it is not necessary to agitate it any more^ except stirring it twice in six hours^ to perfectly mix the materials ; sometimes it is also necessary to add a little lime. The decoction^ when poured upon the pastel^ being boiling hot^ care must be taken not to leave the vat exposed to the air longer than is necessary to stir it. As soon as this operation is finished, the vat is closed^ with a large wooden cover, over which thick rugs are spread, and every means are taken to preserve the heat of the vats, witli« out using fire ; but notwithstanding these precau- tions, the heat cannot be retained but for a limited time ; in about eight or ten hours the heat becomes very feebh?, and will be entirely dissipated if the liquor is not warmed again. This operation consists in drawing off nearly all the liquor from the vat into the cauldron, under which a fire is made. As soon as it is suf- ficiently heated, it is put back into the vat again, and is carefully covered over. The pastel vat'^ is subject to two accidents ; the first takes place when it becomes roide'^ (stiff) or rebutee,^^ (rejected) according to the 10 110 language of the guesdrons this is known^ when a vat is uncovered^ which before presented tine bine streaks or shades^ it appears blacky with- out any blue streaks or froth ; if stirred^ it appears of a deeper blacky and the odour of the liquor^ in- stead of being sweety as when the vat is in a good state^ becomes very acrid. If it is attempted to dye with a vat which presents these characteristics, the stuffs will not take any color, except a dirty grey ; these bad qualities are occasioned by an ex- cess of lime. The " giiesdrons^^ use different means to restore a ^ roid^ vat; some put tartar in it, bran, urine, madder, and others heat the liquor again. Ac- cording to Heilot, the best remedy is to put bran and madder into it ; and if there is not a great excess of limej, it is sufficient to let it remain five or six hours at least, then throw in a quantity of bran, and three or four pounds of madder ; it is then immediately covered over, and after a prop- er time examined. If it is "roid^^ in such a man- ner as only to appear blue when cold, it is best to leave it to restore it^lf, a number of days, without being agitated or stirred. When it be» gins to assume a favorable appearance, the liquor should be again heated ; then the fermentation is generally renewed ; which can be excited with bran and madder, or a basket or two of fresh leaves. Hecquet d'Orval, and Ilibaucoiirt recommend, if the vat is only slightly " roide^^ to merely re- frain from stirring it ; but if the evil has made greater progress, put some pounds of bran, tied op in a bag, into it, and at the same time scatter Ill into it three or four pounds of powdered tartan The bag is taken out^ after the end of five or six hours, and the vat stirred : if the vat is not then restored^ the same pi-ocess must be repeated. Quatremere says^ he has restored a vat that had become roide, from an excess of lime^ by heating the liquor twice^ and leaving it undisturbed for two days J after which it gave the characteristic froth. He left it undisturbed^, sometimes three days^ and then heated it a third time^ which re- stored it. The second accident to which the pastel vat is subject^ is putrefaction. When this happens^ the blue streaks and froth disappear, the color becomes reddish, the sediment at the bottom rises, and a fetid odor is exhaled. The putrefaction is occasioned from too small a quantity of lime being put inio the vat. As soon as it is perceived that putrefaction has com- menced, it should be immediately prevented, by adding lime,^ and stirring the vat ; at the end of two hours, more lime is put in, and the liquor again stirred ; this is repeated until the vat is re- stored, but care must be taken not to carry this process too far. It is to be observed, that a pro- per distribution of lime, demands the greatest at« tention in preparing a 'pastel vat ; the fermenta- tion of pastel and other substances, which tend to disoxygenize indigo, should be moderated ; for if carried too far, the coloring particles are destroy- ed ; but a too great action of the lime impedes the fermentation more than is necessary. It is to be inferred, then, that the excess of lime, without doubt, disappears, by the successive formation 112 carbonic acicl^ or increases the fermentation^ or a part of the lime is saturated with a vegetable acid. Another use of the lime is to hold in solu- tion the coloring particles of indigo and pastel^ which have been disoxygenized. Pastel in pe- lotes^ as well as the leaves^ are made use of. We have seen an able dyer of Rouen use for his vat^ the pastel plant^ simply dried^ and with more ad- vantage than the common woad. The vat is stirred two hours before it is used for dyeing, and to prevent the sediment at the bottom^ called paste^ from producing inequalities in the color^ a kind of net made of large cord is introduced into the vat^ called champagne f ^. the cloths and wool to be died^ are first soaked in warm water ; they are then put into the vat^ where they remain a longer or shorter time^ according to the shade of color which may be desired ; they must be taken out and aired from time to time ; the green color which the liquor communicates^ is changed to biue^ by the action of the air ; it is difficult to dye an equal clear blue color^ in a very rich vat. The best method of obtaining these shades^ is to make use of the vats^ whicli have been already nearly