fcf li: lira 'iiiiilllL 1 jjgnijg 1 ,i ^ *^ *-v^,-^. LIBRARY OF CONGRESS. Uiap. Copyright No UNITED STATES OF AMERICA. 4. '■ K:f '.-'■^ '1^^ / m-:' ;f THE CALORIFIC POWER OF FUELS. A COLLECTION OF AUXILIARY TABLES AND TABLES SHOWING THE HEAT OF COMBUSTION OF FUELS, SOLID, LIQUID AND GASEOUS. TO WHICH IS APPENDED THE REPORT OF THE COMMITTEE ON BOILER TESTS OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS ^DECEMBER, i8gg.) / BY HERMAN POOLE, F.CS., Member of the Society of. Cheinical Industry ; the American Chemical Society , the Am^erican Society o/ Mechanical Engineers ; the American Institute of Mining Engineers : etc., etc. SECOND EDITION, REVISED AND ENLARGED. FIRST THOUSAND. NEW YORK: JOHN WILEY & SONS. London: CHAPMAN & HALL, Limited. 1900. TWO COPIES KECEiViiiJ, Library of Congrot% Ufflce of thf APR 2 11900 Ke^ltUr ef Ctpyrlgktft A^y^, xV-* 61136 Copyright, 1898, 1900, BY HERMAN POOLE. l^ rin and Tresca, Machines a Vapeur. Oesterreichische Zeitschrift fiir Berg- und Hiittenwesen. Peclet, Traite de la Chaleur. Percy's Metallurgy, Fuels. Philosophical Magazine. Pf>lytechnisches Centralblatt. Progressive Age. Proceedings : Alabama Industrial and Scientific Society, " American Gaslight Association. AUTHORITIES CONSULTED. xvii Pnoceedings: American Institute Mining Engineers. American Society of Civil Engineers. " Institute of Mechanical Engineers. " Institution of Civil Engineers. Reports: British Alkali Commission. British Association of Gas Managers. " Bureau of Mines, Canada. " Department of Mines, New South Wales. " Geological Survey, Ohio. " Geological Survey, U. S. " South Lancashire and Cheshire Coal Association on Boiler? and Smoke Prevention, 1869. Revista Minera. Revue Scientifique et Industrielle. Universelle des Mines. Sanitary Engineer. Scheerer, Lehrbuch der Metallurgie. Scheurer-Kestner, Pouvoir Calorifique des Combustibles. Science. Ser, Traite de Physique Industrielle. Stahl und Eisen. Stevens Indicator. Thomsen, Thermo-chemie. Transactions Newcastle Chemical Society. Ure's Dictionary. United States Census Bulletin, 1890. Williams, C. W., Fuel, its Character and Economy. Watt's Dictionary of Chemistry. Witz, Traite theorique et pratique des moteurs a gaz. Wurtz, Dictionnaire de Chimie, Zeitschrift Physikalische Chemie. " des Vereines Deutscher Ingenieure. Zeitung Berg- und Hiittenwesen. CALORIFIC POWER OF FUELS. CHAPTER I. INTRODUCTORY. FUELS. Fuels are those substances containing carbon, or carbon and hydrogen, which are utiHzed for the heat they produce upon union with oxygen. The products of this union, called combustion, are carbonic acid or carbonic acid and water. Many fuels, such as wood, peat, crude petroleum, etc., exist naturally; others, such as coke, charcoal, coal-gas, etc., are formed artificially. The {w€i par excellence to-day is coal. Improvements in transportation allow deliveries at points more and more remote from the mines, and the increasing demand, aided by new and improved machinery, tends to lower the cost. New locations are still being discovered, and the old ones are being worked more thoroughly and completely. A large portion of this book will be devoted to coal, other fuels being treated incidentally; and such treatment is fitting, since it is the study of coal to which the energies of physicists and engineers are still principally devoted in their researches on the calorific power of fuel. For convenience of discussion the fuels will be divided into three general heads: Solid fuels — coal, lignite, peat, coke, charcoal, and wood. 2 CALORIFIC POWER OF FUELS. Liquid fuels — petroleum, shale oils, vegetable and animal oils. Gaseous fuels — coal gas, producer gas, water gas, mixed gas, natural gas. CALORIFIC POWER OR HEAT VALUE. The quantity of heat generated by the combustion of a definite quantity of fuel in oxygen is called the calorific power, heat value, or heat of combustion. The expression calorific power or heat value has a wider signification than heat of combustion. In the popular sense the former terms apply to the measure of an industrial yield as well as to the heat given off by the fuel during its complete combustion. The expression Jieat of combustion, more nearly correct from a scientific point of view, is applied, on the con- trary, only to that quantity of heat generated by the substance when completely burnt; that is to say, when the carbon and hydrogen are completely changed to carbonic acid and water. The unit adopted for these quantities of heat is the Calorie and the British Thermal Unit. The Calorie is the quantity of heat absorbed by the unit of weight of pure water when its temperature is increased one degree Centigrade. This unit is usually one gram or one kilogram. When it represents the atomic or molecular weight, it is called the atomic or molecular calorie^ the gram, being taken as the atomic unity. The British Thermal Unit (B. T. U.) is the quantity of heat absorbed by one unit (usually one pound) when its tem- perature is increased one degree Fahrenheit. It is -^ of a calorie. A kilogram in burning generates n calories with a kilogram as unit and the Centigrade scale; a pound generates n calories, with a pound as unit and the Centigrade scale (W. Kent's pound-calorie); or, whatever the weight taken, there will be generated the same number of calories, using the same unit of. IN TROD UC TOR Y. 5 weight and the Centigrade scale. Hence to pass from the Centigrade scale to the Fahrenheit scale multiply by the factor 1.8, that being the ratio of the two scales- In this work calories referred to the kilogram (kilo- calories) will be used, and the calorie will be the quantity of heat necessary k) raise the temperature of that amount of pure water one degree Centigrade. We will omit consideration of the variations in specific heat of water; to consider these it would be necessary to state that the initial temperature was o° C. But, as remarked by Berthelot, "' the calorie varies only to a very slight degree if we take the water at a slightly increased temperature — at 1 5° or 20°, for example; so that we are accustomed to regard as constant the specific heat absorbed by the water for each degree comprised in this interval of temperature, thus simplifying the calculations." We may lessen this little error by referring the calorie to a litre of water instead of a kilogram, that is, by measuring the water instead of weighing it; the weight of a litre of water diminish- ing from its maximum density at 4° C, while its specific heat gradually increases. The error of calculation is thus made less than the error of experiment. HEAT OF COMBUSTION. When the fuel contains hydrogen, its heat of combustion may be expressed in two ways. Hydrogen in burning pro- duces water, and this water may be either condensed or in the state of vapor. The same number does not apply to both cases, since the vaporization of the water formed consumes heat, which is not given up to the calorimetric bath. We usually consider the heat of combustion, the result of the experiment made under ordinary conditions, or when the water is in the liquid state; this is the general acceptance of the term heat of combustion. Some authors, however, prefer to consider the water as vapor. It is easy, however, to change from one system to the 4 CALORIFIC POWER OF FUELS. other. The heat of combustion of one kilogram of hydrogen being 34500 calories,* and the water formed being liquid at 0° C, a portion of the 34500 calories is used to vaporize the water in the case where it is gaseous or considered as such. Experiment has shown that the heat of vaporization of water is expressed by the formula of Regnault, 606.5 + 0.305/, or 1091.7 -|- o.305(/ — 32°) for Fahrenheit degrees, in which t represents the temperature of the water in the state of vapor. Now one kilogram of hydrogen produces nine kilograms of water. To keep these nine kilograms of water in vapor, at 100° C. for example, there will be needed, by the abov^e formula, 637 calories per kilogram of water, or nine times as much per kilogram of hydrogen, which is 5733 calories. These 5733 calories reduce to 5453 when the water is considered as being at 0° C. instead of at 100° C. Deduct- ing 5453 calories from 34500 calories representing the heat of combustion of hydrogen, the water formed being condensed, we obtain 29047, which number represents the heat of com- bustion of hydrogen, the water being in the state of vapor at o*^. We will call it, in round numbers, 29ioof calories, as is done by several writers. THERMOMETERS. Before taking up the study of calorimeters, we must con- sider the calorimetric thermometer, which is a most important part of the apparatus employed. The reading of the ther- mometer and the corrections are quite delicate and also very important, the calculation of the heat of combustion depend- ing principally on their accuracy. In this work calorimetric questions relating to fuel only will be considered ; hence a description of ordinary ther- *62iooB. T. U. t 52380 B. T. U. INTRODUCTORY, 5 mometers and their manufacture will not be needed. They are usually bought all finished, and should be obtained only from reliable dealers. Favre and Silbermann employed a thermometer of their own design, divided into J^ degrees and graduated from 32^ to 0° C. Each degree occupied about 0.3 inch. By means of a cathetometer they read to yi-g- of a degree. Their calori- metric bath of 2 litres capacity was subjected to at least 8° elevation in temperature, and the quantity of substance necessary to use at times exceeded 2 grams. To lessen this amount of rise in temperature and also the time of combustion, they used longer thermo- meters, with scales reading to -§^^-0° or " Scheurer-Kestner used ^ - 3 J 2 1 — c& even to -^^-^^' a thermometer divided to -5^^° with his Favre and Silbermann calorimeter. Since then they have been used gener- ally. Such thermometers are difficult to work with, and require care in ma- nipulation, and often a series of ther- mometers or at least two with scales in sequence are employed. If the initial temperature of a calorimetric bath is found a little above the highest graduation on the first thermometer, and if the rise in temperature of the bath amounts to two degrees, we must substitute the second one having for its lowest degree the highest of the first. Besides the trouble of substitution, it necessitates a correction for agreement of the degrees common to the two instruments. To obviate this difficulty the ** metastatic " thermometer was invented by Walferdin and described in the Comptes Rendus de T Academie des ScienceSy 1840, p. 292, and 1842, p. 63. Fig. I. — Metastatic Thermometer. O CALORIFIC POWER OF FUELS, As it is not advisable to have the increase of temperature more than three or four degrees, and as this increase must be measured very closely, thermometers are used in which the stem is so drawn out and divided that small fractions of a degree can be easily read. The divisions of the scale should not be greater than J°, and much finer is desirable. Many physicists use special thermometers having the reservoir and the tube near the zero point blown large enough to hold all the mercury needed from o° to 1 6° or to the be- ginning of the divisions. The graduations, engraved on the glass, should then begin and the tube be drawn out so that they may be sufficiently fine. Too long a tube (over i8 inches) is liable to damage. If the mercury cylinder be too large it does not respond quickly enough to minute changes in temperature. Readings of the thermometer are usually made v/ith a cathetometer, and hence -gL-° is sufficiently small. The length of a degree should be at least one inch. With all thermometers it is essential that the glass of the bulb should be rather thin, or the thermometer will be '* too slow." The slightest difference in temperature must be shown immediately by a movement of the mercurial column. To test for sensibility, read the height of the column and then place the hand on the bulb. If sufficiently sensitive the mer- cury will descend quickly from the expansion of the glass and afterwards rise. In thermometers divided to yw° ^^^^^ move- ment should be immediate, and over several hundredths. In ordinary calorimetric experiments the correction due to length of the mercury column flowing out of the bulb may be neglected for several reasons; the experiments should be made in a room where the temperature is nearly the same as that of the calorimetric bath, such correction would be of very little consequence for a slight change of temperature, a,nd the experimenter should plunge the thermometer into the iDath as deep as is necessary to take the reading at che level of the eye. CHAPTER 11. METHODS OF DETERMINING HEAT OF COMBUSTION. There are two methods for determining tne heat of com- Ibustion of substances — one by calculation based on the chemical composition, and the other by actual combustion in a calorimeter. The first method may be considered under two heads: that in which the units are calculated directly from the composition, and that in which they are calculated from the quantity of oxygen consumed during combustion in a crucible. CALCULATION FROM CHEMICAL COMPOSITION. Dulong stated that the heat generated by a fuel during combustion was equal to the sum of the possible heats gener- ated by its component elements, less that portion of the hy- drogen which might form water with the oxygen of the fueL His formula was X = 8080C + 34SOO (h - j), or expressed in B. T. U.'s, X = 14500C + 62 100 ^H — —J, in which X = the heat of combustion sought; 8080 = the heat of combustion of carbon in calories ; 14500 = '' ' '' '' ** *' " " B. T. U. ; 34500= " '* ** ** *' hydrogen in calories; 62100= *' ** '* '* '' " '' B. T. U. ; 7 8 CALORIFIC POWER OF FUELS. H r- = the quantity of hydrogen less that supposed to form^ water with the oxygen. Other authors and experimenters have tried to interpret their results by a general formula with varying success. Many of them by working on a certain number of coals from a certain location work out a formula which applies to that set of coals, but not as well to another set. A few of them will be given. They all resemble Dulong's and are usually only modifications of his original one. The Verein Deutscher Ingenieure adopted the following: X = 8100C + 29000 f H — — j + 2500S — 600^, in which allowance is made for the heat of combustion of sulphur and the heat of the hygroscopic water. All the coefficients are round numbers and that for hydrogen, 29000, is the one in which the water is supposed to be as aqueous vapor, all the water being considered as passing off in that state. None of the other formulae uses this coefficient. It gives rather low results. The question as to the advis- ability of reckoning the heat due to sulphur is a debatable one. In no case does it amount to more than a verv small per cent and can have but little effect on the total. Balling gives as formula X = 8080C + 34462 (h - g) - 652(^ + 9H) to represent the actual occurrences in a steam-boiler fire work- ing under a pressure of steam corresponding to 300° F. Schwackhoefer made the following modification to allow for the correction due to hygroscopic water: X = 8080C + 34500 I H - - - 637B. (H-?) METHODS OF DETERMINING HEAT OF COMBUSTION. 9 Mahler formulated one based on the results of calorimetric determination of the heat of combustion of 44 different kinds of fuel. It is _ 8140C + 34500H — 3 000 (O + N) X ■ — ■ — ! or simplified, X = 111.4C + 375H - 3000; or in B. T. U.'s, ;r = 200. 5C + 675 H — 5400. With the coals he examined he found a very close agree- ment between the results calculated by this formula and those observed. A similar but not equally close concordance was found using the Dulong formula. With wood and lig. nites the difference amounted to 2 per cent. His formula applies also to other substances whose constituents are accu- rately known. Cellulose, the heat of combustion of which according to Berthelot is 4200 calories, by Mahler's formula is 4264. In summing up he says: ** From a scientific point of view, in the present state of our knowledge on the subject, we cannot give a general formula depending strictly on the chemical composition which will give the calorific power of combustibles, substances so complex and varied." Lord and Haas in a paper read before the American Insti- tute of Mining Engineers, Feb. 1897, state that in a series of forty Pennsylvania and Ohio coals they found differences varying from -[- 2.0 to — 1.8 per cent between the calculated and the observed results, and an average difference of — 0.12 per cent. In 1896 Bunte published some analyses and calorimetric tests of gas-cokes, showing a difference of from -|- 0.04 to — 1.2 per cent. lO CALORIFIC POWER OF FUELS. Three elements enter into these cases, the analysis, the <:alculation, and the combustion; all may be erroneous. As the matter stands now the weight of error seems to be on the side of the analysis, as our methods of analysis, especially in water determinations, are not entirely satisfactory; yet it must be confessed that some of the most recent analyses give a basis trom which very close agreement can be calculated. With such fuels as coke, charcoal, or anthracite, having but little volatile matter, the results agree quite well, but with the bituminous coals, asphalts, mineral oils, etc., which are so very complex, the differences are greater.* In these the actual proximate chemical constitution seems to make a differ- ence. It may be safely stated, however, that for ordinary industrial uses, in absence of the possibility of a calorimetric test, and with coals having under 20 per cent of volatile matter, a fairly accurate approximation may be arrived at by calculation. The great inducement that formerly existed in favor of calculated results exists no longer. I refer to the difficulty of making a calorimetric test. These can be made now by means of the modern apparatus, so simple and almost self- regulating that the time consumed is but a small fraction of that needed for an analysis, and the labor and care, hardly anything in comparison. If possible, by all means have a calorimetric test. If not possible, use the best analysis available. CALCULATION FROM QUANTITY OF OXYGEN USED. This is the litharge reduction test. It depends on Welter's formula, which is based on the hypothesis that the heat of combustion is proportional to the quantity of oxygen consumed: N=mP, * Mahler's limit for Dulong's formula is O -|- N > 15. METHODS OF DETERMINING HEAT OF COMBUSTION. II in which A^ is the heat of combustion sought, m is the coeffi- cient previously determined, and P is the weight of oxygen necessary for the combustion of one kilogram of the substance. Giving P the value resulting from the use of the equiva- lents — 16 for oxygen to burn 6 of carbon, and 8 for oxygen ±0 burn i of hydrogen — we have and the general formula becomes N = Zm (- + h) = 26880 (- + h).^ To use this method the combustible is mixed with an excess of litharge and heated in a crucible. The button of lead formed shows the amount of oxygen consumed, and from this is deduced the heat by means of the formula. The heat should be increased very slowly. Mitchell substituted white lead for litharge and claimed to obtain uniform results. This formula was recommended by Berthier, and has been used since by a few others. It. is faulty, as was shown by some of Berthier's own determinations in which contradictory results were obtained. Dr. Ure showed that no uniform re- sults could be obtained using the same materials. Scheurer- Kestner in 1892 showed that the formula not only gave erro- neous results, but actually reversed the relation of combus- tibles. In one case cited the heats actually obtained by a calorimeter were 8813 and 8750, while by the litharge test they were 7547 and 7977. The results were not only low, but reversed the ratio. This method is allowable only in cases where the crudest approximations are desired and where no analyses or calori- metric tests can possibly be made. * Value given by M. Ser. CHAPTER III. CALORIMETRY. Calorimeters for rapid combustion are invariably com- posed of a combustion-chamber and a calorimetric bath, usually a cylinder, surrounding it and containing a known quantity of water, the elevation in temperature of which is measured. The combustion is made in oxygen, pure or diluted. Combustion-chambers are either under a constant pressure, as in the calorimeters of Rumford, Favre and Silbermann, etc. ; or with a constant volume, as in the calorimeters of Andrews, Berthelot, etc. With solids the difference of results obtained under constant volume and constant pressure is so small that we shall not consider it. With gases, however, it is different, and we will state under which conditions the results have been obtained. The first calorimetric experiments date from Lavoisier and Laplace. In 1814 Count Rumford replaced the ice calorim- eter of Lavoisier by an apparatus in which the heat devel- oped during the combustion was absorbed by water. It was some time after, 1858, that Favre and Silbermann discovered the causes of the great errors of their predecessors, and pub- lished methods for correcting some while avoiding others. We owe to them, above all, the observation that, even when supplied with pure oxygen, combustion may be only partial, on account of the formation of combustible gases. They determined that this occurs generally, and gave a method of estimating the unburnt gases, so as to make allowances in the calculation. 12 CALORIMETRY. 1 3 Carbon, which, before their time, had given only 7624 calories to Laplace, 7386 to Clement-Desormes, 7915 to Des- pretz, 7295 to Dulong, and 7678 to Andrews, yielded to F. •& S. 8081 after correction for carbonic oxide in the waste gases. This number has since been increased to 8140 by the latest determinations of Berthelot. Berthelot and Vielle have shown that by using oxygen under pressure complete com- bustion can be attained. INSTALLATION OF APPARATUS. The apparatus should be placed in a room free from sudden changes in temperature and consequently protected from direct sunlight. If it is not entirely protected from solar radiation, the apparatus may be set up on the north side and shaded from the direct midday sun by a screen. The calorimeter cylinder with its accessories, as well as the distilled water used, should remain in the room long enough to acquire its proper temperature. The cylinder should be protected as much as possible from radiation by envelopes which vary according to circumstances. Favre and Silber- mann used a cylinder with a double wall. The external one was filled with water, and between this one and the cylinder proper swan's down was packed. The upper part of the cylinder also had a layer of thick paper covered with down on the under side. Berthelot states that the down is more troublesome than useful, and that it may be omitted with advantage. The space between the cylinder and its envelope forms a layer of air which is an excellent non-conductor. In modern instruments the down is replaced by a thick layer of felt. Berthelot even omits this covering, stating that the great cause of loss of heat was not from radiation, but due to evaporation produced by the agitation of the water in contact with the air. He surrounds his cylinder with a layer of air inside of the envelope of water, and outside of all a layer of felt 0.8 inch thick. By this means external influence is much reduced. 14 CALORIFIC POWER OF FUELS. EVALUATION OF THE CALORIMETf-R IN WATER. Before using a calorimeter its equivalent in water must be determined; that is, we must calculate to what quantity of water it corresponds in terms of specific heat. This is to- be added to the weight of water employed and includes the combustion-chamber, cylinder, and the immersed pieces, thermometer, supports, etc. Below is given an example showing the calculation of the value in water of a Favre and Silbermann's calorimeter: Copper, 1145.651 grams at 0.09516 specific heat = 109.008 grams^ Platinum, 22.810 " "0.0324 " " = 0.706 " Value in water of the chamber and accessories = 109.714 " Thermometer, weight of glass immersed, 12 grams at 0.198 = 2.400 " Mercury, 63 " " 0.332 = 2.070 " Total equivalent of water = 114.184 " which added to the 2 kilograms of water in the bath makes a total of 2 1 14. 184 grams of water. The calorimetric weight for the Berthelot bomb at the College of France in 1888 was 398.7 grams for bomb and accessories. The water value of the calorimeter used by Lord and Haas at the Ohio State University, Columbus, O., was determined as 465 grams. Mahler's apparatus had a water equivalent of 481 grams. Still, it is better to determine this equivalent by actual experiment, as we are not sure of the specific heat of the metal of the bomb, which might, however, be deter- mined by a sample taken from the original block of which it was made. Several methods may be employed for this. When we use the calorimetric bomb, we burn in the obus^ using 2000 grams of water, a known quantity of a substance of fixed composition, and of which the heat of combustion, is known, as sugar, or naphthalin. We then use less water and burn a smaller quantity of the substance. If I gram of substance was taken the first time, we may take 0.8 gram with 1800 grams of water the second time. We then have two CALORJMETRY. 15 equations, rrom which we eliminate the heat of combustion of the substance and deduce thence the value in water of the cylinder, etc. This method, suggested by Berthelot, may be replaced by the following, to which he gives the preference: Pour into the calorimeter a certain quantity of warm water, at 60° C. for instance. This water is previously con- tained in a bottle, and the temperature is measured by a thermometer placed inside. As control, operate first without the bomb in the cylinder and afterwards with it in place. One test of this kind gave Berthelot a value of 354 calories for the bomb. The value deduced by calculation from specific heat was 355.4. Below is the detailed calculation giving the separate parts of the bomb. Soft steel. Platinum. Brass. Names of the Different Parts. Weight in Grams. Value in Water. Weight in Grams. Value in Water. Weight in Grams. Value in Water. Crucible 1709.7 221.2 II. 7 187.61 24.28 1.28 728.8 528.8 23.63 17.15 20.0 3.97 108.9 St/->n-rort . I 86 Cone-screw and socket of fi rp-ra rri fr . 