exhausted in dyeing. The wool and stuffs colored blue^ should be washed with great care^ to cleanse them of the coloring particles which do not adhere to them^ and even deep blue cloths should be carefully washed with fuller^s earthy and a little soap^ w hich does not change the color. Those which are intended to be colored black should be treated in the same manner; but this operation is less necessary for those which are to be dyed green. A vat iii which no pastel is introduced is called an indigo vat. The vessel used for this purpose is a cauldron/* v^hich being of a conical form^ a sufficient space for making a fire under it is left between the masonry which surrounds it^ and on which it is supported bj the rim : forty buckets of water are put into the cauldron^ or less^ accord- ing to its size^ seven pounds of tartrite of potash^ as much bran-, fourteen ounces of madder are put into the water^ which is afterwards made to boil ; then seven pounds of indigo^ pulverized in water^ are put into the cauldron^ which is carefully stir^ red^ then covered over ; a little fire is kept up under it, and is stirred every two hours after, until the liquor becomes blue, which happens w ithin forty-eight hours ; if it has been well man^ aged, the liquor will assume a fine green appear- ance, covered with copper colored pellicles and blue jfroth. This vat is much more easy to manage than that of pastel, but as all the blue is derived from indigo, it is more expensive ; alkali, which is used to dissolve the indigo, being more soluble than lime, the dyeing liquor is richer in color. When this vat is in a proper state, dyeing is com- menced, in the same manner as with the pastel vat, Hellot describes two vats in which indigo is dissolved in urine ; vinegar is put into one, and the other tartar and allum ; a pound of each for every pound of indigo : madder is used in botho A large quantity of urine must be used. The dis- solution of the indigo, deprived of its oxigen by * Memoire siir Tlndlgcpar Hecqiiet^rOrval et Ribancoart* *10 114 the urine and the fermentatioE of the madder^, m ill coiisec|ijeiice of the ammonia produced from the urine by the action of the heat and potrefao tion. Hellot remarks that an effervescence took place when the solution of alum and tartar was-'. poured in,, which probably tended to impede the putrefaction ; but these vats are not to be compared to pastel/^ or indigo vats/^ as the process of dyeing with the latter is more rapid^ and the others are only calculated to be used in a small way. When the "indigo vat/^ which has been de- scribed^ is made use of for dying silk ; more indi« go is put into it than the quantity above mention- ed^ but the proportions of bran and madder are very near the same. Macquer^ says^ if a pound and three quarters of madder are put into it^ which is a cjuarter part of the tartrite of^'iotash^ the vat will be of a darker green^ and the color of the silk more permanent^ and not less beautiful. The pastel and other vats which have been mentioned^ are not proper for dyeing silk^ as they do not color €|uick enough. When the vat is in a proper state^ what is calL ed a br^vet/^ is given to it^ which is done by adding two pounds and a quarter of tartrite of potash^ and a quarter of a pound of madder ; it is then stirred^ and four hours after it is fit for dye== Irig. The liquor should then be only blood warm. The silk is' put into the vat after it has been boiL ed Yviih 69 pounds of soap to 230 pounds of silk, and afterwards scoured twice or more in running water. As silk is very subject to take an unequal Art i!e ia Tcifttiire en sole* lis color^ it becomes necessary to dye it in small quantities ; the workmen plunge in each parcel one after another^ afier it has passed over a wooden cylinder, and when each have been turned through the dye several times^ they are wrung out and ex- posed to the air until they turn blue^ when they are thrown into pure water and afterwards passed through the vat several times. Care must be taken that silk which is colored blue is immediately dried ; during winter., aad in damp weather^ it is dried in a room^ heated by a stove. When the vat becomes weak^ and the green color diminishes a brevef^ is given to it^ con« sisting of two ounces of the tartrite of potash^ a little madder, and a handful of bran. When the indigo becomes exhausted^ a proper quantity of the tartrite of potash^ madder and bran must be put into the vat. Some dyers make use of the exhausted vats^ for dyeing light colors^ but the blue which is thus produced^ is not so handsome or permanent^ as from new vats^ in which a less quantity of indigo is introduced. Silk cannot be dyed a deep blue with indigo alone ; therefore it is necessary to prepare it^ by giving it another color as a base ; for the Turkish bliie^ which is the deepest^ the silk is steeped in a very strong bath of sorrel^ and one less strong for royal blue ; it is then put into a new rich vat. Other blues are dyed without a basis. There is dyed a deeper blue than the royal^ which is called fine blue ; for the basis of which cochi- neal is used^ instead of sorrel^ as it makes a more permanent color. 