0.37 Movable accessoriesserv. ing for suspension and IfinHlincT 33-0 1.07 Screw of bomb 802.7 88.08 10.13 Totals • . • 2745.3 301.24 1290.6 41.85 132.9 12.36 Recapitulation. Metals Used. Steel Platinum Brass (calorimeter and agitator omitted). Weight of bomb Value in water by direct test. Weight in Grams. 2745.3 1290.6 132.9 4168.8 Calculated Value in Water. 30T.24 41. 85 12.36 355-45 354-7 1 6 CALORIFIC POWER OF FUELS. CORRECTIONS FOR THE READINGS. The corrections to be applied to thermometric readings, besides those due to the thermometer itself, are of various kinds, and naturally vary with the kind of calorimeter used. Some, however, are comiiioii to all. The correction relative to heating and cooling concerns all calorimeters. Favre and Silbermann made this correction with a coefficient previously determined, once for all, by a series of experiments. For example, the coefificient that they found for their calorimeter (± 0.0020225) represents the influence of the external temperature through the envelopes and pack- ings for one minute and one degree. Instead of a coefficient of correction thus determined, use preferably a system of correction devised by Regnault and Pfaundler. This system is superior to the preceding, as it allows consideration of all external conditions at the time of the experiment. It is evident, for example, that the evapora- tion of a liquid may vary in such proportions that a fixed coefificient will not always represent it. The system of Regnault and Pfaundler does not need previous experiments nor a determined coefificient. It rests on observation of the thermometer immersed in the bath a Tew minutes before and after the experiment, or at the times when external influence is at its minimum or maximum. Knowing the value of these two kinds of influence, it is easy to calculate it for the whole duration of the test. It is well to continue the observations before combustion for some five minutes. These five minutes should be pre- ceded by at least ten minutes' immersion of the combustion chamber with agitator, so as to establish equilibrium of tem- perature between the cylinder and the water. Suppose the initial correction corresponding to the first period to be zero — which is rare, it is true, but simplifies the CALORIMETRY. 17 demonstration — and that the observations have given the fol- lowing data: Initial temperature of bath 18.460° After I minute 19.700 '* 2 "■ 20.540 ** 3 *' 20.670 ** 4 '' 20.680 *' 5 '' 20.676 '' 6 ** 20.665 *' 7 ** 20.655 " 8 " 20.640 *' 9 " 20.630 * 10 *' 20.620 The combustion once commenced is continued till after the fourth minute and ends between the fourth and fifth minutes, but the equilibrium of temperature between the bath and the combustion-chamber is not established until the eighth minute, the time when the variation due to difference between them has become regular (0.010° per minute). A table of corrections is formed as follows: ■e 18.460° 1st minute. ... 19.700 Mean 19.080° Difference 0.620' 2d - . ... 20.540 20. 120 1.660 3d '^ .., 20.670 20.605 2.14s 4th '' ... 20.680 20.675 2.215 5th - 20.676 20.678 2.218 6th '^ 20.665 7th - ... 20.655 8th '' 20.640 9th " . ... 20.630 joth " 20.620 1 8 CALORIFIC POWER OF FUELS. The total elevation of temperature is 20.676 — 18.460 = 2.216°, and the correction is 20.676 — 20.620 = 0.056° for five minutes, or o.oi 1° for one minute. Then 2.216 : 0.01 1 = 0.620 : 0.0031 2.216 : o.oii = 1.660 : 0.0083 2.216 : O.OII = 2.145 • 0.0107 2.216 : O.OII = 2.215 • o.oiio 2.216 : O.OII = 2.218 : O.OIIO Total 0.0441 There is then 0.0441"^ to be added to the difference, 2.2 16°, increasing it to 2.260°, which is the corrected difference of the bath temperature, from which the heat of combustion of the substance burnt in the calorimeter is calculated. Regnault and Pfaundler's formula is Atn — Ato + K{tn — to) ; in which Atn = ascertained variation of temperature from the heat- ing and cooling of the calorimeter for one minute; Ato = variation at the beginning; tn — to = loss or gain during the total time of the test; n = number of minutes of test. Using the above numbers, K = ^ = 0.00496. 2.216 ^^ CA L ORIME TRY. 1 9 It will suffice, then, to find the total loss or gain to take the sum of all the gains or losses calculated by means of the coefficient K during the whole time of the experiment. Thus, 0.620 X 0.00496 = 0.0031°, 1.660 X 0.00496 = 0.0083°, and so on. For the full and exact method of correction devised by Pfaundler, see vol. ix., p. 113 et seq, of the Annalen der Chemie und Physik. CHAPTER IV. CALORIMETERS WITH CONSTANT PRESSURE. The first calorimeters were of constant pressure; that is, the combustion was carried on at the atmospheric pressure or very near it, and did not vary from the beginning to the end of the experiment. Hence the modifications in the volume of the gases before and after combustion exercised no influ- ence on the observed results. Rumford, in 1814, was the first who tried to correct external influences. He employed a practical method which has often been used since, and consists in giving the calo- rimeter bath a temperature in the beginning of the test less than that of the room, and allowing it at the close to attain a temperature in the same proportion above that of the room. His calorimetric apparatus was composed of a copper boiler of several litres capacity, heated by an interior tube through which passed the gaseous products of the combustion. The combustible was burnt in a little burner placed under the boiler, and the air used circulated around the heater before passing to the burner, thus preventing any loss of caloric by radiation. ' Dulong in 1838 used oxygen, and obtained much superior results. His calorimeter consisted of a rectangular copper box, 25 centimetres (about 10 inches) deep, 7.5 centimetres (2.9 inches) wide, and 10 centimetres (3.9 inches) long. It was closed at the upper part by a cover with a mercury seal. FAVRE AND SILBERMANN'S CALORIMETER. 21 The oxygen passed into the calorimeter by a copper tube opening at one of the sides of the box near the bottom. The gases of combustion were drawn into a gas-holder. The apparatus was enclosed in another likewise rectangular, in which was put 1 1 litres (gf quarts) of water. This was the calorimetric cylinder. The water was kept in motion by an agitator. The unit chosen by Dulong was one gram of water whose temperature was raised one degree. He corrected the tem- perature observed, same as Rumford, but he also noticed that this correction was correct only when the first period was equal to the second. The results obtained by Dulong in 1838 were not published till after his death, in 1843. For hydrogen and carbonic oxide they are but slightly different from the most modern determinations. CALORIMETER OF FAVRE AND SILBERMANN. In 1852 Favre and Silbermann published their first researches on the quantities of heat generated by chemical action and described their calorimeter. All rapid-combustion calorimeters and all with constant pressure intended for solid bodies are copied more or less after that of Favre and Silbermann. The principle and mode of execution in their general lines are the same; the form in some details or the material employed for the combustion-chamber has been modified more or less; but the general apparatus and accessories, as well as the method, have remained as F. & S. left them. We will describe, then, this calorimeter in its details, and outline the modifications made by other experimenters. The calorimeter called Favre and Silbermann's is composed of three concentric copper cylinders (Fig. 2, B, C, D), Cylinder B is the calorimeter cylinder; it is silver-plated and polished on the inner surface so as to lessen its emitting power; its capacity is a little over 2 litres (3 J pints), being 20 22 CALORIFIC POWER OF FUELS. centimetres (about 8 inches) high and 12 centimetres (4} inches) in diameter. In the middle is placed the combustion- chamber A (Figs. 2 and 3). Fig. 2. Fig. 3. Favre and Silbermann Calorimeter. The combustion-chamber is of burnished gilt copper, and is shown in Fig. 3. It is a slightly conical vessel, the large opening in which receives a stopper from which is suspended the burner made of a material suitable to that of the sub- stance operated on. The stopper itself carries two tubes, m and n, the first being an observation tube for the combustion, and is surmounted by a mirror M, which allows examination during the burning. The mirror receives light by the tube m, which is closed by an athermanous system of quartz, alum, and glass. The 'other tube, n, carries the jet for the oxygen. Tube b is closed, or removed during the test with coal, as it is of no use then. Tube c serves as the exit for the waste gases of the combustion, which pass through the coil cc (Fig. 2) before reaching the analytical apparatus. This coil FAVRE AND SlLBERMANN'S CALORIMETER 23 is sufficient to cool the gas to the temperature of the bath. Experimenters should solder the oxygen-jet to the stopper so as to diminish the number of openings. It is also advan- tageous to solder the coil to the cover. Certain fuels with very smoky flames require the addition of oxygen very near their surfaces. Scheurer- Kestner and Meunier-Dollfus employed the following arrangement (Fig. 4), a being the platinum capsule; cc' , the platinum tube, which at the part c fits tight in the mouth of the oxygen-jet; b, b, b, platinum suspen- sion-rods; dj fuel. It is impossible to prevent the genera- tion of more or less hydrocarbons and car- bonic oxide. The weight of the hydrogen and carbon is determined by causing the gaseous products of combustion to pass through an organic analysis tube, after re- moving the water and carbonic acid. For this purpose the exit-tube c (Fig. 3) is con- nected by a caoutchouc tube with a Liebig apparatus, fol- lowed by a U-tube of soda-lime. , The gas-current being rather rapid, an absorption appa- ratus must be used, large and powerful enough to completely free the gas from the carbonic acid and water before it reaches the red-hot copper oxide. This is done by passing the gases through another U-tube smaller than the preceding, and whose weight should vary only a few milligrams. The gases thus freed pass to the tube of hot copper oxide, where the com- bustible gases are burnt to water and carbonic acid, which are collected and weighed as usual. Scheurer-Kestner and Meunier-Dollfus employed a plati- num combustion-tube, and prefer soda-lime as absorbent for the water after the conclusive experiments by Mulder.* Zeitschrift fiir analytische Chemie, I. 4. 24 CALORIFIC POWER OF lUELS. The coal for the experiment must be m pieces; if \n powder, the combustion is more difficult, unburnt gases escaping in considerable quantities, so that it is rare to obtain a complete combustion, and the cinders almost invariably contain small quantities of coke. To determine these, the capsule and tube are withdrawn from the combustion-cham- ber, dried, and weighed. The coke and the little soot on the sides of the capsule are burnt off by calcination in the air and a new weighing made, giving the weight of the carbon and cinder — elements which must be considered in the corrections. From half a gram to a gram of coal may be used. When the combustion-chamber containing the weighed substance is put into the calorimeter all the parts of the apparatus are connected by caoutchouc joints and tested. A slow current of oxygen * from a gas-holder is passed through the apparatus. The combustible is ignited by a few milligrams of burning charcoal, the joint in the tube being broken for the moment, and immediately reconnected without stopping the flow of oxygen. The little glass M allows inspec- tion of the combustion, the intensity of which can be regulated by the flow of oxygen from the gas-holder. The temperature shown by the thermometer is recorded each minute to obtain the data necessary for the correction spoken of above (pages \^ et seq.). To calculate the heat-units developed by the combustion the following elements are needed : 1. Weight of the combustible used; 2. Weight of the carbon remaining in the cinders unburnt or as black ; 3. Weight of the cinders; 4. Weight of hydrogen escaped unburnt; * To prepare the oxygen a copper flask of one litre capacity is used, in ^whicli is placed some chlorate of potash, which is then heated by a gas flame. The gaseous current is very regular, except towards the end, when it may become tumultuous. The addition of a sriiall percentage of black oxide of manganese promotes the regularity of the gas generation. FAVRE AND SILBERMANN'S CALORIMETER. 2$ 5. Weight of carbon escaped unburnt in the gaseous products; 6. Elevation of temperature of calorimeter bath; 7. Correction for heating and cooling caused by external influences on the calorimeter cylinder. The combustion of the coal by this means is rarely com- plete; there remain variable quantities of coke mixed with the cinders formed. An uncertainty attends the calorimetric value according as the combustion was slow or rapid, since this small quantity of coke contains more or less hydrocarbons. These differences, however, apply within very close limits, so that no fear need be entertained of large errors therefrom. When a coal, in pieces, has been burnt, there remains in the capsule only a few milligrams of coke or unburnt carbon. From this we calculate the calorimetric value, using 8080 as coefficient (heat of combustion of charcoal according to Favre and Silbermann); and in using that coefficient the hydrogen which may exist in the coke is naturally neglected, but this cannot be prevented. The carbon and hydrogen of the com- bustible gases which escaped combustion are transformed into' water and carbonic acid, and weighed as such. The hydrogen is calculated as in the free state (coefficient 34500) and the carbon as carbonic oxide (coefficient 2435). It is evident that these are only approximations, since the hydrogen is not disengaged in a free state, but as a hydro- carbon; and its coefficient (34500) should be diminished by the heat of formation of this compound, or, in other words, by the heat of combustion of hydrogen and carbon. This correction, however, is not possible; for neither the composition nor state of molecular condensation of such hydrocarbon is known. Similarly for the carbon, and its heat of combination in the carbon compound. There are, then, some uncertainties, but not of much importance, in the determination of the heat of combustion of fuels — uncertainties which the use of the calorimetric bomb has entirely avoided. 26 CALORIFIC POWER OF FUELS. A complete test will now be described, giving all the cor- rections. Suppose one gram of dried coal in fragments is used. After combustion in the calorimeter, weigh the capsule con- taining the cinders. Cinders after combustion , o. i lo gram. *' " calcination in the air o. lOO " Unburnt carbon remaining in cinders.... o.oio "■ Then Coal used, dried at ioo° C i .000 gram. Cinders o. 100 ' ' Pure coal (cinders out).. 0.900 *' Carbon not burnt during the experiment., o.oio ** There was collected from the combustion of the hydro- carbons and the carbonic oxide o. 10 gram of carbonic acid, corresponding to 0.006 of carbonic oxide (molecular ratio II :7); also o.oio gram of water, corresponding to o.ooii gram hydrogen (molecular ratio 9 : i). Increase of temperature of the bath 3-702* Correction 0.020 Total increase 3. 722" Calorimeter equiv. in water 2. T14 kilos * and 3.722 X 2. 114 =7.8683 Unburnt carbon o.oio X 8.080 cal. = 0.0808 Carbonic oxide 0.006 X 2.403 " = 0.0144 Hydrogen o.ooii X 34.500 " = 0.0383 Total calories from 0.900 gram coal completely burnt = 8.0018 I gram pure coal = 8.891 calories, I kilogram pure coal = 8891 calories, or I pound " " = 16003.8 B.T.U. * 2000 grams of water -|- 114 grams for value in water of calorimeter and accessories. FA VRE A ND SILBERMA NN ' S CAL ORIME TER. 27 In this example the corrections are not very important, since they do not exceed one-half per cent. These are the -ordinary conditions when the coal used is in pieces. With pulverized coal, on the contrary, the quantity of unburnt carbon and of combustible gases increases considerably and renders results less certain. The oppor- tunity we have to weigh the cinders of each test obviates pulverization of the coal to obtain an average sample of the cinders. Favre and Silbermann's calorimeter has been modified by Berthelot in several par- ticulars."^ He has happily modified the agitator and given it a coiled form, as shown in Fig. 5, a detailed description of which is given in his Essai de Me'canique Chimique, p. 14$. This agitator has the advantage over the old one of more completely mixing the water, with less force, and without accelerating evaporation. Fig. 5 shows it placed in the middle of the calorimeter. He has also replaced the gold-plated copper combustion- chamber by the glass apparatus which Alexejew used for combustibles. Fig. 5. * The F. & S. calorimeter with all accessories and an agitator (not me- chanical) costs about 500 francs ($100.00); with mechanical agitator arranged for a laboratory turbine or dynamo the cost is about 600 francs ($120.00). Berthelot's calorimetric bomb of platinum, enamelled inside and not double, costs no more, and is much preferable. A single operator can handle it, while the F. & S. apparatus requires two. Nevertheless, the manner of working the F. & S. calorimeter is de- scribed in detail, because its use fs surrounded by conditions easily realized in all countries. The calorimetric bomb requires oxygen compressed to 25 atmospheres, which cannot be obtained everywhere. 28 CALORIFIC POWER OF FUELS. ALEXEJEW'S CALORIMETER. The apparatus used by Alexejew was composed of a glass combustion-chamber A (Fig. 6), in which he burnt the coal previously reduced to fragments. These fragments were placed on a platinum grating in the centre of the chamber. The fuel was kindled by means of a platinum sponge placed over it, on which impinged a jet of hydrogen from the gas- holder M^ opening at <:, correction for which is of course made in the calculation. The grating contain- ing the fuel was suspended from the glass rod a. As soon as the combustion was started the current of hydrogen was cut off by the cock /, and the oxygen allowed to flow in through by the waste gases pass- ing out through the coil. If the combustion was interrupted, it was rekindled by the hydrogen and platinum sponge. The hydrogen used was calculated in grams and multiplied by 34500. The number of calories thus ob- tained was deducted from that calculated from the rise in temperature of the bath. According to Alexejew, the im- portance of this correction never exceeded one-half per cent, and he never had to rekindle the fuel. Alexejew did not determine the unburnt gases, as experi- ence showed they never exceeded 0.35 per cent. It is im- possible, however, to determine the hydrogen of the hydro- carbons if desired, as these would be mixed with the hydrogen used for kindling, part of which may escape combustion. The kindling with hydrogen might, however, be replaced by that with carbon, as in the F. & S. apparatus. Fig. 6. — Alexejew Calorim- eter. A LEXEJE fV'S CAL OKI ME TER. 29 The calorimeter contained 2500 grams (5.5 11 lbs. of water, a quantity somewhat larger than that usually employed, and which is based on the sensibiHty of the thermometer. To attain the same degree of precision it was necessary to use larger samples of fuel or else have more delicate thermometers. The water was kept in motion by the coil-agitator. The following determination of the calorific value of capryl alcohol will show the use of this calorimeter. Weigh the fuel container before and after the combustion to determine the weight of substance used. If very volatile a portion may be carried along by the gases and condense in the accessory apparatus. Data. Weight of Absorption Apparatus. Calcium chloride tube \ 43-9285 (43.8383 H,0 , 0.0902 Geissler apparatus 3 /3o/2/ (71-7558 CO, 1. 8169 Soda-lime tube i 85.7280 (85.7209 CO, 0.0071 Burner \ ^'''^\ \ 1-4378 Substance burnt o.6jJi Second calcium chloride tube J 9 -334 j 96.3272 H,0 , . . . .0070 Second Soda-lime tube -S 9 • 9 5 (91.0872 .0053 2(^a CALORIFIC POWER OF FUELS. Thermometer Readings. Readin gs taken every minute. 17.500 18.400 20.36a .500 .800 .352 .498 19.200 •342 .495 .500 .332 .494 20.000 .324 .492 .250 .314 .492 .320 .304 .490 .352 .368 .294 17.488 = T .380 .282 20.380 .272 Combustion begins ( Combustion ends. .262 17.690 20.380 = Ti .250 .240 18.020 20.370 20.230 Calculation of Results. Substance burnt ; by weight .0.6773 << < < Terence )rrection '' CO, .0.6758 Dif . .001 K Cc for Cooling. A = 0°.i04. ' •^'^* J T, = 20.484 T = 17.488 i I T^ — T = 2.996 The water and metal parts have a value of 2167.679 grams. i^^ = 6494.367 Cal. 2.990 Corrections. By observation, the loss of heat from water absorbed in the CaCl tubes (0.0454 gram) was 28.1 calories. The loss from hydrogen in the unburnt gases was 25.6 calories, and the loss from carbon in the same 7.9 calories. FISCHER'S CALORIMETER, 2i)b Then grams of substance. 6494.4 28.1 25.6 7.9 6556.0 calories obtained from 6758 The calorific value is then 6556^ 6758 9705. FISCHER S CALORIMETER. Fischer made a combustion-chamber of silver 0.940 fine, so that it would be less easily attacked by sulphur, from which the gaseous pro- ducts of coal are rarely free. He drew off the waste gases at the bottom of the apparatus (Fig. 7), thus avoiding the in- convenience of exit-tubes in the cover of the combustion-chamber. The cool- ling coil was replaced by a flattened pipe of a certain size. A represents the combustion-chamber. The oxygen, purified by passing over potash and then dried, arrived by the tube a fast- ened in the tube of the cover by a caoutchouc joint, and passed by means of the platinum tube r into a crucible z of the same metal, containing one gram of the fuel. The crucible was covered by a grating, which became red-hot towards the end of the opera- tion. This was intended to burn the waste gases, and the black deposited at the beginning. The gases flowed out at /, and after having encircled the outside Fig. 7. — Fischer's Cal ORIMETER. 3P CALORIFIC POWER OF FUELS. of the crucible escaped at b. The thermometer / showed whether the temperature of the gases was the same as that of the bath. The calorimetric bath contained 1500 grams (3.3 lbs,) of water, and was protected against external influences by a wood casing, while the space C was filled with glass wool; but this is not necessary. ;z is a brass cover which may be dispensed with. The thermometer T is the calorimetric thermometer; in is an agitator moved by the string 0. The value in water of the one used by Fischer was 11 3. 5 calories. The coal was dried in nitrogen. The carbonic acid and the unburnt carbon were determined. thomsen's calorimeter. This calorimeter was designed especially for tests of gases and vapors. It is not adapted to tests of solid fuels. It consisted (Fig. 8) of a calorimetric bath of thin brass, with a capacity of some 3 litres (195 cubic inches), protected from radiation by a cylin- drical ebonite envelope ; and a plati- num balloon of half a litre (32.5 cubic inches) capacity, in which the gases were burnt, being delivered through the opening at the bottom. The waste gases passed off through a coil, and a mechanical agitator kept the water in circula- tion. The dried gas was delivered with perfect regularity from a mercury gas-holder, sufficient air or oxygen being added to render it free-burning, and enough oxygen was supplied to insure perfect combustion. This he attained by always having 40 to 50 per cent in the Fig. 8. — Thomsen Calo- rimeter. CARPENTER'S CALORIMETER. 3 I waste gases. The gases passed off through a carbonic acid absorbing apparatus. To reduce to the minimum, or entirely suppress, the cor- rection for temperature he regulated his gas-flow so that the temperature was as much higher than the air at the close of the experiment as it was lower at the beginning. This he easily did by means of his hydrogen supply. If a liquid was tested, it was vaporized and burnt in a specially devised burner which allowed complete combustion of almost all com- pounds not having too high a boiling-point. If too high for heat vaporization, they were carried along by a current of air, oxygen, or hydrogen, as seemed best adapted. The water of the calorimeter being weighed, the lower portion was closed with a rubber stopper and by means of an aspirator a pressure of 8 to 12 inches of water was put on the apparatus to test the joints. When ready, the temperature of the bath and the air was noted for some minutes, the gas- holder reading taken, the burner placed in position, and the test commenced. The depression produced by the aspirator was about 0.4 inch during the whole test. The regularity of the working was shown by a gauge registering the pressure. When the temperature had reached the desired point the gas and electric current were shut off, the burner removed, and the opening closed again. The aspirator was used to draw dry air, freed from CO^ , through the apparatus to insure removal of all waste gases. The apparatus was then allowed to rest, taking the temperature at short intervals for fifteen minutes. He then had all the data required. carpenter's calorimeter. Prof. R. C. Carpenter devised a calorimeter especially for coal determinations, which is a modification or extension of Thomsen's. He has used it considerably in connection with work he has been engaged on, and the results credited to him in the tables at the end of the book were obtained with it. 32 CALORIFIC POWER OF FUELS. Fig. 9 is a sectional view of his apparatus. It consists of a combustion-cylinder, 15, with a removable bottom, 17,. A LJ= JMB^JL I Fig. 9. — Carpenter Calorimeter. through which passes the tube, 23, to supply oxygen, and alsa the wires, 26 and 27, to furnish electricity for the igniter. It also supports the asbestos combustion-dishes, 22, used for CARPENTER'S CALORIMETER, 33 holding the fuel. At its top is a silver mirror, 38, to deflect the heat. The plug is made of alternate layers of asbestos and vulcanite. The products of combustion pass off through the spiral tube, 28, 29, 30, 31, which is connected with the small chamber, 39, attached to the outer case of the instru- ment. This chamber has a pressure-gauge, 40, and a small pinhole outlet, 41. Outside the chamber is the calorimetric bath, I, which is connected with an open glass gauge, 9, 10. Above the water is a diaphragm, 12, used to adjust the level. The calorimeter has an outer nickel-plated case, polished on the inside. The bath holds about 5 pounds of water, and uses about 2 grams of coal at a time. It is thus considerably larger than the bomb, and the charge being larger the time consumed by the test is longer, being some ten minutes for each gram burnt. The entire outside dimensions of the case are 9J inches high and 6 inches diameter. In using the apparatus the coal is ground to a powder in a mill or mortar. The asbestos cup is heated to burn off ail organic matter and weighed. The sample is then placed in it, and the whole weighed again. This gives the weight of the coal used. Place it in the combustion-chamber, raise the platinum igniting wire above the coal, make the connections with the battery, and as soon as the heat generated causes the water to rise in the glass tube turn on the oxygen, and by pulling down the wires kindle the coal. At this instant the reading on the glass scale must be taken. By means of the glasses 33, 34, and 36 watch the progress of the combustion, and as soon as finished take the scale-reading and the time. The difference between this scale-reading and the one previously made is the '* actual " scale-reading. To correct for radiation, allow the apparatus to stand with the oxygen shut off for a length of time equal to that of the combustion, and take the scale-reading and the time. The 34 CALORIFIC POWER OF FUELS, difference between this and the '' actual'* reading is to be added to the ** actual " for the " corrected ** reading. Now, by inspection of the calibration-curve previously- prepared, at the point corresponding to the corrected scale- reading will be found the B. T. U.'s for the quantity burnt. The ash is determined by weighing the asbestos cup after the combustion. The following shows all the calculation needed: Weight of crucible (asbestos cup) .... i .269 grams. '* *' '* and coal 3-Oi7 " ash 1.567 '' '' *' combustibles 1.450 *' "■ " ash 0.297 " " " coal 1.747 ** 1.747 grams X 0.002205 = 0.003852 pounds. First scale-reading 3.90 inches; time 2 hrs. 55 m. Second" " 14.70 " " 3 '' 20'' Third " '' 14.30 " " 3 " 45 " ''Actual" scale-reading. 