116 Bilk is dyed a toierable good blue with verdi-^ grise and India wood ; its solidity can be aagmeot* ed by first passing it through the dye^, then soak- ing it in a sorrel bath^ and immediately after^ put« ting it into the vat again. In coloring raw silk blue, that which is natur- ally white should be selected, which is first soaked in water, and then passed through the vat in sep« arate parcels, in the same manner silk stuffs are dyed. Raw silk takes the color more easily and with more rapidity, than manufactured. To dye linen and cotton, according to d' Aplig^ ny, a cask is used as the vat which contains very near 125 gallons. The quantity of indigo gener* ally used is six or eight pounds. This indigo, after being pulverized, is steeped in a clear lye, made of an equal quantity of potash and a quan» tiiy of lime, equal to that of indigo. It should be boiled until the indigo is perfectly dissolved in the lye, when the melange should be carefully remov- ed, and great care must be taken that the indigo does not adhere to the bottom and burn. While the indigo is steeping, an equal quanti» ty of quick lime is slacked, and twice as much sulphate of iron is dissolved, and mixed with five gallons of water. When the ingredients are per- fectly dissolved, the liquor is turned into the vat, which should be previously half filled with w^ater; then the solution of indigo is • put in, and the rest of the lye which was not used in steeping the in- digo. Afier all these ingredients are put into the cask, it is filled within two or three inches of the top, with water 5 it is stirred with a rake, two or tliree times each day^ until it is fit for dyeings which happens generally within forty^eight hoiirs^ according to the temperature of the air^ which more or less accelerates the fermentation of the vato Some persons add to a vat^ formed in the preced- ing manner^ a little Jbran madder and pastel.^ At Rouen another process is osed^ which Quat- remere has described. The vats are composed of a species of flint ; the interior and exterior are covered over with a plaister made of a line ce- ment ; they are arranged in parallel lines in the dyeing room. Each vat will hold four hogsheads of water^ and eighteen or twenty-t\to pounds of indigo are put into thern^ which is first steeped eight days in in a caustic lye^ strong enough to bear an egg. The indigo is then pulverized in a mortar^ in which it is generally steeped. The vat is then filled nearly fillip and twenty-three pounds of lime are put into it^ after it is well slacked ; the liquor is stirred^ and forty pounds of the sulphate of iron added. When these ingredients are perfectly dissolved^ the pulverized indigo is sifted in ; the vat is stirred seven or eight times the first day^ and thirty- six hours after is fit for dyeing. The vats should be prepared at different times ; the process of dyeing is commenced by passing the cotton or linen through the vats which are most exhausted^ and continue to pass them from vat to vat, to the strongest^ until the desired shade is produced. The cotton and linen should be wet Proces-verbal des operations de teint faites a Yvetot par Francois Gonin, 118 before it is put into the first vat ; it must not re- main in the liquor more than five or six minutes^ as in that time it takes up all the blue of which it is susceptible. When a vat has been used three or four times^ it begins to change ; when stirred^ either no streaks appear on its surface, or they are black ; it is re- newed by adding four pounds and a half of the sulphate of iron, and two and a quarter of quick lime, and is stirred twice ; a vat can be renewed three or four times, lessening the quantity of the ingredients, in proportion to the diminished strength and quality of the dye. In the vats which have been described, it is the potash and lime which makes the indigo soluble^ being disoxygenized by the precipitate of iron. Lime alone can be used to precipitate the suL phate of lime and dissolve the indigo, which has been deprived of its oxygen ; the solution of indi- go, however, is less condensed, and cotton cannot be colored a deep blue, or at least so soon in this kind of vat, as the preceding ; but this circum- stance is often an advantage ; some persons aug- ment the condensation of tliis vat by adding a lit- tle orpiment and potash. Bergman and Haussman have given particular descriptions of this vat, with some changes in the proportions. The latter remarks, that the suL phate of iron should not contain any copper ; for the oxyd of copper re-establishes the indigo, which it is necessary to keep in a state deprived of its oxygen, until it is combined with the articles intended to be colored. This observation applies to all cases where sulphate of iron is used with in« 119 digo. He further remarks, thai cotton clotlis which are put into water-, acidulated with sulphu=^ ric acid, after being taken from this vat, receive a more beautiful blue, than by washing them in a stream of clear water, or drying them immediately. The following superior method of preparing such a vat, is confirmed by experience, and the different uses to which it is applicable. The proportions for this vat are, one part of in« digo, two of sulphate of iron, and two of lime; after stirring it several hours in succession, until it comes to, it is left, undisturbed, two days, when it is fit for dyeing. Before using it, the froth is taken off. Every night, after the work of the day is finished, the vat is nourished, by boiling, in a small vessel prepared for the purpose, a portion of liquor not so strong as that in the vat, to which is added the froth of the vat, and the next day this is poured into the dyeing vat, which is stir- red, then covered over and left until used again. When the vat becomes weak, lime and sulphate of iron are put into it, to increase its strength. In dyeing linen