14.70— 3.90= 10.80 inches. Radiation correction 14.70— 14.30= .40 " Corrected reading 11.20 *' On the calibration-sheet 11.2 corresponds to 46.25 B. T. U.'s, and 46.25 B. T. U. -^ 0.003852 = 12000 B. T. U. per pound. All air must be removed from the water in the bath, the apparatus must work at a constant pressure, and the pressure for which it is calibrated. A pressure of 10 inches of water has been found satisfactory. Complete combustion is always attained in the asbestos cups. It will be seen that the use of thermometers is obviated, and also all corrections but one. The apparatus is intended S CH WA CKHOFER S CALOR I ME TER, 35 for ordinary every-day work, and will give good comparative results when used according to directions, which must be implicitly followed. The amount of calculation is reduced to a minimum, and there are no delicate parts requiring extra care and adjustment. For the purpose intended, it seems an advance over the others previously used, which could never give more faint approximations to correct results. schwackhofer's calorimeter. In 1884 Schwackhofer published calorimetric researches on different kinds of coal, using a calorimeter in which he rnade Fig. 10. — Schwackhofer Calorimeter. several modifications intended to render it specially applicable to such fuel. He considered it advisable to use as much as five or six grams of coal, which is six times that generally used. He burnt at the same time and under definite conditions, shown 3^ CALORIFIC POWER OF FUELS. in the sketch (Fig. lo), a certain quantity of sugar-charcoal, the combustion of which was intended to accelerate and com- plete that of the coal tested. In the figure (Fig. \6)ab represents the combustion-cham- ber, c the calorimetric bath. Minor details of accessories, en- velopes, regulators, etc., are omitted. The burner proper is of platinum and of two pieces, a and b, superimposed, the coal being placed in the lower portion, the sugar-charcoal in the upper one. All pieces of the burner may be removed for the introduction of the coal and for cleaning. The two combus- tibles rest on perforated plates of platinum, in which the per- forations, made by a special machine, are so small that light can hardly pass through, and from which the cinders can be completely removed ; the holes in the upper one are slightly larger than those of the lower. The oxygen enters through three tubes, e, f, g. Tubes g and in pass outside the bath, and carry mirrors to allow inspection during the burning. The waste gases pass off at the bottom through a coil n, and are collected in H. This vessel is simply to detect smoking, he having found that it happened only when the pressure was di- minished at the burner, and that it could be stopped by a rein- statement of the normal pressure, p represents an aspirator, in which are collected the waste gases. Another one, not shown in the sketch, serves to contain the gas analyzed. Both are filled with water covered with a film of oil. The oxygen passes through a jar s filled with soda-lime, a bottle o fur- nished with a thermometer, a cock t as regulator of the flow, and one or more wash-bottles q containing sulphuric acid. The calorimeter-chamber c contains 5200 cc. (4.6 qts.) of water. 5 or 6 grams (77 to 92.5 grains) of coal were used, with 2 to 4 grams (31 to 62 grains) of sugar-carbon of a known calorific value. The temperature of the bath rose about 10° C, and the experiment generally lasted an hour. The sugar-carbon was first kindled in the upper part of the burner, the under portion burning first. From this sparks W. THOMPSON'S CALORIMETER. IJ ivcre thrown to the coal, and it soon kindled. The oxygen ilowed in by g and e. When combustion was well under way and had reached the lower portions of the coal, g was shut off and /opened. Schwackhofer obtained complete combustion of the sugar- carbon and coal, with no formation of black, and no residue of coke. The gaseous product of the combustion was generally of the following composition: Carbonic acid 50 to 60 percent; . Carbonic oxide 1.2 to 0.3 '' "■ Oxygen 10 to 1 5 '' " Nitrogen... 30 to 40 " " arising principally from the fact that to keep up the normal pressure the combustion-chamber was in communication with the open air. The cinders were weighed after each test. This apparatus should give exact results, but its use is complicated. The long duration of the test requires impor- tant corrections for influence of external heat, and it needs several thermometers. W. THOMPSON'S CALORIMETER. W. Thompson devised a calorimeter in which the com- bustion is started by a jet of oxygen, but the waste gases in- stead of passing through a coil bubble up through the water of the calorimetric bath. In this apparatus the uncombined gases are naturally neglected. (See Fig. ii.) It is an appa- ratus, as the inventor says, not intended for scientific re- searches, but for handy use of mechanics or '' for popular use." rt: is a galvanized-iron gas-holder containing oxygen ; d, a stop-cock regulating the flow of water to this holder; d, stop- cock for gas; e, rubber tube; /, level-gauge; g, pressure- gauge; /i, bell-glass covering the platinum crucible ^, in which the coal is burnt ; / is a support of earthenware suspended 38 CALORIFIC POWER OF FUELS. from the bell-glass by metal springs, and intended to insulate the crucible and prevent too quick cooling; /« is a glass jar containing 2000 grams (4.4 lbs.) of water, forming the calori- metric bath. Water cannot enter the bell h while the cock j Fig. II. — W. Thompson Calorimeter. is closed, and it is opened only when the pressure in the gas-holder is sufficient ; ?2 is a glass jar filled with water and surrounding the calorimetric jar, and / is the agitator. One gram of fuel is put into the crucible, and on this is placed a small cotton wick impregnated with bichromate of potash. This is lighted at the instant of putting into the jar, and its combustion aided by the oxygen kindles the fuel. This is an imperfect apparatus, and will give in most cases only unsatisfactory results. Still it is in rather common use in the shops of England, where it serves principally as a com- parative measure, the errors being considered constant. BARRUS S CALORIMETER. The Barrus calorimeter is a modification of the one just mentioned. While it requires considerable care in using to get correct results, yet it is one of the simplest and most in- expensive. BARRUS'S CALORIMETER. 39 As described by Mr. Barrus, " it consists of a glass beaker (Fig. 12) 5 inches in diameter and ii inches high, which P^ can be obtained of most dealers in chemical apparatus. The combus- tion-chamber is of special form, and consists of a glass bell having a notched rib around the lower edge and a head just above the top, with a tube projecting a considerable dis- tance above the upper end. The bell is 2J- inches inside diameter, 5|- inches high, and the tube above is J inch inside diameter and extends beyond the bell a distance of 9 inches. The base consists of a cir- cular plate of brass 4 inches in diam- eter, with three clips fastened on the upper side for holding down the combustion-chamber. The base is perforated, and the under side has three pieces of cork attached, which serve as feet. To the centre of the upper side of the plate is attached a cup for holding the platinum crucible in which the coal is burned. To the upper end of the bell, beneath the head, a hood is attached made of wire gauze, which sefves to intercept the rising bubbles of gas and retard their escape from the water. The top of the tube is fitted with a cork, and through this is inserted a small glass tube which carries the oxygen to the lower part of the combustion- chamber. This tube is movable up and down, and to some extent sideways, so as to direct the current of oxygen to any part of the crucible and to adjust it to a proper distance from the burning coal." The method of working it can be easily seen from the description and cut. In burning very smoky coals he mixes Fig. 12. — Barrus Calorim- eter, 40 CALORIFIC POWER OF FUELS. them with a proportion of non-smoking coal of known calo- rific value, and when anthracite or coke is burnt he mixes it with a small portion of bituminous coal. In Mr. Barrus's hands very satisfactory results have been obtained. HARTLEY AND JUNKER' S CALORIMETER. Hartley's calorimeter is an apparatus of constant pressure iind continued combustion. The gas measured by a meter is burnt in a Bunsen burner surrounded by a cylindrical copper Fig. 13. — Junker Calorimeter. vessel filled with water, which is constantly renewed. The flow of liquid is such as to avoid much heating and time suf- ficient is used to increase the temperature so as to have a good thermometric observation. The volume or weight of the water is determined at such intervals and the thermometric readings taken often enough to obtain an average. JUNKER'S CALORIMETER \\ Hugo Junker's modification of the apparatus rendered it more exact. It has been used for some time in Germany and in the United States. It is composed (Fig. 13) of a gas-meter a^ preceded by a very sensitive regulator b. On leaving the meter the gas. passes to a Bunsen burner c. The products of combustion give up their heat to a calorimetric tube d^ through which regularly flows a stream of water. The temperature of the gases is regulated by means of a thermom- eter e. In order to keep the flow of water as regular as pos- sible, it flows from the supply-tube g into a small reservoir kept at a constant level governed by the tube h. The water passes through i to the calorimeter and escapes at k, run-, ning into the glass in which it is measured or weighed. The graduated tube / is to catch the condensed water from the interior of the calorimeter. The thermometer in shows the heat of the escaping water, and n that of the water enter- ing the calorimeter. To calculate the calories generated during the combustion proceed as follows : Measure the quantity of water which runs through it in one minute, take the temperature of the two thermometers, and note the flow of gas. The heat of combustion per cubic metre of burnt gas is obtained by multiplying the volume of water flowing per minute by the difference of the two temper- atures and dividing the product by the gas volume burnt per minute. Thus : Volume of water flowing per minute 902.3 cc. *' " gas burnt per minute. ..... . 2500.0 cc. Temperature at inlet 13. 1° C. '' outlet 27.5" C. 902.3 X [2-]^^ - 13.1^ . ^ 1 • Q z= — ^196 calories. 42 CALORIFIC POWER OF FUELS. The gas tested has a value of 5 196 calories per cubic metre. Since the calorie is 3.968 times the B. T. U., and the cubic metre is 35.316 times the cubic foot, multiplying 1 . 1 • , 3.968 the calories per cubic metre by — =:0. Ii2^c; will give 35.316 ^ B. T. U.'s per cubic foot. Multiplying, then, 5196 X 0.1 1235 = 583.8 B. T. U.'s per cubic foot. The above example considered the volume of the .water. It is sometimes advisable to consider the weight instead. The following example illustrates this: Weight of water used during the test. . . , 2000 grams. Volume of gas burnt 7-23 litres. Temperature at inlet i4-4° C. *' outlet 36.5° C. Then 2QQO X (36.5 - 14-4) ^ ^ 1 • K- Q = = 6102 calories per cubic metre, 7.23 ^ and 6102 X 0.1 1235 r= 685.6 B. T. U. per cubic foot. Two causes of error may occur. It is not certain that the combustion of the gas in the burner is regular; indications by gas-meters are not always very sure, the start being capricious. But these do not have much weight in its use for industrial purposes, for which it is chiefly designed. The results are very near those obtained by other methods. Stohmann, whose competence in such matters is universally recognized, says they give good results. Bueb-Dessau, to prove the calorimeter, burnt hydrogen prepared by electrical decomposition, and obtained after cor- rections for thermometer and barometer 34150 calories per LEWIS THOMPSON'S CALORIMETER. 43 Icilogram — a difference of 350 calories from the usual number, 34500, or only 9 thousandths. ■ Prof. Jacobus has determined that there is a constant error due to neglect of latent heat of moisture in products of com- bustion of —2 per cent in the determinations with this appa- ratus; otherwise it is very satisfactory. LEWIS THOMPSON'S CALORIMETER. Lewis Thompson's calorimeter has been used in England for some time. It gives only approximate results, but as the errors are of the same kind in each case, the results are com- parable, and it has been found serviceable in industrial works where quick and comparative observations are required. The apparatus (Fig. 14) is composed of a glass calorimeter- bath H containing water, a copper cylinder E in which the Fig. 14. — L. Thompson Calorimeter. Fig. 15. — Calorimeter IN Action. mixture of coal and potassa chlorate is placed, and surmounted by the nitrate of lead fuse F. Enclosing this cylinder is a bell D, having a tube C carrying a stop-cock. The cock is closed before putting it in position in the water. iT is a cleaner for the tube C, and y is a thermometer. 44 CALORIFIC POWER OF FUELS. The fuze is lighted, and the whole quickly put in the jar of water. The mixture of combustible and potassium chlorate soon ignites and burns, all the gases generated being forced out at the bottom of the bell through the perforations, and bubble up through the liquid. After the combustion is finished the temperature is taken and the heat-units calculated. From 8 to lo parts of oxidizing mixture is recommended for one of coal; but if the coal is very rich this must be increased to 1 1 parts, calculated on the crude coal. With pure coal, cinders out, the extreme limits are 1 1 and 14 parts. It would probably increase the accuracy of the method, if the same quantity of oxidizing mixture was employed, what- ever the kind of coal used, and to mix with it inert substances, as silica or ground porcelain, in quantity varying with the richness of the coal. Scheurer-Kestner tested this apparatus very carefully, using a great variety of fuels whose heats had been previously ascertained by means of Favre and Silbermann's calorimeter. He found some 15 per cent deficit in the figures, and after correcting by this amount the results varied only a few per cent from those actually obtained. In thirty different kinds of coal tested the average was 1.8 per cent too low. The use of this calorimeter requires some skill. Its imper- fect insulation requires prompt reading and rapid combustion. Care must be taken to work at temperatures very close to that of the room, as the calorimetric bath is not protected. The proportions of the mixture used vary, not only with each kind of coal, but for each sample, on account of the propor- tions of cinders. Fat coals require more oxidizer than lean coals, as it is evident an increase in quantity of cinders should require a decrease in oxidizer. But in changing the propor- tions of oxidizer a certain difference in elevation of tempera- 'ture is necessarily produced by the heat of solution of the salts left after the combustion. These various causes render its working rather delicate, and always uncertain. CHAPTER V. CALORIMETERS WITH CONSTANT VOLUME. The results obtained with a calorimeter of constant volume- are not exactly the same as those obtained with one of con- stant pressure ; but for solid or liquid substances the difference is too small to consider, since the volume, as well as that of the water produced, is inconsiderable in relation to the volume of gas employed. As regards the correction for contraction and expansion of the gases, they also are inconsiderable. In his Traite de Me'canique Berthelot has shown that the heat generated by a reaction between gases at constant pressure is equal to the heat of combination at constant volume at any temperature whatever, increased by the pre- ceding product counting from absolute zero ; and he gives the following formula for passing from one system to the other : QTp = QT, + o.5424(A^- N') + o.oo2(.Y - N')t, QTp being the heat generated by the reaction at constant pressure, and at the temperature T counting from ordinary zero; QT^, the heat generated by the reaction at same tem- perature and constant volume ; N, the number of units of molecular volume occupied by the components, these being taken according to usage equal to 22.32 litres under normal pressure at 0° ; N\ the corresponding number of units of molecular volume occupied by the product of the reaction. As example, take the combustion of carbonic oxide at 15°. Then we have CO -[- O == CC generates at constant volume 68 calories.* * These numbers refer to molecular weights. 45 46 CALORIFIC POWER OF FUELS. To pass from this to the heat given off under constant pressure, observe that CO occupies a unit of volume and O a half unit. Then N = li- CO, occupies a unit of volume and N' = I. Hence N-N'^^.j At o° there would be, then, for the difference between the heat of combustion at constant pressure and that at constant volume, + 0.542 X \— +0.271 calories. At + 15° add to this + 0.015, which increases the cor- rection then to 0.286. The heat of combustion of carbonic oxide at constant pressure and 15° is then + 68.29 calories. With a solid or liquid, this volume in relation to those of the gases formed may be practically neglected, the same as with the water; all reduce then to the contraction and expansion of the gases. Thus, for naphthalin, this correc- tion does not exceed 8.8 in 9692 calories — leSs than o. i per cent. In case of solids or liquids with unknown molecular weight, as with fuels generally, this difference m^y still be approximately calculated, as it is sufficient to know the volume of oxygen used in the combustion and that of the gases pro- duced. The first calorimeter of constant volume in date is that of Thomas Andrews, who in 1848 published results obtained with a closed calorimeter. The calorimeter was not applicable to solids or liquids ; the combustion of the gases was con- ducted as in a eudiometer, but he did not take all the precautions necessary to be certain of complete combustion. ANDREWS' CALORIMETER. 4/ ^Nevertheless, the results obtained for certain gases are remarkable, considering the elementary character of his apparatus and working. The combustion of solids, on the contrary, gave worthless results. The calorimetric bomb of Berthelot and Vielle seems able to replace advantageously all the other calorimeters as much iDy its convenience as by its certainty of results. Since Berthelot and Vielle's original form was published many minor changes have been made in the bomb. All the modern workers seem to prefer some modification of this form, m preference to any of the other and older kinds. There are so many points of superiority possessed by the bomb in ease and rapidity of working, accuracy, convenience, etc., which Jhave caused it to be universally used. ANDREWS' CALORIMETER. In 1848 Andrews published his labors on the heat of combustion of bodies, and notably on that disengaged by combustion of different gases. He used a cal- orimeter of constant volume, in which the com- bustion-chamber was a copper cylinder (Fig. 16) weighing 170 grams (6 ounces), of 380 > •a 11 pecific Gravity of Charcoal. ounds of Charcoal in a Bushel. m fU 0-. (75 Cl, 1. 000 4469 26.22 0.625 32.89 O.8S5 3955 22.75 0.481 25. 3^ 0.885 3821 21.62 0.401 21.10 0.772 3450 25.74 0.447 28.78 0.815 3643 21.00 0.550 29.94 0.728 3254 23.80 0.387 20.36 0.728 3254 22.43 0.400 21.05 0.724 3236 19.62 0.518 27.26 0.681 3044 22.56 0.418 22.00 0.644 2878 21.43 0.431 22.68 0.565 2525 24.72 0.238 12.52 0.605 2704 21.59 0.406 21.36 0.597 2668 20.04 0.370 19.47 0.551 2463 23.73 0.333 17-52 0.535 2391 23.60 0.274 19.68 0.567 2534 20.79 0.237 12.47 0.478 2137 24.88 0.385 20.26 0.426 1904 26.76 0.298 15. 68 0.418 1868 24.35 0.293 15.42 0.397 1774 25.00 0.245 12.85 0.552 2333 25.29 0.379 19.74 0.563 2516 21.81 0.383 20.15 > JJt3 I. 00 0.86 0.81 0.77 0.75 0.71 0.69 0.65 65 60 56 56 54 54 52 51 48 43 42 40 52 0.52 CHAPTER VIII. LIQUID FUELS. PETROLEUM— SHALE OILS— GAS OIL. Of the many oils capable of use as fuel, only those of min- eral origin are used, the others being too costly and possess^ ing no advantage. The mineral oils comprehend the liquid hydrocarbons extracted from bituminous schist or coal and its congeners by^ distillation, as well as the oils which exist already formed in the earth, and called by the special name oi petroleum. While the former are seldom employed in heating, petro- leum has become an important fuel in the countries which produce it. Its special qualities, light weight, and low price per calorie compared with other fuels insure a great future. The knowledge of its heat of combustion has become, then, of considerable interest. Its ultimate percentage composition varies within rather close limits, yet it is of a very complex proximate composi- tion. The industry of refining crude petroleum extracts from it some 50 per cent of refined oil for use in lamps, and hav- j ing a density of 45° to 46° Beaume, boiling-point 170° C. \ (328° F.); 10 per cent of naphtha with a lower density and * boiling-point; and 20 per cent of paraffin oil of a higher den- sity and boiling-point. Crude petroleum contains a large number of hydrocarbons. of the general formula C^R2n+2, and running from CH^ to CijHg^, with many isometric modifications. The industrial treatment modifies it profoundly. Hydrocarbons containing 88 LIQUID FUELS. 89 95 per cent of carbon have been found in the products of distillation.^ The vast quantities of petroleum possessed by the United States, Russia, and other countries, and its enormous heat value, early attracted the attention of engineers. Since then it has been found in greater or less quantities in every quarter of the globe, and is now being produced and used by the thousand tons. Probably the largest quantity and the most prolific wells are in Russia, on or near the Caspian Sea. Only a small portion of the territory has yet been opened, but the yield amounts to several million barrels annually, and some of the wells have produced several thousand barrels daily. The amount produced in the United States is greater than that of any other country, as the demand for the oil has forced the producers to constantly increase their facilities, and in addition the oil is of a quality better suited to manu- facture of the various grades. Canada, Roumania, Burmah, Australia, Peru, India, Java, and other localities have produced smaller quantities. New and large fields are being discovered now, and probably we have hardly yet entered on its field of use for heating pur- poses. Among the first to use liquid fuel, and the first to bring its use to a state of perfection, must be mentioned the Rus- sians. The large quantity of oil produced at such fabulously low prices, and the high price of coal, led them early to its use under boilers, both stationary and movable. For years they have used it exclusively in their locomotives and in many marine engines. At first the crude oil was used, but after- wards astatki, or residuum from the first distillation. Special burners were invented in large numbers, and now its use is a settled fact and increasing. * Wurtz, Dictionnaire de Chimie, Supplement. 90 CALORIFIC POWER OF FUELS. In other countries the same great incentive did not exist, and the development was slower. In the United States the large demand for illuminating and lubricating oils consumed almost the entire output; and it must be remembered that American oil is more easily manufactured into such products than the Russian article. In England the large accumulation of shale oil conse- quent on the discovery of the yield of paraffin in American oil, induced them to use some as fuel. But this state of affairs is now over and the shale oil is used but little for heating. Of all the fuels possible, liquid fuels offer the superior ad- vantages of high calorific power and small bulk. By actual test 1 60 gallons of oil has done as much work in water evap- oration as 3 tons of coal. The composition of petroleum may be deduced from the following analyses : Composition and Value of Petroleum. Russian crude light. . " " heavy " refuse Pennsylvania crude . West Virginia crude. •Canada crude Ohio crude Galicia crude Java crude c omposition Carbon. Hydro- gen. Oxygen. 86.3 13.6 O.I 86.5 12.3 I.I 87.1 II. 7 1.2 84.9 13-7 1.4 86.6 12.9 0.5 84-3 13-4 2.3 80.2 17. 1 2.7 85.3 12.6 2.1 87.1 12.0 0.9 Heating Power, B. T. U. 22,628 19,440 19,260 19,224 21,240 20,410 21,600 18,416 19.496 It will be seen that, pound for pound, its value as a fuel should be greater than that of coal, and actual test shows :such to be the case. Some experiments made at the Hecla Engineering Works, Preston, England, and lasting two days, used a marine boiler. LIQUID FUELS. 9 1 fc> The first day natural draft was used, the second a Kortin blower. The oil was blast-furnace oil from Sheffield, and contained : Per" cent. Carbon 83.54 Hydrogen lO- 59 Oxygen S-94 Sulphur ,. 0.09 100.16 By Thompson's calorimeter its value was 16080 B. T. U. Equivalent to water at 2 12 °F 16.66 pounds. The results were: First day, 14.97 lbs. ; second day, 14.2 £ lbs., — a yield of 89.87 and 85.25 per cent of the theoret- ical. A series of tests made at South Lambeth with a Cornisb. boiler showed 20.8 lbs. evaporation; average of several days,, 19.5 lbs. The same boiler with the best Aberdeen eoall yielded 6.5 lbs., — an advantage of 3 to i in favor of the oil. Mr. Urquhart, in reporting his tests with locomotives irt 1884, says : ' * The former (astatki) has a theoretical evaporative power of 16.2 lbs. of water per pound of fuel, and the latter (anthracite) of 12.2 lbs. at an effective pressure of 8 atmospheres, or 12a lbs. per square inch ; hence petroleum has, weight for weighty 33 per cent higher evaporative value than anthracite. Now,, in locomotive practice, a mean evaporation of from 7 to> ']\ lbs. of water per pound of anthracite is about what is gener^ ally obtained, thus giving about 60 per cent of efficiency,, while 40 per cent of heating power is unavoidably lost. But with petroleum an evaporation of 12.25 lbs. is practically ob- 12.25 . "" tained, giving — ^ — = 75 per cent efficiency. Thus, in the first place, petroleum is theoretically 33 per cent superior 9^ a CALORIFIC POWER OF FUELS, to anthracite in evaporative power; and, secondly, its useful effect is 15 per cent greater, being 75 per cent instead of 60 per cent ; while, thirdly, weight for weight, the practical evaporative value of petroleum must be reckoned as at least 12.25 - 7-5Q . ,, 12.25-7.00 from -— 3= 61 per cent to j-^ = 75 per cent higher than that of anthracite." Add to the above advantages the fact that no ashes are produced, no coal to be handled, no smoke, no dust, none of the usual unpleasant accompaniments of ordinary coal-burn- ing practice, and an idea can be had of the benefits not to be measured by actual percentages, etc. The first calorimetric experiments were published by Ste. -Claire Deville in 1868 or 1869, using a large calorimeter especially constructed for the work. Mahler used the bomb. The liquids were burnt in the bomb under nearly the same conditions as solids, when they had no appreciable vapor tension. When they had considerable vapor tension (light oils, for instance) Berthelot enclosed them in a closed vessel, the bottom being platinum and the top formed by a pellicle of gun-cotton. Others have made determinations by nearly the same methods, and a list of those available will be found on pages 251, 252, and 253. For burning liquid fuel the best burner is that which atomizes or sprays the fuel. By thus forming a fine mist an approximation to the theoretical fuel, gas, is obtained. Several methods are in use for this purpose. By some the oils are vaporized by heat ; but this is applicable only to light oils, which are not much used. The favorite method is by having the burner so constructed that the oil is forced out in a spray and at the same time mixed with the air necessary for its combustion. By this means a solid sheet of flame is pro- duced, and may be made of any length desired ; in some cases lengths of 100 feet have been reached. When using the fuel oil commonly used in the United LIQUID FUELS. Ql^ States air sprayers are sufficient, as this oil is a distilled product and contains none of the very heavy solid portions of the crude oil. In Russia and in Canada, however, the case is different, as in these countries the fuel oil is the residuum from the distillation and contains all the heavy and none of the light oils. In this case steam is used as an atom- izing agent, and it acts in virtue of its heat as well as its force. The various methods depending on the distillation and decomposition at high temperatures are not considered here, as the products formed are gases and will be considered as belonging to Chapter IX. In actual practice results have been and are being ob- tained which agree with and at times exceed the predicted ones. Many tests have been published showing an efficiency of 85 to 90 per cent of the theoretical evaporative power, and an evaporation of from 19 to 25 lbs. per pound of fuel has been frequently obtained. Carefully conducted tests have reached figures much in excess of these. Admiral Selwyn in 1884, at London, wdth a Cornish boiler having a fire-brick combustion-chamber built inside the flue, obtained at different times an evaporation of 46, 29, 24, 33, 23, 29, 33, 37, 29, 35, and 46 lbs. of water per pound of fuel. The products of combustion in the following table show- how complete the combustion was and how small an excess of air was needed. CO, 14.19 18.08 CO 5.20 0.34 0.78 0.34 Hydrocarbons. . . 1.30 None. H Not determined. None. N 78.53 81.24 To have the best results, the burner must be so regulated as to have a flame bordering on, but not quite, smoky. Thus gic CALORIFIC POWER OF FUELS, sufficient and not too much air is obtained. The quantity of steam needed to atomize the oil at Moscow is 4 per cent of the water evaporated. Since then numerous similar results have been reached. Actual tests made on locomotives of the Grazi and Tsar^ itzin line, in Russia, show for one year: Eight-wheeled Engines with Coal. No. of Cars to Train. Distance Run by Locomotives. Coal burnt per Mile. Cost. 37-51 511,995 m. 81.43 lbs. 22.6 C. With Petroleum Residuum. No. of Cars to Train. 'Distance Run by Locomotives. Oil Burnt per Mile. Cost. 38.08 868,712 m. 45.83 lbs. 13.0 C. No. of Cars to Train. Distance Run uy Locomotives. Coal Burnt per Mile. Cost. 26.32 1,341,681 m. 57.25 lbs. 15.6 c. With Petroleum Residuum. No. of Cars to Train. ^t^oc-omo^iTes'^ Oil Burnt per Mile. Cost. 25.45 1,487,333 m. 32.23 lbs. 9.0 c. Besides use for heating boilers, liquid fuel has been used with good results in puddling-furnaces, glass-works, smelting- furnaces, brick-making, lime-burning, and in almost every place where coal would be used. In some cases where fine adjustment of temperatures has been needed it has been a strong competitor to gas itself. LIQUID FUELS. ^id Many of the results obtained are far above the theoreti- cal quantities based on the usual calorific values of carbon, hydrogen, etc. To explain this it must be remembered that the value usually given to carbon is its value as a solid^ whereas when we vaporize oils we approach or actually reach the gaseous state, and should therefore have greater values. The calorific value of carbon solid is 8137 calories (charcoal) and of carbon vapor 11,328 calories (see page 73), showing aa increase of 39 per cent in carbon value. With a sample of oil containing 86. 6C, 12. 9H, 0.5O, the two values would be 11,475 and 14,759 calories (20,655 and 26,566 B. T. U.). Again, we do not know the actual state of combination existing among the atoms of carbon, hydrogen, and oxygen. That they do not exist as in the combinations obtained by distillation is known, and many unavailing attempts have been made to solve the problem. The presence of steam in some of the burners complicates the question still further, as there is no doubt but that a rearrangement of some of the atoms occurs and new compounds are formed. That this is the case is easily shown by the difference in. the quantity of gas produced by the decomposition of oil with and without steam. In the former case only 150 to 200 cubic feet are produced from a gallon, while in the latter as high as 1000 cubic feet or more. Oils other than mineral may be, and at exceptional times are, used. Their calorific power is high, as may be seen from Table i. Their use, however, is so infrequent that special mention of this is not necessary here. CHAPTER IX. GASEOUS FUELS. The heat of combustion of gaseous combustibles has been determined for a great many compounds, definite and pure. That of the industrial gases has been determined by different operators and in different ways, with more or less happy results. Its determination is often one of the greatest com- mercial interest, since it is used in domestic heating as well as in industrial appliances, where it is necessary to obtain definite, regular working. It serves also to furnish motive power to gas-engines, in which the heat of combustion is not without importance. Finally, it is well to know the heat produced in air or water-gas apparatus, if we wish to reach the best condition for their production and use. For heating steam-boilers gas has given good results and a very high evaporative effect. It is easily regulated, and thus any required heat can be produced by simply turning a valve. No smoke is generated, no soot or deposit of any kind produced in the flues, and no ashes to take out of the ash-pit. The fireplace needs repairing but seldom, and the boiler is heated evenly and regularly, there being no danger of burning out in strongly heated spots, as no such spots exist. In metallurgical furnaces, gas possesses a decided advan- tage in its long, clean, easily managed, intense flame, and this advantage has been long recognized. A flame of 25 feet or more in length is easily produced, and it is practically uniform for its whole extent. Part of the heat usually lost up the chimney can be utilized to heat the air-supply, and no more is supplied than just enough for perfect combustion. Using gas as fuel enables the metallurgist to use poor 92 GASEOUS FUELS. 93 grades of coal, and all variations in quality may be eliminated, a uniform product being had by storing the gas in a holder, or by making proper arrangement of different generators so that an average will be obtained. In several cases where hand-fed coal fires have been tried against fires burning gas from the same coal, better results have been obtained, due to the possi- bility of more closely adjusted regulation. The tests made at Brieg may be cited. Here each boiler had 141.25 square feet of heating-surface and steam-pressure 6 to 7 atmospheres. No. I boiler was hand-fired ; No. 2 was gas-fired. The evaporation in pounds per pound of fuel was : No. 1 8.34 8.74 8.28 4.02 2.569 2.764 No. 2 9.86 9.73 10.07 5-44- 3.251 3.158 Increase... 18^ 12^ 20^ 35^ 25^ 14^ HEAT OF COMBUSTION OF GASES FROM ANALYSIS. When the chemical composition of a gas is known exactly, its heat of combustion can be correctly calculated ; but \x\ absence of a correct analysis, the calorimeter must be used. Knowing the proximate composition of a combustible gas, that is, the proportion of chemically defined components as well as their heats of combustion, it is sufficient to add the numbers obtained for each constituent gas. Take, for example, the analysis of illuminating gas of Manchester as given by Bunsen: Hydrogen 45-58 Marsh gas (CHJ 34.90 Carbonic oxide...., 6.64 Ethylene (C,H,)r 4.08 Butylene (C,H3) 2.38 " i Sulphydric acid , 0.29 Nitrogen ,.,.. 2.46 Carbonic acid 3.67 100.00 94 CALORIFIC POWER OF FUELS. The calculation is as follows: Components, No.of Litres per Cubic Metre. Weigfhtper Cubic Metre at 0° and 70° mm. Grams. Heat of Combustion per Cubic Metre. Calculated Calories. HvHrocpn 455.8 369 40.8 23.8 66.4 2.9 cubic metre. 89.61 715.58 1251.94 2503.88 1251.50 2551.99 3066 9340 14980 29042 3057 1 1400 1395 3169 611 690 201 33 6099 Marsh gas, CH4 defiant gas, C2H4 Butylene, C4H8 CartDonic oxide Sulphydric acid, H2S... Total calories per City of Manchester gas, as analyzed by Bunsen, gives, then, with complete combustion, 6099 calories per cubic metre (685 B. T. U. per cubic foot). If, however, only the actual ultimate composition of the gas is known or the total percentage of carbon, hydrogen, oxygen and nitrogen, then the calculated result will differ from the experimental one. This is because the heat units of the elements added together do not make those of the compound, as the heat of combination of the different constituent gases is not allowed for. If this factor is known, then it can be used as a correction and the correct heat determined. This heat of combination of the elements to form the component gases will be seen in comparing the calculated and the actual heat of combustion of the following gases : Gases. Marsh gas. . defiant gas. Acetylene. . Benzene . . . . Formulae. Carbon. Hydro- gen. Calculated Heat. Actual He^t. CH4 C2H4 C2H2 CeHe 75. 85.7 92.3 92.3 25. 14.3 7-7 7.7 14685 I1859 IOTI4 IOII4 13343 12182 12142 12410 Differ- ence. + 1342 — 323 — 202S — 2296 It will also be seen, that although two gases may have the same percentage composition of the elements, yet the heat of combustion may be different owing to the action of the various physical forces at work in molecular condensation, etc. GASEOUS FUELS. 9$ COAL GAS. The heat of combustion of illuminating gas obtained froni the distillation of coal in closed retorts is very variable. It depends not only on the nature of the fuel, but also on the rapidity of the distillation and the heat by which it is accom' plished. The heat of combustion varies from 5200 to 630(i calories per cubic metre. It cannot be represented by any- average number. According to Witz, at the same gas-works and with th6 same fuel, yields may occur from 4719 to 5425 calories. According to Bueb-Dessau, the illuminating gas of the same city during the same day will sometimes vary 20 per cent. Dr. Birchmore reports the same result from his examinations of the gas of Brooklyn, N. Y. We are not certain that the composition assigned to coal gas by analysis corresponds always to the gas as obtained by distillation ; in Europe, especially, a portion of the heavy hydrocarbons is taken out for sale separately, and the deficiency supplied by cheaper oils. From several experiments which he made, Bueb-Dessau^ thought that the heat of combustion of illuminating gas was directly proportional to the candle power; but in addition to this being opposed to the theory of heat, the experiments of Aguitton show the contrary. He concluded from his deter- minations that each illuminating gas of different candle power has a definite heat of combustion which corresponds to the intensity of the light. His experiments were carried on with more than a hundred samples, rich and poor, the former kind from cannel coal, the latter from the end of the run carried to an extreme. He represents by the following formula the * Bueb-Dessau cites the following among others: Candle-power. Heat-value. Gas of Dessau 14- 4400 calories Gas of Bremen 21.9 5977 Gas from cannel coal 26.0 6559 96 CALORIFIC POWER OF FUELS. relation between candle power and heat of combustion of a gas: c — iy^ 352.6 + 2280, in which c represents the heat of combustion and i the candle power. The formula seems to be applicable only between limits at which it has been verified — from 5 to 15 candles. Aguitton's determinations were made with the calorimetric bomb. The following table gives a rhum^ of his observations : ^ ,, „ Heat of Combustion Candle Power. p^^ ^^^.^^ ^^^^^^ 5 ^ 4043 6 4395 7 4748 8 5101 9 5453 10 5 806 II 6158 12 65 II 13 6864 14 72 16 15 7569 7c5q — 4043 ^-^— ^ — 352.6, coefficient adopted. The three samples of illuminating gas, analyzed and burnt in the bomb by Mahler and given in the table below, call for the following observations: Gas from Niddrie cannel coal, the most calorific per cubic metre is the least calorific per kilo- gram, because the density is greater than that of the other two. The richest in hydrogen by volume (Lavillette) is the poorest in calorific power per cubic metre, while the poorest in hydrogen by weight is the richest in calories per cubic metre. These are due to the low density of hydrogen, which I GASEOUS FUELS. 97 is less calorific by volume than the other hydrocarbons occur- ring in illuminating gas. Analysis by Weight. Heat of Combustion -a v s 1) Name. >> c , c bfi c c Fc^ -e-a c •a .s c3§ M a. n u i^ Q u E U u A, Oh Niddrle cannel. . 0.6367 43-33 13-50 16.84 9.26 14.96 6365 7735 Commentry coal. . 4046 43-74 21.46 24.96 7.08 5-75 5834 1 1 TOO Lavillette gas. . . 0.4033 42.25 21.34 21.23 6.83 8.33 5602 10764 A cubic metre of hydrogen develops 3091 calories in burning; a cubic metre of marsh gas develops 10038 calories; a cubic metre of olefiant gas, 15250 calories. GAS OF GASOGENES. The gasogenes, instead of transforming the fuel into car- bonic acid and water in a single combustion, produce this change in two distinct burnings, the first being to make a combustible gas and the second to burn this gas with air. In the first furnace, the coal, for example, is burnt in such a manner by feeding with an insufficient supply of air that a gaseous mixture is produced, containing principally carbonic oxide, besides nitrogen from the air. As the combustion has been well or poorly managed, it contains a less or greater quantity of carbonic acid, the production of which is avoided as much as possible. This is done by giving to the fuel only just enough air to form carbonic oxide, and not enough to form carbonic acid, even partially, and by making the bed of fuel quite deep. The heat produced by this combustion is not used, and consequently an important part of the calories of the coal is lost. Gasogene gas is then lower in calories, and inferior to coal gas, as commonly made by distillation. 9o CALORIFIC POWER OF FUELS. One kilogram of carbon burnt to carbonic oxide disen- gages 2489 calories, while i kilogram of carbon burnt to car- bonic acid generates 8137 calories. There is lost, then, in burning carbon to carbonic oxide in a gasogene about 30 per cent of the available calories. At first eight this method of working seems irrational, but for obtaining high temperatures there are practical advantages, whose importance far exceeds the loss of heat in the gaso- gene. It permits much more elevated temperatures, and the recovery of a large portion of the heat, which in direct sys- tems of heating in high temperature furnaces passes to the chimney as complete loss. There is actually an economy in the ordinary metallurgical methods even with this loss. By means of gasogenes, we produce three kinds of gaseous fuel : the gas called producer or air gas, formed by the incom- plete combustion of the fuel, with production of a mixed gas containing carbonic oxide and hydrogen compounds ; the gas called water gas, from the decomposition of water by carbon at a high temperature, with production of carbonic oxide, hydrogen, and hydrogen compounds; and the gas called mixed gas, from the mixture of the two preceding ones by a process which combines the production of the two gases in the same furnace. PRODUCER OR AIR GAS. We have said that air gas results from incomplete com- bustion, and that its formation causes a loss of one third of the calories resulting from the complete combustion of the fuel. These gases contain, naturally, the nitrogen of the air used, to which must be added that of the air necessary to change the carbonic oxide and the hydrogen to carbonic acid and water. The heat of combustion and the composition determined by different experimenters varies considerably, showing that they did not always work with average samples. GASEOUS FUELS. 99 The proportion of nitrogen in these gases reaches $6 to 60 per cent; that of carbonic oxide, 21 to 32 percent; that of ■of hydrogen, from traces to 17 per cent. The theoretical calculation for the combustion of carbon in air to a gas con- taining only carbonic oxide and nitrogen gives for the first 34.7 and for the second 65.3 per cent. By adopting for the composition of air the round numbers 79 and 21, and for the weight of oxygen 1.430 grams per litre, for carbon the atomic weight of 12, and for oxygen 16, 12 : 16 = 1000 grams : 1333 grams. A kilogram of carbon needs, then, i^ kilograms of oxygen. A litre of oxygen weighing 1.430 grams, 1333 grams would occupy 932 litres. These 932 Htres will give with carbon a double volume, or 1864 litres carbonic oxide. Multiplying , 932 litres by the coefficient 4.77 (see Table XIV), we obtain ^ the volume of the air corresponding, or 4445 litres. The J gases of combustion will be composed then of these 4445 litres of air and the 932 litres of increase in volume, or 5377 litres for i kilogram of carbon. The 4445 litres of air will contain (at 79 per cent) 3513 litres of nitrogen, or 65.3 per cent."^ The calculation is more complicated when we have fuel containing hydrogen, as one portion of the oxygen disappears by its combination with the hydrogen to form water. Take for example, a coal containing 90 per cent of carbon, 5 per cent of hydrogen, and 5 per cent of oxygen. Suppose i kilogram of this coal, under theoretical conditions, burnt in a gasogene, i.e., with perfect transformation of the carbon into carbonic oxide and no residues. This coal contains 900 grams carbon, 50 grams hydrogen, 50 grams oxygen. 900 * One pound of carbon requires 1.333 lbs. of oxygen; i cubic foot of oxygen weighs 0.08926 lb. ; 1.333 lbs. measure 14.93 cu. ft. These would give 29.86of CO. 14.93 X 4-77 = 71.216, and 71.216 -f 14.93 = 86.146, volume of gases of combustion. These contain 56.26 cu. ft. of nitrogen. 100 CALORIFIC POWER OF FUELS. grams carbon produce 2100 grams carbonic oxide, requiring 1200 grams oxygen. i2po grams oxygen occupy 839 litres. 50 grams hydrogen produce 450 grams water, and require 400 grams oxygen. These 400 grams oxygen occupy 279 litres. But the coal itself contains 50 grams oxygen, occupy- ing 35 litres. We have, then, 839 + 279 — 35 = 1083 htres of oxygen required, and to calculate the amount of air needed multiply by 4.77. This gives 5163 litres of air needed for the incom- plete combustion of i kilogram of carbon. These 5163 litres contain 4080 litres of nitrogen. To obtain the total volume of gases produced by the incomplete combustion, we may add to the volume of the air introduced the volume due to the formation of carbonic oxide, and this is equal to the volume of the oxygen used, or 839 litres. We have, then, 5163 + 839 = 6002 litres. But a quantity of oxygen has disappeared corresponding to the formation of the water, or 279 — 35 = 244 litres (35 litres exists in the coal as above), and 6002 — 244 =5758 litres of gas produced by the incomplete combustion of i kilogram of coal. Now, then, 5163 litres of air contain 4079 litres of nitro- gen, which would form - , or 70.8 per cent of the total 5758 gas. All these numbers are at 0° and 760 mm. pressure.* Generally gasogenes contain less nitrogen, different causes producing diminution, among which are the use of a lower *One pound of coal would be 6300 grains carbon, 350 grains oxygen^ and 350 grains hydrogen; 0.90 lb. carbon produces 2.1 lbs. carbonic oxide^ and needs 1.2 lbs. oxygen; 1.2 lbs. oxygen occupies 13.44 cu. ft.; 0.050 lb. hydrogen produces 0.450 lb. water, and needs 0.400 lb. oxygen, or 4.48 cu. ft. The 0.05 lb. of oxygen in the coal occupies 0.56 cu. ft. Then 13.444- 4.48 — 0.56 = 17.36 of oxygen required 17.36 X 4-77 = 82.81 cu. ft. of air, , containing 65.41 cu. ft. nitrogen. Total gases, 82.81 -}- 13-44 ~ 3-92 = 92.33, total volume of gas, and 65 41 = 70.8 per cent. 92.33 GASEOUS FUELS. lOI hydrogen coal than we have taken, and the" decomposition of the fuel in the body of the furnace with a certain quantity of aqueous vapor formed during the combustion, or from the moisture in the air supplied. Mahler determined the heat of combustion of a sample of gas from the Follembray glass-house, and found its composi tion per volume, using coal from Bethune, to be: Marsh gas 2 Hydrogen 12 Carbonic oxide 21 Carbonic acid 5 Nitrogen , 60 100 The heat of combustion calculated from its composition is:: Marsh gas 0.02 X 10038 = 200.8 Hydrogen 0.12 X 3091= 370.9 CO 0.2 1 X 3043 = 639.0 1210.^ With the bomb he found 12 12 calories. WATER GAS AND MIXED GAS. Water gas is produced when water is decomposed at high temperatures by fuels containing but little hydrogen, such as anthracite, charcoal, or coke. Mixed with hydrocarbon vapors, added to enrich it, or which may have been decom- posed with the aqueous vapor, it serves for the illumination of a great number of cities, principally in America. But this is not its only use, as it is used for heating, and also for gas- engines. Mixed with producer gas, it has become a powerful means of heating, especially where high temperatures are wanted. Water gas contains but little nitrogen : this is its main distinction from producer gas, and that which gives it a special value from an economical heating point of view. I02 CALORIFIC POWER OF FUELS. We have previously stated (page 97) that during the combustion of carbon in a gasogene, there occurs a genera- tion of nearly one third of the total heat were the fuel com- pletely burnt. Besides this, the combustion produces a gas containing about one third its weight of combustible gas and two thirds inert gas (nitrogen), which is mixed with it. These are important causes of two sources of loss in calories. In an air-gasogene one third of the calories is lost, since the gaseous products give up most of their sensible heat before being used. The 66 per cent of inert gas carries off an enormous quantity of heat to the chimney, and thence to the open air. It was with the idea of regaining or stopping these losses, or at least a large portion of them, that water gas originated. Aqueous vapor and carbon, when submitted to a high temperature, produce carbonic oxide and hydrogen. Theo- retically these are free from nitrogen ; but there is always present a small percentage for various causes. In the air gasogene 12 kilograms of carbon and 16 kilograms of oxy- gen (atomic weights) unite to form 28 kilograms of carbonic oxide. On the other hand, 12 kilograms of carbon and 18 kilograms of water form 28 kilograms of carbonic oxide and 2 kilograms of hydrogen. Then i kilogram of carbon fur- nishes 2.5 kilograms of gas composed of carbonic oxide and hydrogen. One kilogram of hydrogen has a caloric energy of 29042 calories.