cloths, they are supported, ex« tended upon frames, by fixing their edges to small hooks set in the horizontal cross pieces of the frames ; the frames are plunged into the vats by means of a pulley. That the cloths may be equally wet, the frames are suspended in such a manner, that the whole length of the cloth is in the vat at the same time ; but care must be taken that the underside of the frame does not touch the sediment at the bottom. After being exposed in the air for a time, to fix the color, the cloths are washed out with care. Bergman describes another vat^ wliicli is very good and convenient for dyeing cotton and iinen^^ and which is also described by 8ch.effer. Take a solution of very strong alkali^ and add six oun- ces of pulverized indigo for each quart of liquor* When the indigo is v^ell mixed with the liqoor^ one pound of powdered orpiment* is put in ; it is then well stirred, and in a few moments the liquor becomes^-green ; a blue froth and. pellicle arises^ when the fire must be extinguished^ and the bath is fit for dyeing. The inhabitants of the island of Corfu prepare and use pastel in a manner totally different from that in use with us^ and which deserves to be de- scribed. M\ Bottaf describes it as follows. The inhab- itants of Corfu pull or cut pastel w^hen it is full grown^ pull oft* the leaves and make no use of the stalks. The leaves are bruised in a mortar or be- tween two stones^ immediately dried in the shade or su% and thus preserved for use. When they wish to dye^ they put this dried matter in a vat, with a quantity of water^ and leave it to ferment ; when a certain degree of heat has taken place, they add at different times lye, slightly charged with alkaline salt ; this lye will injure the cloth if it is too strong. As the fermentation increases^ the mass becomes putrid^ and exhales a fetid and insupportable odor^ when the liquor begins to ap- pear green. At this last state of putrefaction^, the articles to be dyed are put in^ for it is at that mo- * Sulphurized. f Storia naturale e medica dell'isola de Corfu. Milano, an. VIL 2 vol. in-16, vol. 2, p. 116. 12t meiit the dyeing matter is io perfection. Tliey are left in the vat a week^ and take a very deep and solid blue. This is the manner the inhabit- ants of the island of Corfu color their wool and eioths. Ardnino describes thfe same process^ with some modifications^ which we shall mention.^ They put the pastel in a basket^ and water it for eight days^ morning and evenings to soften it and make it ferment. Thev then throw it into a vat. w^here the articles to be dyed have been steeped in a lye made of ashes. The whole is left for two days-, taking care to stir it several times each day. The articles^ w hich are now dyed^ are wrung out and hung np in the sun to dry. They are then put into the vat again^ where they remain two day«^ are again taken out and dried ; this operation is repeated four times more, and in about twelve days acquire a beautiful blue color. Dyeing bine with pastel only^ which was the practise all over Enrope^ before the discoveiy of the new continent^ is preserved not only in the island of Corfu^ but also in several cantons of It- aly. It is mentioned in the Memoirs of the Royal Academy of Turin, vol. 5^ page 15^ that at the present time in many parts of Piedmont^ and par- ticularly at Quiers^ where i;arge quantities of pas- tel are raised, and where arg established several dye houses for coloring w ool^ linen, and cotton cloths. In Tuscany also, part of the cloths manufac« tured in the country, are dyed blue without indigo. ^ Memoire di Osservazioni et di Sperienze, in fol. 1 766^ j).22a 11 122 TS^early all the clothing of the country people are dyed with pastel. Anxious to possess the most positive testimony on this subject^ we wrote M. Targioni Tozzetti^ Economical Professor in Florence^ who has been so good as to transmit us the following statement. I have collected the re- quired information relative to coloring blue with pastel^ without indigo. It is used in Florence^ where it is considered the best dye. Those who use it call themselves Vaggelia^ and the dye is designated by the name of vaggella.^ This dye remains in the cauldron several months^ and even a whole year. It was much more in use formerly than at present. In the time of the Republic^ when every citizen had a profession^ those called vaggellaiy were distinguished. Now indigo is put into tl e vats to expedite the operations^ par- ticularly when they become exhausted. These vats are made by putting pelotes of pas- tel and lime into a cauldron^ where they remain for several months. When they are to be used for dyeing, the liquid is boiled and the heat is preserved as long as it may be necessary. A tri- pod is placed in the bottom of the cauldron to prevent the cloths from touching it. I was told that when the pastel is of a good quality, the dye, which has no indigo in it, is better than that in which it is used ; that the edges of the cloths fade less in washing. Cloths colored without in- digo, are designated by the denomination of in- fernal blue J (turchino inferno.) The cauldron ^ Cemot parait deriver de celui de vati, usile aCoifou pour designer le pastel. Nous avoors dit aiHeurs que ia teinlure au pastel etait passec de i'Orieiil en ltalie« 1^3 in which the dye is prepared^ bears the same name. They emit an ammonical odour. Mc Pnymorin^ who had been for a long time proprietor of one of the besi manufactories of cloths in Languedoc^ says in his work on pastel, that