* These calories represent also the quantity of heat necessary to decompose the water; in the case of the water gas gasogene they are formed by the carbon burnt. The 12 kilograms of carbon will have to furnish, then, the calories necessary to decompose 18 kilograms of water; that is, 2 X 29042 = 58084 calories. * Water being considered as vapor. GASEOUS FUELS. 10$ But 12 kilograms of carbon, in burning, generate only 12 X 2473 = 29676 calories. To decompose the water, then, there is a shortage of force of 58084 — 29676 ~ 28408 calories for 2 kilograms of hydrogen, or 14204 calories for i kilo- gram. The heat must be furnished by an external source. In other terms, to gasify i kilogram of carbon there must be supplied 14204 -f- 6 = 2367 calories. As may be easily seen, this operation absorbs much heat, and the combustion of the water gas can give only the calo- ries used at first in forming it. The heat necessary for the decomposition of the water is actually taken from that of the preparatory period of the air gasogene, which makes a loss of one third of the total calories. In burning the water gas made under these conditions we utilize a part of the heat which would have been lost by the air gasogene only. The decomposition of water by carbon is not as simple as would appear from the equation H,0 + C = CO + H,. The lower portion of the fuel of the gasogene undergoes ordinary combustion on account of air being present; while in the upper portion the reaction takes place between the gaseous products formed in the lower portion and the heated carbon. The carbonic acid is then in contact with the heated carbon and is reduced to carbonic oxide: C + CO, = 2CO. I04 CALORIFIC POWER OF FUELS. ThuS; the reaction with the water would be 5H,0 + 3C = 2CO, + CO + loH ; carbonic acid being reduced to carbonic oxide in the final reaction, as in the case with the air gasogene. Nine kilograms of aqueous vapor and 6 kilograms of carbon produce i kilogram of hydrogen and 14 kilograms of carbonic oxide, that is, a mixed gas is produced containing about one half its volume of each gas. One cubic metre of hydrogen weighs 85.5 grams; one of carbonic oxide, 11 94 grams. Then the volumes occupied by each gas would be 11.69 ^^"^ hydrogen and 11. 13 for car- bojiic oxide, or 51.23 per cent of hydrogen and 48.77 per cent of carbonic oxide. From the foregoing account, it will be seen that the inter- mittent flow is a cause of great loss of caloric in the working of the water gasogene ; but when a gas is wanted solely for heating at high temperatures, it may be obtained by a mixed system working continuously. The gasogene is filled with a mixture of air and steam, the air being employed in the proper proportion to keep up the heat necessary, or, in other words, to furnish by the combustion of part of the carbon, the number of calories necessary to the gasifica- tion of the other part. We have seen (page 103) that to gasify i kilogram of carbon 2367 calories were needed. To maintain the heat this quantity must be produced by the action of the air. Mixed gases are poorer than water gas, as they contain more nitrogen and carbonic oxide and less hydrogen. Theo- retically, we should attain the result of furnishing the heat to the gasogene necessary to maintain the temperature by sup- plying the steam sufficiently superheated ; a gas very poor in nitrogen would then be made. But the superheating of steam causes new losses of heat. GASEOUS FUELS. 105 NATURAL GAS. Natural gas has been known for thousands of years in Asia, on the Caspian Sea, where it has long been a feature in religious services, but it is only recently that it has become of any use to man and played any part in the fuel world. The natural gas output in the United States has attracted considerable attention since 1875, ^.nd especially since 1880. This gas always accompanies petroleum, although petroleum does not always accompany the gas. The wells are situated in various portions of New York, Pennsylvania, Ohio, Indiana, West Virginia, Kentucky, Tennessee, Colorado, Cal- ifornia, and on the Canadian side also in numerous locations. Natural gas is not of a constant or uniform composition, A^arying very much according to the locality from which it is taken. The individual constituent gases vary between wide hmits, hydrogen at some places being almost wanting, while at others it is as high as 35 or 40 per cent. Marsh gas is in every case the principal constituent, but this runs down as low as 40 per cent in some analyses. Nitrogen is some- times absent, and when present in large amounts, it is suppos- able that the gas analyzed was contaminated with atmospheric air. The Ohio and Indiana fields yield gas of nearer a uniform composition than any of the others. The following table is typical : Hydrogen Marsh gas defiant gas Oxygen Carbonic oxide Carbonic acid Nitrogen Hydrogen sulphide Ohio. Fostoria 1.89 92.84 0.20 0.35 0.55 0,20 3-82 0.15 Findlay. 1.64 93-35 0.35 0.39 0.41 0.25 3-41 0.20 St.Mary's 1.94 93.85 0.20 0.35 0.44 0.23 2.98 0.21 Indiana. Muncie. 2.35 92.67 0.25 0.35 0.45 0.25 3-53 0.15 1.86 93-07 0.47 0.42 0.73 0.26 3.02 0.15 Kokomo. 1.42 94.16 0.30 0.30 0.55 0.29 2.80 0.18 io6 CALORIFIC POWER OF FUELS. In addition to difference in composition in different local- ities, the composition of the gas varies cons'derably from time to time in each well. This is shown by the following analyses made at different times within a period of three months from a well at Pittsburgh, Pa. : Hydrogen Marsh gas. . . . Olefiant gas. . . Illuminants ... Oxygen Carbonic oxide Carbonic acid. Nitrogen 1 2 3 4 5 9.64 14-45 20.02 26.T6 29.03 57.85 75.16 72.18 65-25 60.70 0.80 0.60 0.70 o.So 0.98 5.20 4.80 3.60 5-50 7-92 2.10 1.20 1. 10 0.80 0.78 1. 00 0.30 1. 00 0.80 0.58 0.00 0.30 0.80 60 0.00 23.41 2.89 0.00 00 0.00 35. q2 49-58 0.60 12 30 0.80 0.40 0.40 0.00 The quantity of gas used daily in the town of Findlay, Ohio, in 1890, was estimated by Professor Orton to be, for Glass-furnaces looooooo cubic feet. Iron mills lOOOOOOO "- " Other factories 6000000 *' '* Domestic use 4000000 '' '* Total per day 30000000 '' ** In Indiana, large wells have been opened and used as in Ohio. In Pennsylvania, several of the large rolling-mills and glass-houses near Pittsburg were formerly supplied with mill- ions of feet per day ; but the supply, used so lavishly, became exhausted. In Canada, at Fort Erie and Windsor are wells, the gas from which is piped across the river to Buffalo and Detroit respectively. All through the oil regions gas wells are to be found more or less, accompanying every well sunk. From the composition of the gas, it will readily be seen that it is a valuable source of heat, the calorific power reach- ing loooo calories or 1 100 B. T. U. per cubic foot. It is used for domestic purposes, steam, glass making, iron mills, brick burning, and numerous other ways, and until recently used wastefuUy in all. GASEOUS FUELS, IO7 As compared with coal, 57.25 pounds of coal or 63 pounds of" coke are about equal to 1000 cubic feet of the gas. The actual equivalent in steaming or furnace work varies with the furnace, and proj^ably with the people using it. Equivalent values of 14000 to 25000 cubic feet per ton of coal are reported, and hardly any two users will give the same yield. It seems to be especially adapted to glass making, giving a long, clean, ashless, smokeless flame, and hundreds of glass- pots were set up in the neighborhood of the wells, especially in Ohio. Each pot consumes from 58000 to 61000 cubic feet per 24 hours in window-glass works and from 31000 to 49000 cubic feet in flint-glass works, the difference being of course due to difference in burners and men, the gas being the same. In all cases where this gas is used the chief claim made, in addition to those of gases generally, has been cheapness, and it has been sold without any regard to its actual value. A comparison of its value with that of other gases is given by McMillin in the Report of the Ohio Geological Survey, vol. VI, page 544, as follows: 1000 feet natural gas will evaporate .... 893 pounds of water. ( < i i coal '' '' i ( 591 a <( water ** '' tt 262 it ( i producer gas** It OIL GAS. 115 There are several processes for producing gas from oiU usually petroleum or its derivatives. Some of them decom- pose the oil by means of heat alone, while others use steam, or steam and air together. The most successful pure oil process is the Pintsch ; this is used extensively in the large cities of Europe and America to obtain a gas for illuminating cars on railways. The gas is made by allowing the oil to fall drop by drop on a strongly heated surface. Complete decom- I08 CALORIFIC POWER OF FUELS. position occurs, and a gas of high candle-power is formed. This is collected, and after compression supplied to the con- sumers. It loses some 20 per cent of the illuminating power during compression. As a source of heat, its use is, so far, very limited. An analysis and heat test will be found in the tables. The Archer gas process is somewhat similar to the Pintsch, but the products of decomposition are generated at a com- paratively low temperature, and then superheated subse- quently so as to make the gas permanent. This gas is used for metallurgical purposes, but its use for heating boilers is very limited. The other gases made with steam or steam and air have been advertised or pushed as fuel gases for several years. Many plants have been established and failed. A few of the most prominent are mentioned in the tables. OTHER GASES. Gas has been obtained from destructive distillation of wood, rosin, fats, and other materials. They were used prin- cipally for illumination, and seldom if ever for heat. They are now made only in very exceptional cases. I CHAPTER X. CALORIFIC POWER OF COAL BURNT UNDER A STEAM-BOILER. FUEL USED AND WATER EVAPORATED. DISTRIBUTION OF THE HEAT PRODUCED. Experiments in heating steam-boilers have to deter- mine : 1. How much water is vaporized by a given quantity of coal, so as to compare it with other coals or fuels ; 2. The evaporative power of the steam-boiler used; 3. A comparison of the various styles of grates or meth- ods of heating applied to steam-boilers. In this book we will consider only the first case, the others being outside of its scope. The knowledge of the heat of combustion of coal and other fuels is closely connected with experiments in heating steam-boilers. It is not enough to know the proportion of water which the apparatus or the fuel tested will vaporize : we must also determine the number of calories lost. We must know, besides, the composition of the coal and its heat of combustion, to determine the proportion of calories used to that possible with perfect combustion. The first work in this direction worth mentioning was probably that done by Peclet in 1833, but his results were very crude, and are of no account now. The next were those made by Prof. Johnson, in 1842 and 1843, for the U. S. Navy Department, to determine the steaming powers of the log no CALORIFIC POWER OF FUELS. coals then in use. He analyzed and tested some thirty-five different coals, domestic and foreign. The tests were made with a specially built boiler, and careful and copious notes were taken all through. The chimney gases were analyzed, and an attempt made to determine their quantity. In 1891 Mr. W. Kent* reviewed his work, and found that, with correc- tions for the constants employed by Johnson, the tests were comparable with those made at the present time. The figures given in the tables as Johnson's are with Kent's corrections. The first experiments based on the knowledge of the composition and heat of combustion of coal were published in 1868 and 1869 in the Bulletin de la Socidt^ Industrielle de MulJwuse. Scheurer-Kestner remarks in the first part of this work, which he prosecuted later on with assistance of Meunier-Dollfus (/c'f. cit. p. i): **It is necessary to analyze the great difference found between the theoretical heat of combustion (at that time no actual determinations had been made) and the practical yield. '* Several elements of the calculation aid in making this shortage. The principal ones are : '* The heat of combustion of the coal; *' The composition of the coal; ** The composition of the cinders as drawn from the ash-pit ; ** The quantity of water vaporized and the temperature of the steam produced ; "The volume of gases introduced under the grate, and their temperature when they leave the boiler to pass into the chimney ; **The composition of the gaseous products of combus- tion ; * Engineering and Mining Journal, Oct. 1891. WEIGHT OF FUEL. 1 1 1 ''The temperature of the cinders at the time of dumping; '' The loss of caloric by radiation from the setting of the boiler." We must refer to mineral and organic as well as gas analysis to obtain the necessary elements for the distribution of the caloric produced by the combustion of the coal on a steam-boiler grate. To avoid referring to them, we will consider the composi- tion and heat of combustion of coal as known. (See tables.) WEIGHT OF FUEL. The coal used in the test should be kept under cover away from moisture and heat, so that the hygroscopic water it contains shall vary as little as possible from the time of taking the sample. Weigh the coal in the gross, and then weigh portions of about lOO kilograms (220 lbs.) on a scale sensible to y^Vo"- Where practicable, a box open at the top and holding 500 pounds of coal should be provided for each 25 square feet grate area, and in proportion for larger grates. It should be placed on the scales, and conveniently located for shoveling into the fire. The exact time of weighing should be noted and the exact weight set down. The weight should be taken at the instant of closing the fire-door. The box should be com- pletely emptied each time. The difference of weight at each firing will give the several quantities fired ; the differences of time will give the intervals between firing; and the differ- ence of time between successive charges will serve as a check on the record of the test. A chart or diagram should be made showing the regularity of the working, and it is well to keep the records in tabular form ; weights in one column, time in another. 112 CALORIFIC POWER OF FUELS. SAMPLING THE COAL. In all experiments for determining heat of combustion of fuels, the sampling must be done with the utmost care, espe- cially if the laboratory and working test are to be made at the same time. Samples accurately representing the coal of the working test must be kept in the laboratory, and when coal is tested which contains foreign matter and considerable moisture, too much care cannot be taken to prevent errors. The official method of the American Society of Mechanical Engineers is given in the Appendix, and answers the purpose very well. If very large quantities are to be sampled, remove a portion from each cart-load and then re-sample these as per directions above mentioned. It is not always necessary to resort to these -methods. When the coal comes from the same pit and level, experience has shown that a piece which seems to agree with the general character is usually sufficient. Care must be taken to avoid samples having too much hanging-wall or bed-rock. For twenty years the pure coal of Ronchamp taken from the same pit has given the same calorimetric test, when it con- tained from lo to 20 per cent of ash. Lord and Haas* showed that the same was true of many American mines, especially in Ohio and Pennsylvania. This being true, we could consider that in sampling we did not sample the coal, but the impurities; and that a sample showing the average impurities would give all that was needed, as we would know what the coal was. Care must be taken with regard to the moisture, and any coal showing much external moisture must be examined as near as possible to the original condition. For example, a coal containing lo per cent of moisture in the pile may, after sampling, crushing, and resampling, lose all but 4 or 5 per cent. If the moisture was determined in this coal while in as * Trans. Am. Inst. Min. Eng., Feb. 1897. ANALYSIS OF COAL. 113 large pieces as possible, this moisture would all be accounted for. In spite of all precautions, samples do not always agree in mineral content with the mass. The difference seems to be due not only to the unequal distribution of the foreign mineral matter throughout the coal, but principally to the difference in specific gravity between the coal and this mineral, so that the purer the coal the more satisfactory the sampling. Sometimes a coal is rich in foreign matter, and is contained in a tube open at one end. From this samples may be drawn showing differences of several per cents ; as for example, 12.49 and 16.74 per cent obtained in two successive cases. The following experiment shows how this happens and how to prevent it : 30 grams of coal, finely pulverized, and contain- ing 20 per cent of mineral, was put into a glass tube, which was closed with a cork and placed vertically, giving it slight taps to settle it down. In a short time most of the foreign material was at the bottom of the tube, the upper portion being nearly free. To avoid such an error the sample must be drawn only after thorough mixing, and without any shaking or jarring of the tube. It is well to use pastilles made up immediately after thorough mixing. A sample containing only 13 to 14 per cent of foreign matter has given from a tube, 12.20, 12.81, 13.12, 13.50, 14.42 per cent. ANALYSIS OF THE COAL. "No attempt will be made to treat the methods of ana- lyzing coal ; still, as this usually accompanies a calorimetric determination, some hints may be useful. Scheurer-Kestner usually burns the coal in tubes of white glass placed on an iron gutter. The same tube may thus serve several times if asbestos cloth be placed between the tube and the iron and the cooling be properly regulated. His tubes are 70 to 75 centimetres (27 to 29 inches) long and 15 to 20 millimetres 114 CALORinC POWER OF FUELS, (0.6 to 0.8 inch) inside diameter. They are filled with copper oxide in small pieces, except at the front end, which has a small piece of metallic copper, and at the back, where the platinum boat containing the coal is placed. Usually half a gram is used for a test, the coal having been previously dried at 100° to 105° C. (212° to 221° F.). Before putting in the sample the tube is heated to redness and thoroughly dried by means of a current of dry oxygen. The combustion is carried on so as to allow time enough for all the gas to be absorbed by the potash, during the first half of the time the bubbles passing through very slowly. There is no risk then of unburnt gases passing off. An iron or a platinum tube may be used in place of the glass one, but glass allows inspection at all times. An analysis should show the carbon, hydrogen, oxygen, nitrogen, sulphur, ash, and moisture, and they should be so given that the carbon, hydrogen, oxygen, nitrogen, sulphur, and ash should equal lOO per cent, the moisture being determined separately, or if preferred all but ash and moisture may foot up lOO, and those two be given separately. This latter method is the one which is followed by many of the European engineers, and will be found so in the tables given at the end of this book. If possible the approximate analysis should also be given. In determining the moisture too much care cannot be taken to expel all of it. With many coals, and especially our Western ones, the ordinary heating to 110° C. is not suffi- cient, Kent, Carpenter, Hale, and others have investigated this question, and find that a much higher temperature is needed, and must be employed. In some cases as high as 140° to 150° C. may be used with safety, and such tempera- tures are recommended by Carpenter, no appreciable amount of volatile matter being driven off. DURATION OF THE TEST. 115 ANALYSIS OF THE CINDERS. The cinders and ashes produced by the combustion of the coal are collected so as to weigh and sample them. After drying and determining the water the sample is put into a glass tube as with coal. As the quantity of hydrogen is usually very small, it need not be determined, and the calcination for the carbon can be performed in the open air. The following table contains the results of the tests made by Scheurer-Kestner and Meunier-Dollfus on steam-boiler cinders : Carbon. . . Hydrogen Ash f 2 3 9.20 0.37 89-95 12.65 0.29 86.50 6.73 0.21 92.64 99-52 99-44 99-58 8.92 0.27 91.42 99.61 The proportion of carbon in cinders may be as low as 7 per cent, but is usually higher, and 10 to 12 per cent may be called good practice. DURATION OF THE TEST. A test should continue at least a whole day on account of certain irregularities and causes of error which are constant. The level of the water should be the same at the end of the test as at the beginning, since a slight difference in level means considerable water. The condition of the combustion at the time of stopping cannot always be ascertained, and this produces a cause of uncertainty. Another cause is from the temperature of the water in the boiler, and especially in the economizer. On short runs these sources of error cause very faulty results. Il6 CALORIFIC POWER OF FUELS. THE WATER EVAPORATED. The feed-water is preferably held in a gauged reservoir, or else weighed, meters not being certain unless checked fre- quently. Use only cold water or water whose temperature will vary but little during the test, so as to avoid corrections of temperature and expansion. The temperature usually varies so little that no account of this variation need be taken. Pump to the boiler with as much regularity as possible, and keep accurate record. To have the same level at the end as at the beginning, keep up the initial pressure and feed very carefully. The mean temperature of the feed-water is referred to o° C, con- sidering that the specific heat is constant. Otherwise we may use Regnault's formula, Q — t — 0.00002/'' -|" 0.0000003/'. But when the temperature of the water varies no more than 10 degrees, no appreciable error will be made by calling / equal to the temperature. TEMPERATURE OF THE STEAM. We may measure the temperature of the steam directly by^ a thermometer in the boiler, or indirectly by observing the pressure. Both methods should be used. . To take the temperature directly, the thermometer is placed in an iron tube closed at one end and reaching to the middle of the boiler. The tube should be filled with parafifin or some analogous substance. The temperature of the steam or the water may be taken as desired by changing the position of the thermometer in the tube. See Figure 39. Vertical maximum and minimum thermometers are very use- ful, preventing too hasty observations. MOISTURE IN THE STEAM. H/ To measure the temperature by pressure an air-thermom- eter is used. A registering manometer aids the work consid- erably, as observations should be taken regularly at frequent and equal intervals. The temperature is calculated by means of tables of vapor-tension.* MOISTURE IN THE STEAM. The percentage of moisture should be ascertained by means of a throttling or a separating calorimeter, directions for the use of which will be furnished by the makers. They should easily and completely separate the water in a manner convenient for measuring, or better, for weighing. It is ad- visable to use two or three at the same time, thus serving as checks for each other. "The throttling steam-calorimeter was first described by Professor Peabody in the Trans actions, \ vol. X. page 327, and its modifications by Mr. Barrus, vol. XI. page 790; vol. XVII. page 617; and by Professor Carpenter, vol. Xll. page 840 ; also the separating-calorimeter designed by Professor Carpenter, vol. XVII. page 608. These instruments are used to determine the moisture existing in a small sample of steam taken from the steam-pipe, and give results, when properly handled, which may be accepted as accurate within 0.5 per cent (this percentage being computed on the total quantity of the steam) for the sample taken. The possible error of 0.5 per cent is the aggregate of the probable error of careful ob- servation, and of the errors due to inaccuracy of the pressure- gauges and thermometers; to radiation; and, in the case of the throttling-calorimeter, to the possible inaccuracy of the figure 0.48 for the specific heat of superheated steam, which * For full details regarding setting up an open-air manometer, see paper by Scheurer-Kestner and Meunier-Dollfus in the Bulletin de la Societe in- dustrielle de Mulhouse, 1869, page 241; also Trans. A. S. M. E., vol. vi. pages 281 and 282. f Transactions A. S. M. E. IIo CALORIFIC POWER OF FUELS. is used in computing the results. It is, however, by no means certain that the sample represents the average quality of the steam in the pipe from which the sample is taken. The prac- tical impossibility of obtaining an accurate sample, especially when the percentage of moisture exceeds two or three per cent, is shown in the two papers by Professor Jacobus in Transactions,'^ vol. XVI. pages 448, 10 17. *' In trials of the ordinary forms of horizontal shell and of water-tube boilers, in which there is a large disengaging sur- face, when the water-level is carried at least 10 inches below the level of the steam outlet, and when the water is not of a character to cause foaming, and when in the case of water- tube boilers the steam outlet is placed in the rear of the mid* die of the length of the water-drum, the maximum quantity of moisture in the steam rarely, if ever, exceeds two per* cent; and in such cases a sample taken with the precautions speci- fied in article xill. of the Code may be considered to be an accurate average sample of the steam furnished by the boiler, and its percentage of moisture as determined by the throttling or separating calorimeter may be considered as accurate within one half of one per cent. For scientific research, and in all cases in which there is reason to suspect that the moisture may exceed two per cent, a steam-separator should be placea in the steam-pipe, as near to the steam outlet of the boiler as convenient, well covered with felting, all the steam made by the boiler passing through it, and all the moisture caught by it carefully weighed after being cooled. A convenient method of 'obtaining the weight of the drip from the separator is to discharge it through a trap into a barrel of cold water stand- ing on a platform scale. A throttling or a separating calo- rimeter should be placed in the steam-pipe, just beyond the steam-separator, for the purpose of determining, by the sampling method, the small percentage of moisture which may still be in the steam after passing through the separator. *Transactions A. S. M. E. QUALITY OF STEAM. I I9 *' The formula for calculating the percentage of moisture when the throttling-calorimeter is used is the following: H- h- k{T-t) w = 100 X L in which w — percentage of moisture in the steam, 77= total heat and L — latent heat per pound of steam at the pressure in the steam-pipe, h = total heat per pound of steam at the pres' sure in the discharge side of the calorimeter, k = specific heat of superheated steam, 7"= temperature of the throttled and superheated steam in the calorimeter, and / = temperature due to the pressure in the discharge side of the calorimeter, = 212° Fahr. at atmospheric pressure. Taking /^ = 0.48 and / =: 212, the formula reduces to H— 1146.6 — 0.48(7— 212)* „ W = 100 X 7 • CORRECTIONS FOR QUALITY OF STEAM. f Given the percentage of moisture or number of degrees of superheating, it is desirable to develop formulae showing what we have termed ' ' the factor of correction for quality of steam, "" or the factor by which the ' ' apparent evaporation, " determined by a boiler-test, is to be multiplied to obtain the '' evaporation corrected for quality of steam." It has been customary to call the proportional weight of steam in a mixture of steam and water *'the quality of the steam," and it is not desirable to change this designation. The same term applies when the steam is superheated by employing the " equivalent evapora- tion," or that obtained by adding to the actual evaporation the * William Kent in the Report of the Committee on Boiler-tests, A. S. M. E.. i8g7. f C. E. Emery in the Report of Committee on Boiler-tests, A. S. M. E., 1897. I20 CALORIFIC POWER OF FUELS, proportional weight of water which the thermal value of the superheating would evaporate into dry steam from and at the temperature due to the pressure. ''The factor of correction for quality of steam " in a boiler-test differs from the ' ' quality " itself, from the fact that the temperature of the feed-water is lower than that of the steam. Let Q zzz quality of moist steam as described above ; Q^ = the quality of superheated steam as described above ; P = the proportion of moisture in the steam ; J^ = the number of degrees of superheating; F= the factor of correction for the quality of the steam when the steam is moist • /^i = the factor of correction for the quality of the steam when the steam is superheated ; H =z the total heat of the steam due to the steam-pressure; L = the latent heat of the steam due to the steam-pressure ; T = the temperature of the steam due to the steam-pressure ; 7", =z the total heat in the water at the temperature due to the steam-pressure;^^ y =z the temperature of the feed- water; y, = the total heat in the feed-water due to the temperature.* Therefore, for moist sceam, Q=i-P, (I) P= 1 - Q (2) Q + P=i (3) See also equation (6). * Most tables of the properties of steam and of water are based on the total heat of steam and water above 32 degrees Fahr. For such tables the total heat in the water at a given temperature is equal approximately to the corresponding temperature minus 32 degrees. Exact values should, however, be taken from the tables. QUALITY OF STEAM. 121 With both the condensing and throttling calorimeters the Avater and steam are withdrawn from the boiler at the temper- ature of the steam, and with a separator the water can only be accurately measured when underpressure, so that the difference l)etween the steam and the moisture in the steam, as they leave the boiler, is simply that the former has received the latent heat due to the pressure, and the latter has not. There is, however, imparted to the water in the boiler not only the latent heat in the portion evaporated, but the sensible heat due to raising the temperature of all the water from that of the feed -water to that of the steam due to the pressure. In equation (3) the proporti6nal part Q receives from the boiler both the sensible and the latent heat, or the total heat above the temperature of the feed = Q(^H — J^ thermal units, and the part Pthe difference in sensible heat betw^een the tem- peratures of the steam and of the feed-water ~ P[T^ — J^ thermal units. If all the water were evaporated, each pound would receive the total heat in the steam above the tempera- ture of the feed, ov H — J^. '* The factor of correction for the quality of the steam," when there is no superheating, is therefore P- . //_/. -Q + ^Kh^j} ■ (4) The superheating of the steam requires 0.48 of a thermal unit for each degree the temperature of the steam is raised, ^o for k degrees of superheating there will be 0.48/^ thermal -anits per pound weight of steam, and the '* factor of correc- tion for the quality of the steam " with superheating. //-/, + 0.48^ o.4ik ^' = — w^j, — = ' + H:rr- • • (5) See also equation (7). 122 CALORIFIC POWER OF FUELS. With the throtthng-calorimeter the percentage of moisture P, or number of degrees of superheating, are determined as explained before. Since the invention of the throttling-calorimeter the use of the original condensing, or so-ealled barrel, calorimeter is no longer warranted. Accurate results should, however, be obtained by condensing all the steam generated in the boiler, and this plan has been followed in certain cases. It has, therefore, been thought desirable to add other formulae ap- plicable to condensing-calorimeters. The following additional notation is required -. W =i the original weight of the water in calorimeter, or weight of circulating water for a surface condenser. w = the weight of water added to the calorimeter by blow- ing steam into the water, or of " water of condensation " with a surface condenser. / = total heat of water corresponding to initial tempera- ture of water in calorimeter. /j = total heat of water corresponding to final temperature in calorimeter. Evidently, then : W{t^ — /) = the total thermal units withdrawn from the boiler and imparted to the water in calorimeter. W — it — /) = the thermal units per pound of water with- w drawn from the boiler and imparted to the water in calorim- eter, from which should be deducted T, — /, to obtain the number of thermal units per pound of water withdrawn from the boiler at the pressure due to the temperature T. Since only the latent heat L is imparted to the portion of the water evaporated, the quality Q, or proportional quantity evaporated, may be obtained by dividing the total thermal units per pound of water abstracted at the pressure due to the temperature T by the latent heat L. Hence, as given in QUALITY OF SUPERHEATED STEAM. 12$ Appendix XVII., 1885 Code, with some differences in nota- tion, aanda = 2[^(^.-0-(r, -A)]. . . (6) The value Q applies when the second term is less than unity. P may be derived therefrom by substitution in equa- tion (2) and F from equation (4). Q^ applies when the second term of the above equation is greater than unity, which shows that the steam is superheated, and, as in this case, the heating value of the superheat has already been measured by heating the water of the calorim- eter; the proportional thermal value of the same, in terms of the latent heat Z, is represented directly by Q^ — i, and we have as the factor of correction for the quality of the steam with superheating, See also equation (5). When the quality is greater than i, or equals Q^ , the num- ber of degrees of superheating, ^= ^^i[^'^ ~^-oSi3L{Q.-i)- . ■ (8) THE QUALITY OF SUPERHEATED STEAM. ^ The quality of the superheated steam is determined from the number of degrees of superheating by using the following formula : _ Z + o.48(r-^) ^~ L * G. H. Barrus in Report of Committee on Boiler-tests, A. S. M. E., 1897. 124 CALORIFIC POWER OF FUELS. in which L is the latent heat in British thermal units in one pound of steam of the observed pressure ; T the observed temperature, and / the normal temperature due to the pres- sure. This normal temperature should be determined by ob- taining a reading of the thermometer when the fires are in a dead condition and the superheat has disappeared. This tem- perature being observed when the pressure as shown by the gauge is the average of the readings taken during the trial, observations being made by the same instrument, errors of gauge or thermometer are practically eliminated. DETERMINATION OF THE MOISTURE IN STEAM FLOWING THROUGH A HORIZONTAL PIPE.* In some cases it is impossible to place the sampling nozzle in a vertical steam-pipe rising from the boiler as recommended in Article XIV. of the Rules for Steam- boiler Trials. t When this is the case and it is possible to connect to a horizontal steam-pipe the arrangement of throttling calorimeters shown in Fig. 2'jg gives satisfactory results. The calorimeter A is attached to the separator G^ which is in turn attached to the under side of the steam-pipe by the nipple D, The nipple D is made flush with the bottom of the pipe. The calorimeter B is attached to a nozzle having no side holes, which passes through the stuffing-box E. This nozzle is adjustable so that the steam can be drawn from any height in the pipe. When in its lowest position it is flush with the bottom of the pipe. The calorimeter C is attached to the perforated nipple F, The calorimeters are placed at some distance from an elbow or bend, so that if there is moisture in the steam it tends to run along the bottom of the * By Prof. D. S. Jacobus. f See page i86. DETERMINATION OF THE MOISTURE IN STEAM. 124a pipe. This moisture will flow into the nipple I) and collect in the separator G. Nearly all the moisture may sometimes \ P§^ be drawn out in this way, and if the calorimeters B and C in- dicate dry steam, the weight of moisture collected in G rep- resents the entire moisture in the steam. The three calorim- eters are all covered in the same way to diminish radiation, and the normal reading of the thermometers / and y used in the calorimeters B and C can ordinarily be obtained by plac- I24<^ CALORIFIC POWER OF FUELS. ing them in the calorimeter A. The perforated nipple F serves to show that there is no moisture distributed through the steam, and in the case of a sudden belch of moisture it will indicate the same. Barrus calorimeters were used in our tests, and the calorimeter A, combined with the separator Gy forms in reality a Barrus Universal Calorimeter. With a properly constructed separator, the steam passing through the calorimeter A will be practically dry with as high as sixty pounds of moisture drawn from the separator per hour, and, until this limit is exceeded, the normal readings of the ther- mometers used in the calorimeters B and C may be obtained by placing them in the calorimeter A^ as has already been stated. In some cases the calorimeter C is omitted and the amount of moisture is determined by means of the separator, with the adjustable nozzle at E and the separator and calo- rimeter A. The percentage of priming P iox the steam passing through the calorimeters B and C is given by the formula P = ^(i\^- 2), where P = the percentage of priming; N = the normal reading, in degrees Fahrenheit, ob- tained placing the thermometers in A ; T = the reading when placed in either B ox C \ L ■= the latent heat at the pressure of the steam in the steam main in British thermal units per pound. It is best to employ the normal reading in calcula- ting the moisture corresponding to the readings of a throt- DETERMINATION OF THE MOISTURE IN STEAM, I24C tling calorimeter. The radiation of the calorimeter must also be determined by a separate experiment, and allowed for. When the normal reading is taken all errors of radiation and corrections for the thermometers are elimi- nated. The normal reading should be obtained either by connect- ing the calorimeter to a vertical nipple, with no side holes, which projects upward in a horizontal steam-pipe, in which the steam is in a quiescent state, or it should be obtained by connecting the calorimeter to a separator, which is known to remove all the moisture. The normal reading should not be determined when the calorimeter is attached to a horizontal nipple with side holes, placed in a vertical pipe, because should this be done the readings may be low on account of moisture, which may fall through the steam and cling to the nozzle, and, finally, be drawn into the calorimeter. The results given by a throttling calorimeter cannot be relied on within one-fifth of one per cent, because experi- ments have shown that the quality of the "dead steam" used in obtaining the normal readings may vary by this amount."^ As the quality of the ''dead steam" may not be that of the steam used by Regnault in his experiments, there may be a still greater error. When the formula given on page 119 is used the probable error is not eli- minated, for a study of Regnault's experiments shows that the value used in the formula for the specific heat of superheated steam may be slightly in error for the con- ditions involved in a throttling calorimeter. Experiments have shown that the two methods of computing the moisture agree within one-fifth of one per cent when the proper corrections are made for radiation, and when the * Transactions American Society of Mechanical Engineers, vol. xvi. p. 466. 124^ CALORIFIC POWER OF FUELS. temperatures are reduced to the equivalents by an air thermometer.^ These experiments were made at the single pressure of 80 lbs. per square inch above the atmos- phere, and it has not been shown that the two methods agree within this amount at all pressures, but as there should be no discrepancy provided the specific heat factor remains constant for the conditions involved, it is probable that the two methods agree very nearly with each other at all pressures.! What is needed are tests to compare the quality of **dead steam "with the quality of the steam used in Regnault's experiments, and until this is done throttling- calorimeter results cannot be relied upon within one-fifth of one per cent, and may be in greater error than this amount. COMBINED CALORIMETER AND SEPARATOR.;}: The form of steam-calorimeter termed the '' 1895 pat- tern " or universal steam-calorimeter is a modification of the one described in the Transactions Am. Soc. Mech. Eng., vol. XI. page 790. It is illustrated in the accompany- ing cut, which is reprinted from vol. XVII. page 618, of the same Transactions. It consists of a throttling calorimeter and separator combined, the latter being attached to the outlet where the steam of atmospheric pressure is escap- ing. If the moisture is too great to be determined by the * Transactions American Society of Mechanical Engineers, vol. xvi. p. 460. f It must not be inferred from this that the specific heat of steam is the same at all pressures. On the contrary. Jacobus's experiments show that this is not the case. :f By George H. Barrus. COMBINED CALORIMETER AND SEPARATOR. I24e readings of the two thermometers, the separator catches the balance, and the total quantity of moisture is made ieOw Fig. 27>^. — Combined Calorimeter and Separator. up in part of that shown by the thermometers, and in part of that collected from 'the separator. The percentage of moisture shown by the thermometers is obtained by refer- ring the indication of the lower thermometer to the normal reading of that thermometer with dry steam, and dividing the fall of temperature by the constant of the instrument for one per cent of moisture. The normal reading is determined by observing the indications when steam in the main pipe is in a quiescent state, and the constant is a quantity varying from 2i degrees at 80 pounds pressure to 20 degrees at 200 pounds pressure. The percentage of 124/ CALORIFIC POWER OF FUELS. moisture, if any, discharged from the separator, is found by dividing its quantity corrected for radiation by the total quantity of steam and water passing through the instru- ment in the same time, as ascertained by experiment, and multiplying the result by lOO. CHAPTER XL AIR SUPI?.LIED AND GASEOUS PRODUCTS OF COM- BUSTION. VOLUME OF AIR NECESSARY TO COMBUSTION. Four elements are to be considered in calculating the theoretical volume of air for combustion: carbon, hydrogen, oxygen, sulphur. The last is sometimes wanting in coal, but not usually. Carbon. — The atomic weights of carbon and oxygen are as 12 and i6, and 2 atoms of oxygen are needed to form car- bonic acid with i atom of carbon. Then 12 : 32 = I : 2.666. I kilogram of oxygen occupies 0.699 cubic metre (Table IV); I kilogram of carbon needs 0.699 X 2.666 — 1.863 cubic metres of oxygen. Hydrogen. — The atomic weights of hydrogen and oxygen 'being respectively i and 16, and water being formed of 2 atoms of hydrogen and i of oxygen, we have 2 : 16 = I : 8; and as i kilogram of oxygen occupies 0.699 cubic metre, i Icilogram of hydrogen requires 8 X 0.699 = 5-592 cubic metres of oxygen. 125 126 CALORIFIC POWER OF FUELS. Sulphur. — The atomic weights of sulphur and oxygen being as 32 to 16, and sulphurous acid containing I atom of sulphur and 2 atoms of oxygen, we have 32 : 32 = I : I. I kilogram of oxygen occupies 0.699 cubic metre; I kilo> gram of sulphur needs, then, to form sulphurous acid I X 0.699 — 0-699 cubic metre of oxygen. As most fuels have some oxygen in their composition, we must deduct this at the rate of 0.699 cubic metre per kilo- gram. Then multiplying these results by 4.77 (Table XIV) we obtain the number of cubic metres of air required. A simifar method of calculation will give For one pound of carbon 29.86 cubic feet of oxygen* " hydrogen 89.60 '' " '* " sulphur 11.20 " '' " As an example, take a coal containing 90^ C, 5^ H, 3-5/^ O, o.iio N, and 0.5^ S. C 0.900 X 1.863 = 1.677 cubic metres. H 0.040X5.592=0.224 S 0.005 X 0.699 — 0.003 Total oxygen i .904 O . . . .0.035 X 0.699 — 0.024 1.880 1.880 X 4.77 = 8.967 cubic metres of air per kilogram of coal; or 143.98 cubic feet of air to the pound of coal. This result of course is only approximate, as complete combustion is not attained with coal and solid fuels. With liquid fuels, and especially gases, however, the combustion is usually complete. VOLUME CF WASTE CASES BY ANALYSIS. 12/ Tables V and VI gives the coefficients to be employed in the calculations. Table XIII gives the theoretical quantity of air required for the combustion of various fuels; the actual quantity used depends on the conditions of firing, fuel, etc, and is seldom less than twice the amount shown in the table, except perhaps with gases. VOLUME OF WASTE GASES BY ANALYSIS. For a long time efforts have been made to determine the quantity of air used by comparison of the analyses of the waste gases with those of the fuel used. Many analyses have been published, but the results showed so little regu- larity, and were so contradictory even, that it was impossible to form any conclusion further than that waste gases from coal may contain at the same time both combustible gas and an excess of air. Peclet, in 1827, published the first analyses, made with samples collected from a boiler-stack by means of an inverted flask containing water. Ebelmen, in 1844, published a memoir on the composition of gases from industrial furnaces. He analyzed the gases from a metallurgical furnace, the gas being collected by an aspirator. In 1847 Combes made a report on methods of burning or preventing smoke, giving analyses by Debette. In these the first attempts were made to obtain average samples, they being drawn at certain deter- mined stages of the heat and the fuel. In 1862 Commines de Marcilly published analyses of gases from locomotives, as well as from stationary boilers, but the author said the time of collection lasted only a few seconds. In 1866 Cailletet showed that, to obtain correct results, the gas should not be collected till somewhat cooled ; otherwise, on account of dissociation, a larger proportion of combustible gas is found than when cooler. But, on account of the defective methods of sampling 128 CALORIFIC POWER OF FUELS. used, no conclusion other than that stated above can be drawn from these analyses, and no possible idea can be deduced as to the actual composition of the gases as a whole. When we try to use laboratory methods of control in practi- cal workings, the first necessity is to obtain correct samples for analysis, that is, average samples. In this respect all the above -quoted authors are deficient. The tests made by Scheurer-Kestner, published in 1868, were the first to con- form to this requirement. His samples were drawn by a system analogous in principle to that described for sampling coal. It is not always necessary to resort to such a complicated operation in case of a permanent gas; samples taken from the general current by means of an ordinary aspirator or an oil-aspirator (page 132) will usually do if drawn at a sufficient distance from the fire. If the gases have passed through a long flue, especially one with several bends, they are suffi- ciently mixed, and may be considered as a homogeneous gas. We must remember, however, that as we recede from the fire the infiltration of air, if not prevented, becomes greater. In careful experiments, the method to be described of frac- tionating a large volume is preferable. GAS SAMPLER. In principle the apparatus consists of a falling-water aspirator, and a second mercury aspirator drawing a small fraction of the gases from the current of the first in a con- stant regular manner and keeping it in a mercury gas-holder, A (Fig. 28), which is a strong glass flask of 3 litres capacity, holding about 40 kilograms (88 lbs.) of mercury. The gas-holder is connected by the tube a with the tube c for sampling the gas, the flask A and its accessories acting as a Mariotte flask. It is closed at the top by a stopper hollowed out conically below and having holes for two tubes, a and b. This hollowing is to permit filling without GAS SAM FLEE. 129 any air-bubbles. The tubes a and b have glass stop-cocks, but the one in a may be omitted. The manometric tube c shows the pressure. Tube d, like c, passes through a rubber stopper, closing the horizontal tubulature of the gas-holder. ;^ '^ i/t ■MM Fig. 28. — Gas Sampler. fl Fig. 29. — Sampler Tube. This tube can be rotated in the stopper to the position shown, or to one 180° from such position. The flask is graduated on the side into millimetres. Tube a fits the hole of the stopper tightly, and can be moved up or down as desired to suit the quantity of gas in the flask. All joints are covered with paraffin, tube a being greased to facilitate movement. Fig. 29 shows the gas sampling tube. It consists of a platinum cylinder, rs, 10 millimetres (0.4 inch) diameter and 700 millimetres (27.5 inches) long, having a longitudinal slot of several centimetres length. The end r is closed with a 130 CALORIFIC POWER OF FUELS. platinum cap; the end s is soldered to a copper tube, j/, pass- ing into a Liebig condenser having two tubes, oo\ for the water. In most cases the platinum tube may be replaced without trouble by one of copper, or even iron, the platinum being necessary only when the gases are drawn at a tempera- perature high enough to cause oxidation of the other metals. With iron, or copper a portion of the oxygen is removed in the passage through the tube. The tube ry is open at/, and has a side tube Ji. Aspira- tion is carried on through the opening in the platinum tube. A movable rod, ik, carrying a platinum scraper is attached to one end of the tube, and moves in the slot to clean it, as occasion requires, from soot, etc. The disk/) serves to hold the cement used in fastening it to the stack or chimney, and pre- vents ingress of external air. The rod mn passes through a caoutchouc bearing fastened between the disks/ and q. Fig. 28 represents a front view of the apparatus. Fig. 30 represents a side view in elevation. The tube ry is intro- duced through an opening made for the purpose in the masonry, the pait rs being exposed inside. The end y, is connected with a lead pipe, v, by a rubber tube ; this pipe is soldered to another one, yz. On opening the cock j, water flows from a reservoir and empties at z. Suction in yrs should amount to several millimetres of mercury, and is regu- lated by the cocks j/ and x controlling the water-flow, and also by the length oi yz. The gas drawn in by yux may be meas- ured by collecting it at z, and should amount to 4 or 5 litres (25 to 30 cubic inches) per minute. The gas-holder is supported by a piece of sheet iron with upturned edges forming a shelf. Any mercury spattered over or spilled is thus easily collected. The mercury tank is supported from the w^all of the chimney in such position as to facilitate refilling the flask through a siphon. The tubes dd' serve to feed the condenser. While the current is passing through yr a small quantity GAS SAMPLER. 131 IS drawn out by the tube //, and this should be so regulated by the cock d that only from ^-^ to -^^-^ is collected. Whenever the level of the mercury lowers, it shows a 7t> Fig. 30. — Gas Sampler. clogging in the slot, and it should be cleaned by moving the rod. This always indicates when cleaning is necessary, and it sometimes keeps clean for hours. When a sufficient sample has been obtained turn up the tube dj and then the gas-holder can be carried away. The method recommended by the American Society of Mechanical Engineers is to have a *'box or block of gal- vanized sheet iron equal in thickness to one course of brick,'* and secure in it a series of J-inch gas-pipes, all alike at the ends and of equal lengths, in such manner that the open ends may be evenly distributed over the area of the flue A (Fig. 32), and their other open ends enclosed in the receiver B. 132 CALORIFIC POWER OF FUELS. A simpler arrangement than Scheurer-Kestner's is the one recommended by Col. David P. Jones in his paper before the American Society of Naval Engineers, vol. X. page 135. The sampler is a large, wide-necked glass bottle (Fig. 30^), closed with a cork having two glass tubes, one just entering the bottle, the other reaching nearly to the bottom. One of these tubes is connected with an iron pipe leading to the flue and extending well into it. The other tube is connected with any kind of an aspirator which works steadily. A water-jet exhaust, an engine-driven ex- haust, or any similar kind will do. If not convenient to use an exhaust, the bottle may be filled with mercury and by mak- ing a siphon with the rubber tube attached to the long glass tube, the bottle can be gradually emptied of mercury and the gases to be sampled drawn in. If mer- cury cannot be had, water will do, but the result will not be as reliable since the water may dissolve some of the constitu- ents of the gas. The size of the bottle may be adapted to the quantity of gas aspirated, and by means of proper stop- or pinch-cocks adjusted to work slow or fast. Used in conjunction with the arrangement figured on page 134 this apparatus forms a very simple and satisfactory sampler. One great advantage in favor of this arrangement is the fact that it is easily made, all the portions of it being; found in nearly every shop. Fig. 30a. — Jones Gas Sampler. GAS SAMPLER. 