in France, a blue basis is given with pastel alone. The cloths are put in a bath of Campea- chy wood, with sulphate of copper and alum, up- on which a solution of tin is poured. Cloths were dyed in tiiis manner, in 1793, a deep royal blue^ which preserved their color perfectly, al- thougli the dye was not so strong as that made with indigo and pastel. The Chinese color with pastel without any in- digo, by passing the cloths twice through the dye. This industrious people have from time immemo- rial, possessed many processes in the arts, which would be very useful, if they were known to us. They have a process of dyeing not used in Fax- rope, which merits attention. It is contained in the " Me moires Missienaires a la Chine^^^ in quarto, vol. 5, p. 503. riie ancient Chinese authors recommend, as an essential and capital thing, to hold cloths and yarn in the vapor of boiling water, prepared for the purpose, when they are taken out of the dye.^' The alkaline or acidulous vapors, which arise from these baths, tend, without doubl, to fix the colors which otherwise would fade ; also, con^ tribute to £;ive a lustre and brilliancy to them. It is certain that our ancestors colored their cloths a brilliant and solid blue, without the aid of indigo. This fact is shown in several parts of this work. We think it possible to find out the process formerly used, if the writings and ordi- nances upon dyeing, published before indigo was common in Europe, were attentively examined, A knowledge of the drugs which were employed at that time, the different preparations and manip- ulations in use, would probably lead to a discov» ery of the method which was employed in dyeing blue. It is from ihese considerations that we have made some researches, and shall state what we have been able to discover, for the benefit of those who may wish to employ themselves on this -subject. . Tieraventi says, in the second edition of his Miroir universal^^^ ^vmi^A in 1586, page 204^^ that wool is steeped in guede^ or pastel, to dry up the grease naturally attached to it, that the madder may more perfectly adhere to the cloth^ and make it darker colored.'^^ He states lower down, ^' that to make a violet color, it is neces- .^ary to put the cloths into a scarlet dye, after they have been steeped in guede.^^ This author does not speak of dyeing blue ; but it is to be conjec- tured from the above passages, that when they wished to produce this color, they began by dye- ing the cloths with pastel, and then immediately put them into a madder bath, then again into a pastel dye, and thus obtained a good blue color. It is also probable that the cloths were submitted to divers intermediate preparations, such as pass- ing them through a solution of alum, and alkaline iyes, &c. It is also to be seen by the 45th arti- < le of an ancient work, printed in folio, without date, that cloths which were to be colored black, were first twice dipped into a pastel bath. This idea^ verified by a combiaation of experiments; may^ perliaps^ lead to happy results. By aa examination of difterent passages which are to be found in the work of Hene Francais^^ it becomes more probable. " Dye cloth with mad- der, (says the author) that is to say, give the first tincture with it ; it is the base for black, blue, vi» olet, purple, columbine, &c. Orseille answers the same purpose as madder, and is made of pas- tel^ limej potash^ and urine. It is principally used as a basis for silk stufts. It is employed as a base for black, violet, and sometimes for dark blue. This dye answers the same purpose as the others. It appears from the first passage, that madder w^as used in dyeing blue ; secondly, that pastel^ which our author calls orseille dye, was a prep- aration composed of pastel, lime, potash, and urine. Is it not probable that the cloths which were colored blue, were first put into this prepa« ration of pastel, then into one of madder, and that then they were again put into a pastel dye. It is necessary here to remark, that this author also says, that this dye serves as a basis for the color. We find in the same work the following re- marks. " Woollen cloths, or silk, should be thus colored : 1st, they should be well scoured ; they should be washed in a solution of alum, which is the first basis ; 3d, they should be washed, to cleanse them of the alum ; 4th, they should be put into a pastel or orseille bath ; 5th, dye it the intended color.^^ *Essaides Merveilles Je la Nature, etc. Rouen, 3622, in 4 to. m 126 In a regulation of 1547^ it appears^ that in dye=. iiig silk blacky it was first colored with pastel^ then wrung out^ and washed^ again dipped in the pastel dye^ and afterwards wrnng out again^ and a third time put into the pastel dye. The cop- peras and nut galls are prevented from injuring the cloth^ by this process. By another article it appears, that cloths were put into a pastel dye that had been soaked in alum water or madder. It is possible that the same process was followed in dyeing blue. The only drugs which are permitted to be used for dyeing permanent colors, by a decree of the court of the parliament of Paris^ under date of the 7th of September^ 1577^ will serve to indicate such as should be chosen for making experiments in dyeing. The 17th article of this decree com- mences thus : The dyers of good colors shall use the following ingredients^ and no others.