13^ Fig. 31. — Oil Aspirator. If the flue-gases be drawn off from the receiver B hy four tubes, CC, into a mixing-box, D, beneath, a good mixture can be obtained. Two such samplers, one above the other, a foot apart, in the same flue will furnish samples of gases which show the same compo- sition by analysis. The oil gas holder (Fig. 31) con- sists of a bottle tubulated at the bottom and connected with the sup- ply of gas at the upper opening. It may contain some 10 litres (600 cubic inches), and is filled with water having on it a layer of lO centimetres (4 inches) of oil. The water running out from the tubu- lature at the bottom draws the gas in at the top. The stopper at the top has two openings, through one of which passes a funnel-tube, through which water may be poured to expel the gas when portions of it are needed. The gas then passes out by the same tube through which it was drawn into the bottle. With all kinds of aspirators or gas holders especial care must be taken to prevent entrance of air into the flue after leaving the fire, since the correct analysis will show not only the quantity of unburnt gases, but also the excess of air, and any mixture of outside air will vitiate the result and cause faulty deductions as to the working of the fire; and conse- quently the waste calories. To prevent this, all joints in the masonry must be exam- ined and repaired if necessary. In case of dampers, which must be used, the bearings can be made in stufling-boxes, as. recommended by Burnet. Generally, the gas can be sampled before it arrives at a damper, as the course of the boiler-flue 1 34 CALORIFIC POWER OF FUELS. is usually sufficient to cause a thorough mixing of the gases. In case there are several dampers, the first one may be dis- pensed with for the time being. When the gases are taken quite near the fire, they must be drawn very slowly in order to gradually cool them down and ^vx^-^ Fig. 32, avoid dissociation. In this case a stoneware tube may be used for suction. If this precaution is neglected the gases collected may be entirely different from those passing off at the chimney. Metal tubes are inadmissible, since they abstract oxygen, and hence cause a change in composition. ANALYSIS OF THE GASES. The collected gases contain nitrogen, oxygen, carbonic acid, carbonic oxide, hydrocarbons, and occasionally free hydrogen. To determine all these a eudiometric method GAS SAMPLER. 135 must be used ; but usually only the oxygen, carbonic oxide, and carbonic acid are required. In normal combustion with sufficient air the quantity of hydrocarbons is very trifling, and need not be considered. This occurs usually with a supply of 15 cubic metres of air per kilogram (240 cubic feet per pound) of coal, and should produce a waste gas containing 10 to 14 per cent of carbonic acid, in which case the unburnt hydrocarbons amount to less than i per cent. The Orsat apparatus or its modifications may be used to determine the oxygen, carbonic acid, and carbonic oxide. By using Winckler's modification the hydrocarbons may be deter- mined. For exact analyses of the gases the Hempel apparatus may be used. For general work, however, the Orsat appa- ratus or the Orsat-Muencke is the best and most easily transported and handled. Directions for using this apparatus need not be given here, as they can be found in all works on gas analysis, or can be had of the dealers. The following table gives analyses made by Scheurer- Kestner of waste gases from Ronchamp coal. The gases for examination were collected by means of the apparatus described above (pp. 128 ^/ seq.) and shows the average for a whole dav's run. Percentage Composition of the Gases. a a x: U "o bo ■a < 1 C >, X 4J •a >< 5 1 U Hydrocarbons. c < c ■a X c V - [1. 6.60 10.47 13-32 17.61 20.94 26.18 42. 84 53-78 80.38 80.60 80.66 81.52 80.23 80.34 79.76 79-86 14.87 14.16 14.63 13-34 13-43 12.89 10.87 8..3 1. 41 2.18 2.80 3-77 4.42 5-53 8.99 11-35 0.84 0.97 0.86 0.86 0.24 0.24 0.24 0.24 0.98 0.49 0.46 0.32 0.28 0.19 0.04 1-35 I. II 0.56 0.91 1. 41 0.96 0.19 0.52 Lbs. 8.19 9.625 9-625 8.19 8.19 4.71 18.94 3-41 Lbs. 15-4 30.8 15.4 15-4 30.8 15-4 15-4 13-2 4 3' 2' 10' 136 CALORIFIC POWER OF FUELS. The following table gives some analyses by Bunte of gas samples from coal burnt in his experimental apparatus at Munich : Mm. and Max. CO, CO H N of Air. Coal from the Ruhr 10.26 0.53 1-94 0.48 1.22 O.OI 10.00 79-20 78.64 79-30 79.28 80.14 Do. 16.45 13.40 11-45 8.15 1-45 0.30 0.78 O.OI 1.52 6.52 7.27 11.60 Do. Do. Do. (grate more open). O.IO Do. Do. 6.12 0.89 O.IO 14.21 78.68 Coal from Saarbruck: Koenig.. S Min. " ■ Max. 15-12 1.09 1.02 2.64 80.13 7.07 0.18 0.00 12.57 80.25 *' " Tr^mosna: Bohemia j Min. ■ Max. 13-78 4.69 0.16 1. 10 80.27 7-94 0.03 0.09 11.03 80.91 " " Hausham: Bavaria. Min. ] Max. 10.48 0.07 0.19 9.28 79.98 5.71 0.14 0.08 14.86 79.21 " " Miesbach: Bavaria. Min. Max. 11.46 0.07 0.07 8.66 79-74 5 42 0.03 0.02 I5-00 79-53 *' *' Bohemia \ Min. ] Max. 17.48 12.20 I. 21 0.06 0.30 3-13 7-87 78.12 ? " " the Ruhr : General j Min. / Max. 16.45 1.94 1-45 1.52 78.64 Erbstolln 3 95 0.06 0.00 16.41 79-58 " the Ruhr : Gelsen- J Min. 1 Max. j Min. 1 Max. j Min. \ Max. 10.46 O.I I O.II 8.58 80.74 kirchen 5.44 10.73 0. 12 0. 10 14.15 7.36 80.19 81.46 « ** " Saarbruck : Saint- 0.15 0.30 Insfbert. ><....... 7.48 13-30 0.07 0.61 0. lO II. 91 4-13 80.44 81.63 •• " Saarbruck : Mittel- 0.33 bexbach 8.44 0.19 0.16 10.58 80.6s " '• Saarbruck : Heinitz j Min. \ Max. 14.62 6.49 2 07 0.07 1. 00 0.06 2.07 12.70 80.24 80.68 " ** Saarbruck: mixed.. j Min. / Max. 10.22 0.22 0.07 8-57 80.92 8.21 0.04 0.02 10.64 81.09 " '• Bohemia j Min. ■j Max. 15-50 8.48 0.74 0.08 0.33 0.07 1.67 9.69 81.66 81.68 «( (( j Min. \ Max. 9.61 7.00 0.16 O.II 0.08 0.05 9-47 12.70 80.68 80.14 " " Saxony j Min. ■j Max. 13-S0 7.60 0.33 0.16 0.30 0.09 4-36 11.53 81.21 80.62 " •• Silesia j Min. "j Max. II. 4 8.07 15 O.IO 0.04 0.09 7.45 10.73 81.22 81.01 " *' Bavaria : Peissen- j Min. \ Max. j Min. { Max. 13.96 1.46 0.79 2-93 80.86 berfif 7-85 14.91 6.36 0.07 1.04 0.16 0.13 0.60 0.23 10.57 2.92 13.15 81.38 80.53 80.10 ^^'s • Lignite from Bohemia Coke from Saarbruck j Min. ]Max. 14.87 8.01 0.13 0.03 0.09 0.00 4.16 10.87 80.75 81.09 The data in the above table show that when air to the amount of 15 cubic metres and over per kilogram (200 cubic CALCULATIOy OF THE VOLUME FROM A.N A LYSIS. 13/ feet per pound) is used, corresponding to a maximum of 14 per cent of carbonic acid in the waste gases, the loss in hydro- gen is very small. With 12 per cent of carbonic acid the hydrogen loss amounts to only a few thousandths. CALCULATION OF THE VOLUME FROM ANALYSIS. To calculate this volume, determine the weight of carbon in a unit of volume, and knowing the weight of carbon fur- nished by the coal, determine the volume corresponding to the unit of weight. The unit of volume for the gas is the cubic metre, and the unit of weight, the kilogram. Carbon exists in the waste gases as carbonic acid, carbonic oxide, and hydrocarbons; when we do not know the compo- sition of the hydrocarbons, we consider the carbon and hydro- gen as free, and that the carbon is in the state of vapor. To determine the weight of carbon contained in these different gases, reduce their volumes to kilograms, and by means of their molecular (or equivalent) weights and that of carbon make the calculation. I litre of CO2 at 0° and 760 mm. weighs 1.966 grams. I " '' CO " '' " '' '* '' 1. 251 ** I '* '' C vapor *' '' " 1.072 Molecular weight of carbon 12 '' '' CO, 44 '' '' CO 28 The weight of a volume v of carbonic acid is z/ X 1.966, and as 44 of carbonic acid contain 12 of carbon, then the weight of carbon would be as 44 : 12 or as 1 1 : 3. Then V X 1.966 X 3 . ^ -^ = 0.536Z;. 138 CALORIFIC POWER OF FUELS. The weight of carbonic oxide of volume v is 1.2512^', and as 28 of carbonic oxide contains 12 of carbon, the ratio be- comes 28: 12 = 7:3. We then have = 0.5362^. 7 The weight of a volume of carbon vapor is v" X 1.072. To calculate the weight of carbon in a cubic metre of gas. multiply the added volumes of CO, and CO by the coefficient 0.536. Multiply the volume of carbon vapor by 1.072, and add this product to that obtained above. The sum is the weight of carbon per cubic metre, C — 0.536(2^ + v) + 1.0722/". If the gas contains, per cubic metre, 60 litres of carbonic acid, 10 of carbonic oxide, and i of carbon vapor, we will have c = 0.536(60 + 10) + 1.072 X I — 38.592 grams carbon. From the ratio of carbon of the coal consumed and that in the gas the volume of combustion gases is deduced. To calculate this, subtract the carbon of the cinders from that of the original coal. If the coal contains 81 per cent carbon and leaves 6 percent of cinders containing 10 percent of carbon, then the amount of carbon burnt will be 81 — (o.io X 6.0) = 81 — 0.6 = 80.4. We then have 38.592 : 1000 = 804: 20.830 litres. A kilogram of coal produces, then, 20.83 cubic metres of gas at 0° and 760 mm. The general formula is C-c V = {v -\- v')o.^-^6 -\- 1.0722;'" CALCULATION OF THE VOLUME FROM ANALYSIS, 1 39 in which y = volume of waste gases at o° and 760 mm. in cubic metres; 7^ z= " '' CO3 in litres per cubic metre of gases; -.' <( **CO'' *^ *' '* '* '* *' 2^''= '' '* carbon vapor per cubic metre of gases ; (7 = weight of carbon in grams, contained in i kilogram of coal; c = weight of carbon in grams, contained in cinders from i kilogram of coal. Note. — The above calculation in English units would be as follows: Weight of I cubic foot of carbonic acid o. 12274 lb. *' " I " " " " oxide 0.07811 " " «t J «' •« .i carbon vapor 0.06693 ** V X 0.12274 X 3 = 0.03352/. v' X 0.0781 1 X 3 ■ = 0.0335Z/ . 7 0.066932/' = weight of carbon in vapor. C =: 0.0335(2/ -f- ^') + 0-066932/". 1000 cubic feet of gases having 60 cubic feet of COa , 10 cubic feet of CO and I cubic foot of C vapor would give C = 0.0335(60 -f 10) + 0.06693 X I = 2.412 lbs. carbon. I pound of coal has 80.4 per cent carbon; then 2.412 : 1000 =0.804 : 333i cubic feet of gases produced from i lb. of coaL The general formula is v = 00335(2/ -f- 2/') -|- 0.066932/"' in which F = volume in cubic feet of gases produced; V = " of CO2 in cubic feet per 1000 cubic feet; v' = " " CO " " " " v" = " " carbon vapor in cubic feet per 1000 cubic feet; C = weight of carbon in coal in thousandths of a pound; c — " " " " cinders per pound of coal in thousandths. 340 CALORIFIC POWER OF FUELS. CALCULATION OF VOLUME OF AIR SUPPLIED. The volume of combustion-gases just determined is less than that of the air supplied. Oxygen in forming carbonic acid produces a volume equal to itself; hence there is no change. C + O, = CO, 2 vols. 2 vols. Oxygen in forming carbonic oxide produces twice the volume. C + O = CO I vol. 2 vols. Hence there is an increase in volume. Carbon vapor and hydrogen as free gases or as hydro- carbons increase the volume but slightly. In forming sul- phurous acid with sulphur there is no change of volume. S + 0, = SO, 2 vols. 2 vols. Another slight cause of increase is setting free the nitrogen of the coal ; but this is inappreciable. i per cent of nitrogen forms only o. i per cent of the entire volume of gases formed. It might be said that, excepting the oxygen changing to water and disappearing by condensation, all the modifications of gaseous volume may be neglected, the increase being more than compensated by the loss due to oxygen. This elimina- tion of oxygen must be allowed for, however. A coal containing 4 per cent of hj^drogen requires eight times such weight to form water, or 40 grams of hydrogen need 320 grams of oxygen. i litre of oxygen weighs 1.430 grams, then 320 grams measure ^^^^ =^ 223.7 litres (7.9 cubic feet). (Or i lb. of such coal would need 3.6 cubic feet of oxygen.) These 223 litres, must be added to the volume of the waste gases produced by the coal to obtain the original CALCULATION OF VOLUME OF AIR SUPPLIED. I4I volume of air introduced. A coal containing 5 per cent of hydrogen would use 279 litres. The volume of oxygen needed for various percentages of hydrogen is as follows : Per kilo of coal. Per lb. of coal. \(fo hydrogen uses of oxygen 55.9 litres, 0.9 cubic feet. 2 '' " *' 112 *' 1.8 '' 3 '<■ " " 168 '' 2, J '' " 4 c, i( a 223 *' 3.6 '' 5 '' '' " 279 '' 4.5 '' '' Calling H the per cent of hydrogen, the formula given above becomes '^' - {v + v')o.s63+ 1.071^/^^ + 55.9 H, or C-c' y = 7 i TTH Z2 77 + O.Q H. o.0335(z/+z/) + o.o6693^'^' ' ^ To make this applicable to normal air saturated with moisture at 0° C. and 760 mm. (32° F. and 29.922 inches) containing 0.4 per cent of CO^, we must divide by 99.12, the composition of air being: Nitrogen 78-35 Oxygen 20. 77 Water , ,... 0.84 ^ , . ., , 0.88 Carbonic acid , 0.04 100.00 And 100 — 0.88 = 99. 12. The formula then becomes C-c' \v or ^" - ' 4- 2/O0.567 + \,Q%Q(iv" + 5 5-9 H, ^ ' ~ 0.0337(2/ + v') + o.o6752z/'^ + °'^ ^- 14- CALORIFIC POWER OF FUELS. CALCULATION OF WEIGHT OF WASTE GASES FROM ANALYSIS.* Two methods of calculating from the analysis by volume of the dry chimney gases the number of pounds of dry chim- ney gases per pound of carbon, or the weight of air supplied per pound of carbon, have been given by different writers. These may be expressed in the shape of formulae as follows: /AX -p A A AT iiCO,+ 80 + 7(0+N) (A) Pounds dry gas per pound C = —^ ■ • ^ y^ P P 3(CO,+ CO) (B) Pounds air per pound C = 5.8 ^^^^^+^^+ -^. Formula A may be derived from the method of computa- tion given in Mr. R. S. Hale's paper on " Flue Gas Anal- yses," Transactions A. S. M. E., vol. XVIII. p. 901, and formula B from the method given in Peabody and Miller's Treatise on Steam-boilers. Both are based on the principle that the density, relatively to hydrogen, of an elementary gas (O and N) is proportional to its atomic weight, and that of a compound gas (CO and CO^) to one half its molecular weight. Both formulae are very nearly accurate when pure carbon is the fuel burned ; but formula B is inaccurate when the fuel contains hydrogen, for the reason that that portion of the oxygen of the air-supply which is required to burn the hydrogen is contained in the chimney gas as H^O, and does not appear in the analysis of the dry gas. The following calculations of a supposed case of combus- tion of hydrogenous fuel illustrates the accuracy of formula A and the inaccuracy of formula B : Assume that the coal has the following analysis : C, 66.50; H, 4. 55; O, 8.40; N, i.oo; water, 10.00; ash and sulphur, 9.55; total, 100. Assume * William Kent in Report of Committee on Boiler-tests, A. S. M. E., 1897. CALCULATION OF WEIGHT OF WASTE GASES. 1 43 also that one tenth of the C is burned to CO, and nine tenths to CO^; that the air supply is 20 per cent in excess of that required for this combustion ; that the air contains one per cent by weight of moisture ; and that the S in the coal may be considered as part of the ash. We then have the follow- ing synthesis of results of the combustion of 100 pounds of coal: CO^ CO HoO O from N = Total Air. O X II. Air. 59.85 lbs. C to CO2 X 2f 159-60 534-31 693.91 219.45 6.65 " C to CO X li 8.87 29.70 38.57 15.52 3,50 " H to H2O X 8 28.00 93.74 121.74 31-50 196.47 657.75 854.22 1.05 " H to H2O 8.40 " H to H2O 9-45 10.00 " Water 10.00 1. 00 " N 1. 00 9.55 " Ash and S 100.00 Excess of air 20 per cent. 39-29 131.55 170. 1025.06 Moisture in air I per cent 10.25 Total wt. of gases, 1125.67 = 39.29 790.30 219.45 15.52 61.20 Total dry gases, 1064.56 O N CO2 CO Total dry gases, by weight, ^ 3.69 74.24 20.61 1.546 Total dry gases, by volume, % 3.508 80.656 14.252 1.584....* Total gases 1125.76 -fash and S 9.55 = 1135.31 total products. Total air 1025.06 -|- moisture in air 10.25 + coal 100 = 1135.31. Dry gas per pound coal 10.6456; per pound carbon = 10.6456 h- 665 = 16.008, Dry air per pound coal 10.2506; per pound carbon = 10.2506 ~ 665 = 15.414. Computation of the weight of dry gas and of air per pound C: Formula A : _.. . ^ 14.252X11 + 3.508X8 + 82.240X7 ^ o Dry gas per pound C = -^—^ , — , —^ — = 16.008 pounds. 3(14.252 + 1.584) Formula B : ,^ ^ 2(14.252 + 3.508) + 1.584 Air per pound C - 5.8 ^ — ^-^+ — '-^ — ^-^ = 13.589 pounds. I4.252 + I.584 O O ^ i' The error in the last result is 15.414 — 13.589 == 1.825 pounds. 144 CALORIFIC POWER OF FUELS, Prof. Jacobus recommends the use of the formula 7N Pounds of air per pound C = .^^ — , ^,^x -^ 0.77 ; ^ ^ 3(CO, + C0) ^^' and in the case given above, where the actual quantity used was 15.414 per cent, his calculated one is 15.434 per cent, — practically the same, and as near as errors of analysis would allow a calculated result. VOLUME OF WASTE GASES. The fan-wheel anemometer is an instrument to measure the force or rapidity of a current of gas. It consists of a fan-wheel rotated by the moving gas, and which transmits such motion to an index showing the number of revolutions. Burnat used this apparatus to measure the quantity of air passing in under the grate of steam-boilers. The coefficient to be used in calculating the flow is differ- ent for each machine, and must be determined by actual experiment. Burnat's formula, V — o. 120 + o. 130;?, means that the velocity is found by multiplying the number of revolutions per second by 0.130 and adding 0.120 to the product. To obtain satisfactory results with the anemometer, it must be placed in the axis of a perfect cylinder at the depth of a metre, as the indications vary with the position in the flue. The formula needs correction for temperature, but the correction of the apparatus much exceeds this. Burnat com- pared his results with those obtained from a formula depend- ing on the depression if under the grate (see page 147), and found differences of not more than 5 per cent. FLE T CHER'S A NEMO ME TER. 145 FLETCHER'S ANEMOMETER. Fletcher's anemometer (Fig. 35) is used in England to ascertain the speed of flow in chimneys and flues. In its simplified form it is quite serviceable. It is based on the movement of a column of ether in a U-tube. The ends of the glass tubes a, b are placed in the flue a little less than one sixth of its diameter. The straight end a should be parallel to the direction of the current, the end b being at right angles to this. Hunter proposed bending both ends in opposite directions, to obviate the error caused if the tubes were not so placed. These tubes communicate with the ether tube cd. The draught across the tubes causes the ether to rise in a b}^ aspiration and to fall in b by pres- sure. The difference of level is read, and then the tubes are turned around 180°, so as to reverse their positions, and the difference of level read again. The sum of the two differ- ences is called the anemometer reading, and by means of tables the velocity of the current is ascertained. The same trouble is common to all anemometer methods. The flue feeding the fire receives only the air passing in 146 CALORIFIC POWER OF FUELS. under the grate. Whatever passes in by the doors or through cracks escapes accounting. On account of this it is certain that the calculations based on anemometer readings are lower than the actual air supply. segur's differential gauge. This gauge (Fig. 34) consists of a U-tubeof i-inch glass, surmounted by two chambers of 2\ inches diameter. Two non-miscible liquids of different colors, usually alcohol and paraffin oil, are put into the two arms, one occupying the portion AB, the other the portion BCD, The movement of the line of demarcation is pro- \ portional to the difference in area of the chambers and the tube adjoining. A movement of 2 inches in the column represents J-inch difference pressure or draft. HIRN S METHOD. The apparatus used by Burnat as a check on his own calculations was devised by Hirn, and is based on the formula of the rate of flow of compressed gases from a reservoir, friction being neglected. The coefficient of reduction used is 0.9, the one given by Dubuisson in his treatise on hydraulics. The main difficulty consists in measuring the difTerence of pressure of the atmosphere in the ash pit and that outside, for the depression in the flues in some cases does not exceed a few millimetres of water. Hirn's apparatus removes this difficulty. Burnat describes it as follows : When making a test the doors of the ash pit are removed and replaced by a piece of sheet iron, A (Fig. 37), which com- pletely shuts out all access of air except through the opening in the middle, to which is fitted the pipe CD^ 13.8 inches HIRM'S METHOD. 147 •diameter and 59 inches long. A tube leads from the front to the apparatus E, devised by Hirn, placed on a table or against the boiler-wall. This apparatus consists of a little -gas holder whose upper surface is just one decimeter (3.9 Fig. 35. inches) on a side. Inside this and above the water level the tube A opens. The bell dips into a vessel of water and is suspended from a balance arm. The balance being in equilibrium when the atmospheric pressure acts on both sides of the bell, if the interior is con- nected with the ash-pit the weight needed to restore equili- brium will give a measure of the difference in pressure. The weight of half a gram {j .J grains) represents one-twentieth millimetre (0.002 inch) of water. The formula adopted by Hirn is yr c- / ^ X 0.76(1 + 0.0037/) F = 5 X O.9A / 2g-^ r> -^' ^Y 0.0013^ in which J7=: volume of air introduced under the grate in cubic metres ; ^ = section in square metre of pipe-opening leading air to the ash-pit ; 0.9 = coefficient of reduction; 147^ CALORIFIC POWER OF FUELS. h = difference of pressure expressed in height of water; B = barometric pressure in the room ; / = temperature of the room ; £■ = acceleration of gravity = 9.8088 metres. KENT'S GAUGE. The accompanying sketch represents a very sensitive and accurate draft-gauge recently constructed by Mr. William Kent. A light cylindrical tin can y^, 5 inches diameter and 6 Fig. 35«. — Kent's Gauge. inches high, is inverted and suspended inside of a can B, 6 inches diameter, 6 inches high, by means of a long helical spring. A ^-inch tube is placed inside of the larger can, with KENT'S GAUGE. I47<^ one end just below the level of the upper edge, while the other end passes through a hole cut in the side of the can, close to the bottom. The can is filled with water to within about half an inch of the top, and the inner can is suspended by the spring so that its lower edge dips into the water. The small tube being open at both ends, the air enclosed in the can A is at atmospheric pressure, and the spring is ex- tended by the weight of the can. The end of the tube which projects from the bottom of the can being now connected by means of a rubber tube with a tube leading into the flue, or other chamber, whose draft or suction is to be measured, air is drawn out of the can A until the pressure of the remain- ing air is the same as that of the flue. The external atmos- phere pressing on the top of the can A causes it to sink deeper in the water, extending the spring until its increased tension just balances the difference of the opposing vertical pressures of the air inside and outside of the can. The product of this difference in pressure, expressed as a decimal fraction of a pound per square inch, multiplied by the internal area of the can in square inches, equals the tension of the spring (above that due to the weight of the can) in pounds or fraction of a pound. The extension of a helical spring being proportional to the force applied, the distance travelled downward by the can A measures the force of suction, that is, the draft. The movement of the can may conveniently be measured by hav- ing a celluloid scale graduated to fiftieths of an inch fastened to the side of the can A^ the can carrying an index. To reduce the readings of the scale to their equivalents in inches of water column, as read on the ordinary U-tube gauge, we have the following formula : Let P ■— force in pounds required to stretch the string i inch; R = elongation of the spring in inches; 147^ CALORIFIC POWER OF FUELS. A = area of the inner can in square inches; d= difference in pressure or force of the draft in pounds per square inch; £) = difference in pressure in inches of water = 2y.yid. AD EP= Ad= = o.osCiAD ; 27.71 ^ ^^ 2y.yi£P E = A o.02>6iAD P The last equation shows that for a constant force of draft the elongation of the spring of the movement of the can may be increased by increasing the area of the can or by decreas- ing the strength of the spring. Applying the above formulae, the movement of the can corresponding to a draft of i inch of water column, the can A having a diameter of 5 inches = 19.63 inches area, and the spring of such a strength that o. i pound elongates it I inch. Here P—q.\\ A — 19.63 ; D — \. 0.0361 X 19-63 . , = 7.0Q mches. 