^^ For making a good black, pastel of Toulouse and Aiby^ madder, alum, potash, and gaulde ;^ for 8carlet^ red and violet^, pastel and graine de Pro- vence ; for crimson, cochineal ; for red, Brazil v/ood ; for green and yellow, gaiilde. India ^vood, called campeachy, is prohibited by this decree. We found in an old w^ork the following recipe for dyeing with pastel alone. Put in a vessel pas- tel, lime and urine^ and stir them for some time. This composition is preserved, which improves by age, and answers for dyeing stuffs in the ordinary luanner. Eesoda-Cifleola. dyer's weedj or welob, yellow weed*- INFORMATION i;PON THE ART OF EXTRACTING INDIGO FROM THE I.EAYES OF PASTEJL. FtJBLISHED BY ORBTUR OF HIS EXCELLENCY, MONTALIVET, Count of the Empire, Minister of the Interioir, PARIS: 1811. INFORMATION UPON THE ART OF EXTRACTING INDIGO FROM THE ILEAVJES OF FASTEIL. (ISATIS TINCTORIA, LIN,) The culture of pastel^ and its use in dyeings has been long known. The manner of employing this plant has va- ried according to the time and place. But even at tlie commencement of the seventeenth century^ pastel appears to have furnished the most solid^ rich^ and economical blue color. At this epoch^ the discovery of the flocculi of anil^ or indigo of the Indies^ and its importation into Europe^ gave a fatal blov^^ to the use of pas- tel^ and has by degrees annihilated one of the most productive branches of our agricultural in» dustry. The governments which anticipated these fatal effects upon the prosperity of their agriculture^ prohibited the sale and use of indigo^ under very severe penalties. But such were its advantages^ ISO that after having resisted for some years^ they permitted its introduction ; and from that moment the culture of pastel was reduced to an hundredth part of what it had been before. Before this epochs there was prepared in the dioceses of Alby^ Toulouse^ Savaur^ Saint-Pa- poul^ Montauban, and Mirepoix, two hundred thousand bales of pastel^ in pelotes^ weighing two hundred pounds each ; but the cultivation of pas- tel has gradually contracted to a single point in Lauraguais^ where there are now prepared only two thousand bales. Normandy, Pieniont, Tuscany, and Ombrie^ lost this commerce in the same proportion. It is not unnecessary to insert here, the reasons of the preference which commerce has given to the indigo of the Indies, over the pastel of our climates. This arises principally from the great-, er facility with which it can be used ; the indigo of the Indies being separated by previous opera- tions, from all useless matter, presents its pure coloring principle. A pound of indigo is produced by labor, from one hundred pounds of the plants which contained it ; whereas the indigo in pastel, such as is at present for sale, is mixed with the bruised fragments of the plants, which makes it necessary to use a large mass of foreign matter, to produce the effect of a pound of indigo. Therefore the dyers, who made use of pastel, were obliged to fill their vats with a snhsrance which was almost entirely deprived of its col- oring principle ; the process difficulty the color unequal ; and it was necessary to immerse the 1^1 staffs in the vat from twenty to twenty-live times^ to produce a uniform deep blue. Those, on the contrary^ who employed the pure indigo of the Indies^ could dissolve from twenty to thirty pounds in the vat, without making the bath too thick. The cloths were more easily managed in it ; they obtained in a short time the desired shade of color ; they could obtain deeper blues than the former, &c. With such advantages, it is not surprising that the indigo of the Indies obtained the preference over pastel, and that the use of the latter has been successively abandoned. The governments of Europe, instead of prohib- iting the use of a substance evidently superior from its qualities, should have excited researches upon the means of extracting indigo from pastel, and put it, in a pure state, in competition with that of the Indies. They knew^ that the coloring principle of pastel was as beautiful and solid as that of indigo, and it appears that there was but one step more to be made. For two centuries, various attempts have been made, at different times, and in divers places, to extract indigo from pastel. Some satisfactory re- sults were obtained ; but no beneficial effects re- sulted from this commerce, either because the re- searches were not prosecuted with suScient zeal, or because the establishments were formed in Ger- many, where the pastel appears not to contain so much indigo by two thirds, as that of the south of Europe. It belonged to the genius who presides over the destinies of France, to open again this source of 18S prosperity. His decree of July 3cl^ 1810^ was aE appeal to ali the learned ; he promised rewards to those who should discover the means of extracting indigo from pastel^ by an economical process, and the object of his decree has been accomplished. Industry having been every where awakened, excited and encouraged, has successively present- ed results, which at last have been rendered so perfect, that w^e are now sure, we have our na- tional indigo. It is particularly in that part of the country where the culture of pastel formed the principal prosperity of agriculture ; in those places tvhere this product w as celebrated and sought for by all Europe, that this labor has been persevered with the greatest activity and success, JH. Potezaina^ of Rieti, Messrs. Ronques and Limouzm^ of Al- by, have prosecuted their researches with merito- rious perseverance. It now only remains to make known anew and easy process for extracting indigo from pastel, and this is the principal object of this publication. We do not think it necessary to treat upon the culture of pastel, because it is already sufficiently known ; or the w^riiiiigs of Messrs. Piiymaurin^ Hnd de Lasteyrte \ can be consulted on this subject. ^ Notice sur k pas f el. t The work to which this Information is attached. EXTRACTION OF INDIGO FllOM THE LEAVES OF PASTEL. Of all the processes for extracting indigo frora pastel, which have come to our knowledge^ we believe the most simple^ sure^ and economical^ is the following- L Selection of the leaves. The leaves of pastel are cut when they are in their extreme vigor^, before they wither or turn yellow. The most favorable moment for making this Jiarvest^ is when they appear of a slight violet color upon their edges. The leaves should be cut in the least possible time^ and immediately put in fermentation^ to pre- vent them from heating and injuring the indigo. The leaves produce the most indigo when the season has been warm and dry. The extraction of the indigo is much easier when the leaves have been gathered after serene^ fair weather. Leaves which have been touched by the frost are yet capable of furnishing indigo ; but the fer« mentation is more feeble^ and the indigo less abundant. 12 WheB tlie seed of pastel lias been sown m Marcli^ the lirst crop is made in June ; and the ^ rops are continued every twenty or twenty -five *laYs^ according to the season. It is advantageous to leave the pastel roots in the ground two years^ as the first crop the second year can be gathered in March^. and in this man- ner from twelve to fifteen crops can be gathered during the two years. II. Fermentation of the Leaves of FasteL - As the leaves are cut^ they are put into osier The baskets are plunged into water^ to wash the leaves^ and cleanse them of the dust and earth wliicli mav adhere to them. They are immediately emptied into a wooden rat^ and arranged in such a manner as not to be too lightly or too firmly pressed down. Planks are placed over the leaves^ to keep them from rising. The vat should be large enough to contain from two to four hundred pounds of leaves. As mon as the leaves are put in the vat^ enough water is poured upon them^, to cover them two or three inches. Soft w ater should be used^ such as will dissolve soap. When the weather is cool^ it is best to put the water in tiie manufactory^ and not to use it until it is at the temperature of 60 or 70 degrees of Fahreolieit^ by which means a more rapid fer- Bieiitalion is produced. 139 The temperature of the bnildiog in wliicii t\m leaves are fermented^ slioiild be kept as near as possible at sixty degrees. The vat should be prepared in sucli a manner as that the feroieiita- tion should be perfected in the day time, to be able not only tlie better to judge of the degree of fermentation^ and to check it at the proper time^ but for the executing of the ulterior labor^ which cannot be well done during the night. Th-e fermentation is established diiriiig the summer^ in a few hours. It is more or less re-^ iarded^ according to the temperature of tlie place^ and the water of the vat. The water at first becomes yellow. Bubbles arise on the surface^ which at first are white^ but by degrees become of a brassy color^ and lastly blue^ from the contact and action of the air. The water of the bath is slightly dried up^ and smells like something burning. The water becomes more and more colored ; its color becomes of a greenish yellow. The fermentation is completed during the sum- mer in eighteen or twenty hours ; it is slower when the weather is cold^ and lasts several days. In general it can be known when the fermenta-^ tion has arrived at the proper degree ; 1st,, when the liquor assumes a yellow color^ bordering on green ; Sd^ when the bubbles are of various iines^ kc. But the most sure means of ascertaining the proper moment for checking the fermentation^ con^ sists in taking some of the liquor in a glass^ and mixing with it a little lime water. If a deep green 136 color is produced by this mixture, and a large number of flakes, of a deep green color are per- ceived in it, it is to be concluded that the fer- mentation is perfect. It is therefore necessary to examine the liquor every hour, from the mo • nient that bubbles begin to appear, and to check the fermentation when an abundant deep green precipitate is obtained. If the fermentation is continued too long after the appearance of these signs, the indigo is decomposed, a less quantity is obtained, and of a very inferior quality. In general, it is better to check the fermenta- tion too soon than too late. In the first instance, indigo of the very best quality is obtained ; and in case the leaves still contain more, they can be submitted to a second fermentation, following the same process. III. Precipitation of the Indigo. When the fermentation has arrived at the pro* per degree, and the liquor presents the character- istics we have mentioned, a cock placed in the bottom of the vat is opened, and all the liquor drawn off into another vat, capable of holding at least twice as much as the first, and covered over with a cloth, that the liquor may be filtered, and deprived of all the impurities which can be strain- ed from it. Lime water is, by degrees, poured into the li- quor, the melange becomes troubled and changes 137 to a deep green ;^ in this state the indigo is mixed with the yellow matter, is suspended in the liquor and forms numerous flakes which are precipitated by repose. It can be known whether a sufficient quantity of lime water has been poured in, when after hav« ing filtered a little of the liquor and put it in a glass, an addition of lime water does not precipi- tate more flocculi, or change the color of the liquor. The lime water is composed of one part of linie and two hundred parts of water. The lime is slacked in the water, and when it is perfectly di- vided, is left to subside, until the water becomes clear upon the precipitated lime^ and this is called lime water. IV. Separation of the Indigo from the Yellow Matter. » When the admixture of lime water with the fermented liquor has produced a green precipitate which floats in the bath, there is nothing more to do but to separate the indigo. The various au- thors who have written upon pastel, differ in their * M. Rouques made use of another precipitate, which he composed in the following manner; he took eight pounds of quick lime and sprinkled it with a little water; when it was slacked, he mixed it with water in a vat, where it was left to repose, after being violently agitated. At the same time he boiled sixty -four pounds of wood ashes in twelve gallons of water; he afterwards checked the ebullition and left the li- quor to cool. These two liquors, mixed together, formed his precipitate. This quantity was sufficient for 650 pounds of pastel leaves. i^8 methods: 1st. Some violently agitate the liqiioi by means of a shaft^ in the bottom of which are placed ladles^ with a winch in the top^ by which it is rapidly turned in the vat^ until there is per- ceived blue particles of indigo^ well formed^ float- ing in a portion of the liquor^ taken out in a glass or plate. This agitation produces an immense number of bubbles J, which sometimes rise three feet above the liquor^ and assume a beautiful blue color^ from the contact of the air. The froth is carefully taken off ; put into small wooden tubs^ left ex- posed to the air until it assumes a fine blue color^ and then put away to dry. Sometimes the liquor does not require to be agi- tated more than a quarter of an hour. It rarely requires more than two hours. It is often neces- sary to add more lime water to accelerate the pre- cipitation of the indigo. When the agitation has separatedf^ the indigo^ the liquor is left to repose ; the indigo is gradu» ally deposited at the bottom of the vat^ and the liquor becomes clear^ Sd. Another process for separating the indigo from the yellow matter^ consists in leaving the green flocculi which floats in the liquor to settle at the bottom. The moment the precipitation is finished^ the liquor above it is drawn off^ and muriatic or sulphuric acid^ diluted with r^ater^ to two or three degrees of Baumes areometer^ pour- ed on the sediment. Acid should be put into the admixture until it is as sour as good vinegar. As soon as the blue appears^ the mass is agitated to facili- tate the action of the acid in every part ^ water is thep poured in to wash the i!idig;o^ and stirred fo? 1S9 some time^ then left to repose; and when the iudigo has settled at the bottom^ the water is drawn off. The green precipitate^ by the action of the air^ becomes blue^ without the aid of acid ; but the latter method is preferable^ as it cleanses the indi- digo of the lime^ with which it is mixed;, and fe- cilitates the separation of the yellow matter. There is no doubt but that the indigo obtained by the last method is purer and of a better quality than the first. To be sure that all the indigo which the liquor contained has been precipitated^ put some of it in a glass^ and add lime water : if no more green precipitate is formed^ it contains no more indigo ; if^ on the contrary^ treat the liquid in one of the methods above described. It is also possible that by one fermentation^ the leaves have not been deprived of the indigo which they contained ; this often happens when the fermentation has not been continued long enough^ in that case the leaves should be ferment- ed a second time^ in the same manner as the first. The indigo obtained by the second fermentation is of an inferior quality to the first. V. Drying of the Indigo. After all the water is drawn off;, the indigo is put into conical linen filters, lined with blotting paper. The indigo is thus drained and becomes firm. It is then taken out with wooden knives, and put into small wooden tubs, with linen bottoms. 140 These tubs are carried to the drying place, where they are placed upoa sticks fixecl in the wall. The drying place should be shaded and free from currents of air. The temperature of the drying place should be kept at from seventy-five to ninety-five degrees of Fahrenheit. When the indigo has acquired the consistence of a firm paste, it siiould be compressed with wooden knives. After twenty or thirty days, the indigo will have acquired a proper consistence, it is then di- vided into small cakes for sale. It sometimes happens, particularly when the in-^. digo has dried slow, that small worms appear in it. It is necessary to pay attention to this, and take them all out, or they will destroy the indigo. Mote. An experiment of Poteziani ; of Rieti which produced thirteen pounds of indigo, in which was included all the expenses of culture and the extraction, convinced him that indigo could be furnished at 37 cents per pound. M. Poteziani extracted one pound three ounces troy, from a quintal of leaves. M. lioiiques has extracted one pound four ounces. ; Paris ^ March i&th^ 1811, CHAPTAL, BAHDEL, THENARD, GAY-LUSSAC, H. ROARD, Gr. L. TERNAUX.