0.1 ' ^ That is, the instrument multiplies the readings of the U tube 7.09 times. The precision of the instrument is, how- ever, far greater than this figure would indicate ; for in the U tube it is exceedingly difficult to read with precision the difference in height of the two menisci, while with this ap- paratus readings in the scale may easily be made to -^-^ inch, \ DA S YME TER. 1 47^ which, with the multiplication of 7, is equivalent to 3^ of an inch of water column. The instrument may also be cali- brated by directly comparing its readings with those of an ordinary U-tube gauge. VOLUME BY AUTOMATIC APPARATUS. DASYMETER. Siegert and Durr "^ devised an apparatus called the Dasymeter, which has been introduced in several large works in Europe, where it gives satisfaction. It consists of a balance enclosed in a cast-iron box with a glass side (Fig. 36). At one end of the beam is a very Fig. 36. — Dasymeter. light glass balloon holding 2 to 3 litres, sealed by fusion. The other end carries a weight balancing the balloon. This weight is formed of a U-tube, //, containing mercury, and is open at one end; the other end is expanded into a bulb con- taining air, which is submitted to the variations of pressure and temperature through the mercury. If the pressure of the air increases or diminishes, the mercury rises or falls, and increases or diminishes the weight on the lever. Suppose an * Oesterreichische Zeitschrift flir B.- und H.-Wesen, xvi. p. 291. 148 CALORIFIC POWER OF FUELS. increase of pressure and a lowering of temperature which would diminish the density of the air one half. A corres- ponding quantity of mercury passes into the arm of the tube, and the original compensating weight is diminished by that amount. A graduated index shows the variations of weight, and hence the variations of density in the gases. An inge- nious arrangement allows regulation by rotating the U-tube on the axis pn. The tube is turned slowly around till adjusted, thus changing the length of the lever-arm. A difference of I per cent of carbonic acid causes a differ- ence in weight of 20 milligrams. One litre of air at 0° and 760 millimetres weighs 1294 milligrams; i litre of carbonic acid weighs 1967 milligrams ; the difference is 673 milligrams. If the gas contains i per cent of CO,, each litre increases 6.73 milligrams in weight; and as the balloon contains 3 litres, it supports an external pressure of more than 3 X 6.73 = 20.19 milligrams (0.3 11 grains). To prevent action of sulphurous acid the bearings are made of sapphire, onyx, bloodstone, etc., and metallic parts of phosphor-bronze. To set up the dasymeter, connect pipe c with the boiler- flue before the damper; the tube pleads to the chimney. By this means a current of gas passes through the box, and shows at any time the percentage of carbonic acid. Siegert gives the following results obtained with it, and the corresponding results by analysis : j Dasymeter, 13.0, 13.0, 12.0, 6.25, 2.2, 16.3, 7.5, 12.5 "I Analysis, 13.0, 12.7, 12.2, 6.00, 2.0, 16.0, 8.0, 13.0 ECONOMETER. H. Arndt has invented what he calls the " Econometer"^ (Fig. 37), which is on a similar principle.* It consists of a tight cast-iron shell, NN, containing a gas-balance. A pipe, * Zeitschrift des Vereines Deutscher Ingenieure, xxxvii. p. 801. ECONOMETER. 149 v\ 0.4 inch in diameter leads to the inside of the flue before the damper; a second pipe, v" , communicates with the interior of the same flue beyond the damper. In the interior, the tube i' is connected to the upright pipe /, which leads the gas to bell e' , and the tube i" to the tubulure g, i' and i" are of rubber. Fig. 37. — EcONOMETER. The balance is very sensitive, the beam carrying at one end the gas-holder e , open below and containing about 30 cubic inches, and at the other end a second holder of similar size and weight as the first. Attached to the bottom of this one is a pan to hold the balancing weights. The tube y conducts the gas to the balloon e' , which, open below, is freely movable in the cylinder g^ by which it pro- duces suction in the tube i" . Carbonic acid being heavier than common air (1.96 to 1.29) as well as the other associated gases, it follows that the density of the gases passing through the tubes depends on the carbonic acid content. The scale is divided so that each division shows one per cent of CO^ in the gases. ISO CALORIFIC POWER OF FUELS. GAS-COMPOSIMETER. The gas-composimeter of Uehling is an apparatus for automatically and continuously determining the quantity of carbonic acid contained in waste gases. It is based on the laws governing the flow of gas through small apertures. Fig. 38. If two such apertures, A and B (Fig. 38), form respectively the inlet and outlet openings of chamber C, and a uniform suction is maintained in the chamber C by the aspirator D, the action will be as follows : Gas will be drawn through the aperture B into the cham- ber C , creating suction in chamber C, which in turn causes gas to flow through the aperture A. The velocity with which the gas enters through A depends on the suction in the chamber C, and the velocity at which it flows out through B depends upon the excess of the suction in chamber C over that existing in chamber C, that is, the effective suction in C . As the suction in C increases, the effective suction must decrease, and hence the velocity of the gas entering at A increases, while the velocity of the gas passing out through B decreases, until the same quantity of gas enters at A as passes TEMPERATURE OF THE WASTE GASES. 15I out at B% As soon as this occurs no further change of suc- tion takes place in the chamber C, providing the gas entering at A and passing out at B be maintained at the same tem- perature. If from the constant stream of gas, while flowing through chamber C, one of its constituents is continuously removed by absorption, a reduction of volume will take place in chamber C and cause an increase in suction, and consequently a de- crease in the effective suction in C . Hence the velocity of the gas through A will increase, and the velocity through B will decrease, until the same quantity of gas enters at A as is absorbed by the reagent, plus that which passes out at aperture B. Thus every change in the volume of the constituents we are absorbing from the gas causes a corresponding change of suction in the chamber C. The apparatus is connected with a regulator, a manom- eter, and automatic recording register. TEMPERATURE OF THE WASTE GASES. As in analyzing coal, cinders, and gases we must have average samples, so in treating of waste gases we need average temperatures. It is not enough to take the temperature occasionally with the thermometer; it varies too much from time to time, even if the readings are taken frequently. We must have some method of obtaining the average temperature of the gas current, and this can be accomplished by means of a heat reservoir introduced into the flue. For this purpose one was devised by Scheurer-Kestner of a type which has been repeatedly copied and modified. It consists of an iron tube, bb (Fig. 39), placed in the flue so that the upper end, covered with an insulating material, is let into the wall to about one half its thickness, the remainder hanging free in the flue^. This tube is filled with paraffin, 152 CALORIFIC POWER OF FUELS. and in this is inserted the thermometer. The large mass of the paraffin is acted on by the mean temperature, but is unin- fluenced by any slight momentary changes which may occur. A self-registering thermometer is very advantageous, but readings at intervals of half an hour are sufficient ordinarily. Of course the opening around the tube should be packed so as to prevent all possible ingress of cold external air. 1 I Fig. 39. — Flue Thermometer. Occasionally mercury is used instead of paraffin. This renders the average of the heat more exactly, perhaps, but has the disadvantage of being much heavier and much more •expensive. There are also many difficulties in handling it which do not obtain with paraffin. The paraffin should be well refined, and have a high melting-point. THE PNEUMATIC PYROMETER. Uehling's pneumatic pyrometer is based on a principle analogous to that of the gas-composimeter, and is now in use in many places, automatically measuring the temperatures of chimneys and furnaces for all temperatures up to 3000° F., and registering the same on cards. The apparatus has been tested at the Stevens Institute of Technology, and the indications pronounced reliable. It cannot be safely used THE PNEUMATIC PYROMETER. 1 53 continuously for temperatures above 2500°, but at that tem- perature and lower it works well and satisfactorily for months without requiring any readjustment. The automatic register is very sensitive, and can be easily adjusted for a new range of temperatures at any time. An explanation of the principle of its working is given in the inventor's own words: ' ' The Pneumatic Pyrometer is based on the laws govern- ing the flow of air through small apertures. ''If two such apertures A and B (Fig. 38) respectively form the inlet and outlet openings of a chamber C, and a uni- form suction is created in the chamber C by the aspirator D^ the action will be as follows : "Air will be drawn through the aperture B into the chamber C\ creating suction in chamber C^ which in turn causes air from the atmosphere to flow in through the aper- ture A. The velocity with which the air enters through A depends on the suction in the chamber C, and the velocity at which it flows out through B depends upon the excess of suction in C over that existing in the chamber C, that is, the effective suction in C . As the suction in C increases, the effective suction must decrease, and hence the velocity at which air flows in through the aperture A increases, and the velocity at which air flows out through the aperture B de- creases, until the same quantity of air enters at A as passes out at B. As soon as this occurs no further change of suc- tion can take place in the chamber C. "Air is very materially expanded by heat. Therefore the higher the temperature of the air the greater the volume, and the smaller will be the quantity of air drawn through a given aperture by the same suction. Now if the air as it passes through the aperture A is heated, but again cooled to a lower fixed temperature before it passes through the aper- ture B, less air will enter through the aperture A than is ^ \c (N Ov °_ 4) u CO VC oc lo °5 3 •jiv O 'I- O- 00 T >n d'Z oc vo ll en 3 s. g, s 8 ^ ■^ s a o VC VC ov r^ o C7V ^a c •s:iDnpoj(i oc oc U bo C ►" •4- cn ""o >> — o X •§a o c " J, c O ^o •O •sjonpojj Is C ^ c CI °A 8^" li O o •uaSAxo o'C > ^ c C o o O o C ■I- X U •3iqnsnquio3 g U U U E + + ►> 1- ' (N u u . -*• t^ •<*■ Tj- N fi O 0^ O CO 00 o o •SJDTipOJd; ^ 1/1 t^ -^ t-> ro CJv "^ N vo r^ J^ 00 o m a < rt >. -<1- -<1- -4- N m u . c n o o S; 00 °o Ov o bjCU o •JIV .-= "^ S t "r T ov ^3 ~ w J 1 "• N -^ C^ ■.j- VJ 3 3 i2 «j-2 a o vo !^ t^ o 8 "n &a O c 4J •sjonpojd _ vo r ? ^ ° q "^ >^ X O 03 5 ^' n M ► I Ov lO -^ •uaSAxQ . t^ m w o >o (^ t^ o ^ vo ro lO o § 00 5 t 1 00 "^ m -1- 00 ■* 00 ^VO 00 vo -* c >! ■* 1-1 ^ ro 00 fl 1 1 1 II II 11 II II <5 •S5onpojj o 8 o 9, oo c9, u ^ ' u X ^^ ^^ 00 N ^ o\ 3 •naSiixo N VC ft r- VC vo 1! II 5:i O O "o 00 N s •3iqilsnquio3 ^ - vo 00 Cfl ; « ; •i ffi !q s CT u u a 3 J* iT « A c c ijfl c f? s c c o s « o X X "O .a >, U ct 1- c >. « ^ L C- C- K S w 202 TABLE VI. T3 1 ., XT) tn Tt M M M »-~ n n ^ Tfo w vo o^ en c § •jonpoja -° Ji <> ri- r^ <> f^ r^ u 0- tl (jt, COOO C<-5 M en a- CO u < ^ M iri w t-( S. IT) w -i- -1- O en o if •Jiv w *:; ^ r^ r^ M in ^ 9J ... -t roii " (jP- en vo CO en '-' oo D 3 "-^ M rt O"- . U u ° ffi •usSXxo X3 *j QO o en "^ CO en c ^ C4 >-H CO n- od ^ 6 en O c^ fr\ (J^ t l-l ~ON U^ 3 •saiqtisnq .::f *j cs o- r^ o -^ r^ > > -mo 3 snoasEQ -
  • - S « 3 •uaSXxQ "3 N M W M '^t en 'Z P O U > < •giqiisnqmoj 5 uugx t 3: CJ Q . ^ r-. rf -r N en ^ — V) O Oco CO O^ O j3 U-) t^ Tt rx en o -^^-S Vh ^• •siDnpojj '"^ ci O en >i-; od vn ^ w en M M g ^ -t- r^ -t- -t 04 en W -u 3 « «°5 c o -^ •jjv I/,' o oco CO o O O JJ *~ j3 ir> i^ -^ r^ en O^ > CLi-- 'ZI '-' M U-) d Tt r^ •I- X O 3 M cn M I-" t^ en w O O oo ^§ a o c •siDnpojj (^ o en r- o O j3 o en lo o O M t b .^c3 u ■-^ en oi M d^ vn ^ o >^ w X o r^ en HH o O CO •uaSAxQ (/)• vo en r^ O O 01 :^ >> jD O en IT) O O ^ cc •-* cj M o CO •^ en f CO rtcc ■^o oo o c •<^ c^ -^ M rf cnoo en > •sjDnpoJd Q o o o 2 o - 01 01 'Z rt en uuun:uD: < oo Ol 11 1^" •uaSAxQ e^ vo o o II en M W M II II O O CO o 01 W M 1 •3iq iisnqui03 C4 (N CO (N >0 M M C^ M CO 01 > Jc 1 i •d : nJ -1 ■J; 1 • J 3J (U oT < 1 i G C o ^ C c3 03 g3 >^ .1^ C UUK 2 W TABLE VII. 203 w s D J > Q ^ < H K X! W coo CO • • • a> c^ vo rt- CO . • • aj"-'^ C> c< U-) u-> r- • • • rv 3 ^ t-i M m" Tt * • . r-s C> ^ f^ • • • CO 00 O^-rt ' ' • «j 3 to in U-) CO CO • • • Ph w M M 0" r^ ' * 01 u-> (M (N C^ C^ M °a CV 3 O 4, 3 Ph O Oh 'US fC) U-) M M O O vO CO O CJO C) C \0 u-1 O^ C^ M CO W CO CO Ti- 10 CO r^ M o r^ • O^ M M CO CO • o f^ Tt coo • t^coTj-ci p o u Ph hU kC Ph Dh O "o 'o 'o 'o 'o 'o > > > > > >^ Tt w c^ CO M M C::, UUUUUU D:En:En: ^E^O u uu uuuu • -a • a o TO ,-s ^ . ^ c c>> -::: c OJ o . . >. 03 N ^ ^ ^ *-" frt *'-' >;-/^ o t: t: 5 rt rt rt p:2<:w wpQuuu 204 TABLE VIII, = 5-5 ii 6 6 ■^ o o XT) o l-< •^ CO m c<^ ■^ to ai> o ^1^ O \o _22 o t^ bco- 6 . rn»oO »-i MulOO O •^ OOioO vnu-)i-tco coo O rrwN 0^ o in CO u^ oo 1^ -1- CO O CO O O 0^ o M o o o ON CO O D S5: u II II II X X ^ d o. C < z u u o U3 o 1^ 2 »-, 73 >» a. ^ E O c/5 TABLES IX, X, XI. 205 TABLE IX.— TABLE OF SPECIFIC HEAT OF GASEOUS PROD- UCTS OF COMBUSTION REFERRED TO THE PROPORTION OF CARBONIC ACID. Proportion of Specific Proportion of Specific Carbonic Acid. Heat. Carbonic Acid. Heat. 5 per cent 0.312 II per cent 0.319 6 '^ *' .... 0.314 12 < ( ** 0.320 7 '' " .... 0.315 13 < i '' 0.321 8 '* '* .... 0.316 14 ( I '' .... 0.322 9 *' '' .... 0.317 15 ( ( '' .... 0.323 10 ** '' 0.318 LE X.— HEAT OF VAPORIZATION OF WATER AT 0' 230° C Temperature. Heat of Centigrade. Fahrenheit. Vaporization. 32 606.5 100 212 537.0 230 456 676,6 Latent heat of vaporization, 966 (Regnault). TABLE XL— SPECIFIC HEAT OF WATER (REGNAULT). Temperature. Specific Heat. 0° 1. 0000 10 1.0005 20 1. 0012 30 1.0020 40 1.0030 50 1.0042 60 1.0056 70. 1.0072 80. 1.0098 90 1. 01 09 100 I. 0130 Temperature. Specific Heat. 110° I-OI53 120 1. 0177 130 1.0204 140 1.0232 150 1.0262 160 1.0294 170 1.0328 180 1.0364 190 1. 0401 200 1.0440 io6 TABLES XII, XIIi: TABLE XII. -VOLUME OF OXYGEN TO FORM WATER WITH THE HYDROGEN OF COAL. Per Cent of Hydrogen. Oxygen in Litres per Kilogram of Coal. I 55-9 2 112 3 i68 4 223 5 279 6... 335 7 391 8 446 9. 502 Oxygen in Cubic Feet per Pound of Coal. .896 1.792 2.699 3.585 4.481 5-397 6.283 7.170 8.096 TABLE XIII.— QUANTITY OF AIR REQUIRED FOR PERFECT COMBUSTION OF FUELS. Fuel. Composition. Air per— Carbon. Hydrogen. Oxygen. Nitrogen. Kilogram. Pound. Coke 98.0 95.4 87.0 85.0 84.0 77.0 90.0 71.0 58.0 50.0 85.0 68.7 58.0 34.0 1 .0 0.5 2.2 5.0 50 6.0 50 2.0 5.0 6.0 6.0 14.0 22.5 23.7 5-9 5.0 . cu. metres 10.09 9.01 8.93 8.68 8.79 7.67 8.53 7.02 5-75 4.57 10.76 14.20 14.51 3.16 .72 cu. feet 162 06 Coal, anthracite bituminous . . coking cannel 1.8 4.0 6.0 8.0 15.0 0.5 144.60 143.40 139.41 141.07 123.15 133.90 112.43 92.36 73.36 172.86 227.93- 233.06 50.70 11.56 smithy 19.0 30.0 42.0 I.O I.O 1.4 43.0 21.0 Peat dry. ... Wood, dry Petroleum Natural gas Coal gas I.O { ' . ■ 6.2 3.8 3.4 69.0 Water gas Producer gas TABLES XIV, XV. 20/ TABLE XIV.— RELATION BY WEIGHT AND VOLUME OF THE COMPONENTS OF AIR. Air contains by volume : Nitrogen 78.35 Oxygen 20.77 Aqueous vapor o. 84 Carbonic acid 0.04 100.00 Deducting the carbonic acid and aqueous vapor, we have : Nitrogen.. . .By volume: 79.04 By weight : 76.83 Oxygen '' '* 20.96 '' '' 23.17 100.00 100.00 Ratio of nitrogen to oxygen : By volume, — = 3-77I- By weight, — = 3.32. Ratio of air to oxygen : A I Y A \ t- By volume, — = 4-77I- By weight, — == 4-3I5- Ratio of air to nitrogen : Air A.ir By volume, — — = 1.265. By weight, -— = 1.302. TABLE XV.— IGNITION POINT OF GASES (Mayer and Miinch).* Marsh gas, CH, 667"" C. Ethane, C^H^ 616 Propane, C3H 547 Acetylene, C.H, 580 Propylene, C^H^ 504 * Berichte der deutschen Chemische Gesellschaft xxvi, 2421. 208 TABLE XVI. TABLE XVI.— SPECIFIC HEAT OF WATER. Degrees Rowland Bartoli Centi- Regnault.i Rowland. 2 (corrected) and Ludin.5 Griffiths.* grade. Pernet.3 Stracciati.'i O 1. 00000 1.0080 1.0075 I 1.00004 1.0072 1.0068 2 1.00008 1.0065 1. 0061 3 1. 00013 1.0059 1.0054 4 1. 00017 1.0052 1.0048 5 1.00022 1.0056 1.0054 1.0046 1 . 0042 6 1.00027 1.0049 1.0047 1.0040 1.0036 7 1.00032 1.0044 1.0040 1.0034 1. 0031 8 1.00038 1.0037 1.0033 1.0028 1.0026 9 1.00043 1.0033 1.0026 1.0023 1. 0021 TO 1.00049 1.0026 1.0019 1. 0018 I. 0017 1.002070 II 1.00055 I. 0021 1. 0014 i.oof3 1. 0013 1. 001636 12 I. 0006 I 1. 0016 1. 0012 1.0009 1.0009 I. 001242 13 1.00067 1. 0012 1.0009 1.0005 1.0006 1.000828 T4 1.00074 1.0007 1.0005 1.0002 1.0003 1. 000414 15 1.00080 1. 0000 1. 0000 I. 0000 1. 0000 1. 000000 i6 1.00087 0.9995 0.9995 0.9998 0.9998 0.999716 17 1.00094 0.9991 0.9993 0.9997 0.9996 0.999432 i8 I.OOIOI 0.9986 0.9988 0.9996 0.9994 0.999248 ^9 I. 00109 0.9981 0.9984 0.9995 0.9992 0.998864 20 I.OOI16 0.9977 0.9979 0.9994 0.9991 0.998880 21 1. 00123 0.9972 0.9977 0.9993 0.9991 22 1. 00132 0.9970 09974 0.9993 0.9990 23 I. 00140 0.9967 0.9974 0.9994 0.9990 24 1. 00148 0.9965 0.9972 0.9995 0.9989 25 I. 00156 0.9963 0.9972 0.9997 0.9989 26 1. 00165 0.9960 0.9969 0.9998 0.9989 27 1. 00174 0.9958 0.9967 1. 0000 0.9989 28 1. 00183 0.9958 0.9967 1.0002 0.9990 29 1. 00192 0.9956 0.9967 1.0005 0.9990 30 1. 00201 0.9958 O.99D9 1.0008 0.9990 31 1. 00210 0.9958 0.9972 I.OOII 0.9991 32 1.00220 0.9958 0.9974 1. 0014 0.9992 33 1.00230 0.9960 0.9977 1. 0017 0.9993 34 1.00240 0.9960 0.9979 0.9995 35 1.00250 0.9963 0.9981 0.9997 36 1. 0026 1 0.9963 0.9981 0.9999 ^ C = I + 0.00004^ -f- 0.000009Z''. 2 American Journal of Science and Arts, 1879. 3 Ueber die Aenderung der specifischen Warme des Wassers mit Aenderung der Tempera- tur. Vierteljahrsschrift der Naturforschergesellschaft in Zlirich, Jahrg. XLI (1896). * Sulla Variabilita del Calore Specific© dell' Acqua. Estratto dal Nuovo Cimento, Set. 3 Vol. XXII. 5 Inaugural-Dissertation, Zurich, 1895. * Philosophical Magazine, Nov. 1895. FUEL TABLES. These tables contain all the available information covering the data required which have been published to date. They contain analyses of the fuels, and the heat units as determined by the authors, whose names are given. In some cases it has been necessary to recalculate the results as published by the experimenters to conform with the standard adopted. This applies especially to the coals and solid fuels, the data for which are given based on pure dry coal, i.e., on the combus- tible present. If the actual test of the sample as given is desired, it will be easy to make the necessary deductions. Some of the cokes and some of the natural gases have been calculated, the calculated results being within the limits of experimental error in these cases. 209 2IO FUEL TABLES. o « '^1 CI o •qsv •J3;^AV •jnqdins •uaSojji^ •uaSAxQ •uaSojpiiH O r^M inino COM Tt oo tn fOvO w Tf rf \o N N oo Tj- O un Tj- (N ino rOvOOooooOtotnoo co r>.x^coi^cooor^r^t^r^ r^ O O lo 1"^ CO 1^ M O vntoo vnOoooooo O O CO TfvO M M r^ M o O O O N -^ u-> c^ c>co oo O to f^\OVO»r)U^TtM O U^ C^ Oco 0>co O^ un O •^ •^ '^ Tj- lO IT) xr^ IT) »n rl- T^ T^ o Oco en o wo M O O coco en en en o en M ii "■X? 4J s ^ y PQ E §1 ►J - " i:=.ii ;2 o t-J ^ M c/:5 !> r^ w oo -too en Tt en -t en o oo \0 r^o ■* Tt en rj- en l-H 1-1 '-''-', c^ VO 1^ I-- r^ en rf r^ O^ r^ M vn >- in oo CO r^oo r^ O O Tt- N -^ O M M M CO x^ O i^ o x^ c^ c^ t c> GO o c^ oco o O M O M oo CO o r^O M vn eno en en w en »-< en U-) 11 00 r- o rt (S en O oo Oco o o oo u-> -f -f O HH -to O o C^ O en O M MM r-^ O Tt en o C) oo r^ Tj- oo u-)0 O r% r^ r^ r^ •u r3 =5 ^ COAL. 2IT h4 < O u o < Carpenter Carpenter McConney Forsyth McConney Forsyth McConney Forsyth McConney Forsyth McConney Forsyth Carpenter 4) O O O O >^ u-> O r^oo CO r^ o m ^ CO vo to '^ in OO r^O i^Ooo civo c») coc^ ino oo o O Ooo C4 ■-• looo rl-'Tl-t^ooO -^Om t^c^ o ClOO -^O M 0"-)M COCO-<^COOt^OM ^ coc^ cococococococo'+cococow cocoes u OO O O CO OO M O vo O CO r^ M 00 r^oo i^ t-»oo coOiDco Or^r^M M oo N vnO incoi-i CO utO (N oo C^ O COC^■N^^-lX^ r^vO O^ c>< COM Ttc^ coc^ r^co-fO^T'^r^O r^M O •qsv '^ O up M M ON 6^ \r,c6 M rt r^ \n COM tnco O ■^Mco c^i^Or^Ooo Ooooo N OO ^O u->oo co u->6 rA':3-ci dod d 6o d c>r>«d u-)o cj l-HMl-ll-IC^I-l MM MM dCOMM •J 3JBAY tJ-m hi '^xDcoi-i MCOO Tfcao a^ CO rt lAo rj- d coco cO'^'^u-ic^O w M CO •jnqdins •uaSojji^ •uaSiixQ •inqdins 'uaSAxQ •uaSojpAH rt o O xn Ov ON M O d >n M oo in C^ H O^ (^ O^co oo ON a> z^ HH C^ VO r^co oo o > O O t^O O^oo CO 'i- CO CO CO CO 0) xn M O M M CO tJ- -^ Tt- •" 2 ^ o u O ;:i -M w ^ ^ S-H 8 .S Oh 212 FUEL TABLES, J5 (U (U ^U- iflU---- '^^ (U (U (U ^" ^r ^ c c c "i* 5i ^u ^u ^u e^^B^^ - O rt 00000-1-000 OOOOOf^voOO — r-» O c^ M CO -t t«^ r^ si OO -tcoc^co --i-O^r^M cncn-^oo Oc^O r^oo CT^CO "-I O wr^co cnvo tn co m r^ r-^o -i- w o fn ■^cnc^ci c«-icncotncnc<^c*^c<-)cnc<^mcnc*^t<-5'1-1-rf-t CO O'^c^ »H oooo r^oo c^ r^i^N tj-O moo Oco O ■^rONO cooo vO O <~^0 »r>i-H ino cni-i O ir>Oc.t^r>.t^f^r>.r^r^co r^-r^r^r^r^f^t^i^ ■qsv \r, tnoo N O "^ M in T^O cnoo N a^ O en •^ O^ 6co<>c>wo •JSJB^V CO CO od r^oo r~> r^o r^ en c> •^O n r^ •jnqdins •u3J§oj;ix •uaSXxQ •jnqdins 'uaJSAxQ •uaSojpXH t^ m '^ O I-" 'i-oo en o ^ M N «o T^vO Omt^iou^'^O^OC) Nin^tN O^O O NxoN •^co M o^t^^^ 3.H ^ c C3 • -O^ „ bio c c 't. >¥ COAL. 215 c o o o vn M o HI O 00 mi-tNO^MMNi^'Tf u->oo Tfoo in co c<^ m xDOoo Tj-oi-^-^H-i ir>0 i-i i^u-^O O cnr^W OmcnM O i^ r-» »ri ■^00 00 c^ O 'i- c^ 00 O Tl" O C^ O '^ c<^\0 in M U-) c>o •qsv d c>o 00 c<^0 inioci O O N •^00 or^M T}-a^cnOOoo CO N 06 M o ^ \}\ ^o M T^ d^o IT) en tJ- r^o c^ •J31BA\. r^ M C>vO en W O cno r^ O O en ^too tnc^oovO m cno^^cn tAo vAm xnd^d^M fi d^od d^od ■^i--«d t-^ d^cncJ «nd^r-~-d •anqdins Omint-i tn'^^o OcnMco ■^oo cnr^ OMcnodcn'^iHd^O'^-NMNdMMd •usSoJii^ •uaSXxQ •jnqdins •aaSoipi^H 00 O -"^C^a^cno -"^c^oo T^o^T^M (n "^mcn-^O OC> Of^r^oo NO vnocnoo on m 'tt^oo o^oo moo o O . 1) lU OJ ^ W3 OJ 3 P I . I ^ C h d N J? '^ fl) r! V Jr ^ 214 FUEL TABLES. •JajBAv •jnqdins •uaSoJiijf^ uaSAxQ ■jnqd;ns •uaSoap^H 5_) TO o o o S-T^ 3 b/3 bJD 3 IT) h- r^ en c<^ (X) in w r^oo CO CJ O^ O N c<^ -t- en en ■* CO o^o vO t^vo en o^ o ooooOior^wiDp-i o or^cnMcntHr-fcn u-) en M r^ u-> 1-1 vO O vn cs O r-. O^ rt en Tt en O Tf i^ c^ en m r^ M M eno en O r^ o t^ r^ o oo i^ r^ r^ t^ t^ O O MOO r>.enir)"^- M 1-1 enmco t^r^co vo r^- o r^vo vO O o O O"' *+ C-1 O^co O m CO >o es r^ t-^ r--oo r^ M O moo O r- IT) M en O O ■^ O O M \0 u^ O^ Oi -j CO en en in M vo r^ i^ O L^ O m O I- en in in lo IT) lo NMOMOM'^in T «^g' OO r^ M CO in en M r^ C>co r^ o^ enNenc^M(NMC< U 3 c3 a; o u 1^ . -;:! rt \^^% '^ i1 ^=y u a, ^ i3 ::: 'H C/) < m ^ < - 1 W O m r^ r^ en o CO O O (N en (N C) C> en en en in O en N in ■^ m Oh • s • 3 • ^ . o • b/)^ : c c • g > A>\ COAL, 215 >% ;^ D 3 < "0 ^ 88 XT, Tt c *;; ra M M ^ -D tn si 15 to 00 00 U •qsv r^ t-N U31BAV •J iqdins •U9 Soj;!|S[ •agSAxQ . inq dins 'u aSc 'u •uaS DjpAH rt h c vO 10 ^ r^ u~, > (T) CO •a Tf 0^ • £ ^ IT) c c t c ■P| d^ £^ :^ C . M 00 r-s in -rf ^0 ino vO en en rf en i-- M M 00 r^o in r^ en r^ m c> 00 IN c> en e^l inoo t^co x-^o 0000 '^ ino Ooo in M ^ en r^ t^ en in M l-H M M ^ en en en --t- o> in r-^ N in ^ 00 en ^ Tt- Tt Oh CI, — c7) On m 00 (/) 00 ^ en en 00 en M M vo r^ -^ in t-^ M en 00 00 en W QO 00 M in 04 C^ ^ C^ en w M rt o^ -too t~^ o> en en en M Q^ M co coOO r^cnwu-)ir>OOr^C< inri-oo inoo - locoo \r, O -^(N Om moo Tl-Q^M OVilOOOCO O^Ot^OooOOOr^ M M M CO N u^ c< \r\ o ■^OO vO t^ "^ "^ c^ 6 M vo o vd O COM M ■ri-Moo win Ovd-> vO O Tl- rt rj- Tf r:f Tj- RR?^^ S S M CO M N CO ■* rx i^ i^ r>. r^ r>. O^CO to CO O lO rj-co Tt r^ O '^ M o q CO M M coc<^cocococococococo M o o o o c< c^ CO r^o o CO f^ M TtO O tr)0 CO r^ CO CO CO CO CO CO CO M COO cococo O TfioOmi^r^ococo co aNOci'-^dod^cocfr^^dNdNdc^ ;3 b/j c o o a- o -^ >^^' CO A. 217 G »r> Tt- OMO r^ i-c M r^ w vn '^ ^ Tl- Tj- CO xo ^ g CO r^ cno Ou^toO OC^r-o u-> rococo r^t^r^oo r^i^t^r^r^t^r^ ■^ CO C>\0 CO N CO coco CO Tfoo M 00 CO 00 vO -to 00 r^ r^ r>- 1^ 00 00 •qsy M CSl « CO M C^ TtM0"^OOO0mvi-)00 r^co CO M •^ CO r^ a^ CO r^ c^ 00 ma^OOOWi-iMf-. O o q M T}- N CO o^ o^ r^o (N 00 O ^ M vO Tl- rj-o O vo o IT) c^ o t~~> r-«\c o ^ C/2 ^ ^ § ^>^ 13 -^ *f o Q ^ ^ 13 JJg ^ :: > - ^ c3 j^ - O t3_g ^ ^ ^ >y3 oj o ^^^ - im § g ^ ■ •■ • I cS o ,0 > ^1 o 2l8 FUEL TABLES. C rt C G si O O C C ctf E <" o ^ si OwOOOOr^TfOOc<-)OoDOOr^ooooOOOO^O-'OC-iOOO^OooOOaoi-HQOvOcomOc^■^-^rfTt rj-O -T Tt- -1- l-O un 't 'f -f Tf en u-)vO inOMCoO'^O"^ •^vO N CI r^ r-^ xnvo r-^ c<^co •^ r-^co o in rt m to mNMO^Ortc<^cnc-(Ciot-ic^ coco oc^^c^nmnhhcoo^ oo oo oo r^co oooooocooocoooooco ooo oo oo r^oo oo oo co co oo r^oo oo cocooo l^T^fmO C>ooco moo tTvOoo OvO Oior^oco •^O »nN tJ- •aaiT^A^ •jnqdins uaSoji;^ •uaSXxQ jnqdjng 'uaSAxQ r>. r^ t^ r^ t^ O O vO t^ t^ uaSojpXH U-) in in ■^ in O^ O '^t in ^ rr vn in - - _ -rj ^ 2 =" o o :z;;zi H > C '^ - - ::;:!=-:: C (u en tt H en o< c< 000 CO 0^ P-H M vO Tf M O en rto-^O 00 O S'OOoo r^ KoOO O O en Tf C^ O "^ o «^cni:^OjJ>'^u- ir>invO uicn'^l-O r S^^ enenoo ■ ^co 0< O O T M t^ 00 I «^TtM c>0 looO en oooc^OMu-)OJ> 00 "^ ^^ ^ r^ r^ inior^r^inu-iooco r^r^C7>ioS; ooco r^ 6 _• h ■^ 03 > OJ S .1:^ C o -^ "" :^ uuuuw w w Onra . C< ;^s ^ p: 220 FUEL TABLES. O (U 'C to (u o 3 •qsv uaiB^ •anqding ■uaSojii^ uaSAxQ •jnqd[ns 'uaSAxQ 'u9SoapAH ccoOQO OOu-1, t-.tnc^p-H c<^0 cnoo c^ a a o r^ r-^ r-»vo O en -f- r^ U-) inoo I 00 N O c<-) M o CO CO oo CO CO r^^" cjo co co c« co lOvO T^vO O Tf i^ vO o r^o o o o o CO r^co CO fl C C/3 H vn-tu-iM w Oco a^c<~)M m O 01 O u-> -foo O^ 1-1 O O N •^ 1-1 O CO cno O O O "^oo t^ r^ r^ r^ r~^ u-1 O C4 O O vo r-> (N CO aNvna\i-i tn'tvoo '^f coco t^O) (N O »r)inir)\ri cnoo r^ M -to p^ CO IT) O u-)iriu-)u^co ^'coo O Ococo OPIO r^ cAu-lCO-fd M M M c^iAco od oo CO r^oo CO CO CO CO CO oo CO ir)co u-)r^ir>\nu->inO co COU-)COOOPlQOvOu-)MTl- ■^- CO c> ID 6 oo -i- r^ pj vn cococococococococococo \n XT, XT, \r, CO o O O O uiO r-- r^ (N r^ 0"0 o co r^ m co CO M Tt-OO M ci irir^rfcOCO rJ-u-^'TcOu-irrT^Tj-'^u^-^ Coj^SoS:. 3csrt <;pq WW W fflUU CO OO C/2 O o COAL. 221 o U ca-::::::::^::::::::::::::::^::-::^::::---- c o • . in O O c^ oo vnoo Tf-OOcoOOcnM t^oo r^oo ■^- O O t^oo O w O HH c^ (N o irio r^c<~)0 lOM t<^M Ocoooo c^o mo O cnM \r^\o O ■^ c^ r-^ (T^oo "^i- CO M cq en coo McouiMOc^Nio^fM T^co o O i-H t-H r-.u-irot^coO inr^oc C^O •^^riino inr^vnior^co m O CO o^oo •^ O^ M o ■^ ir^ Oco O^co oo M o ^ CO 'i-oo ui m ooo loo qsv O M lOr^T+rj-t^TtOO O CO'^CO'^Tj-^NO -^OO COi-c c^ •J31B;VV cotj-com '^r^cO'^iocO'^m ■^r^t^r^tno u->tj- •anqd[ns M M O O O (NM O'^OOOOOOOOOOOOOOO •aaSojji^ 'usSAxQ •jnqd[ns •uaSojpi^H T^\ncoiou-)0 coo u-)u->co xncOinOco O O O Ooooo uiOcoO (V, O r^O M O O -^ CO M r-^o oo ■^m Tj-OH-vr)u->uni-iO O»j^co ^n^^O r^d c) r-^r^o" ococJ d m rfu-id cood r^'^o^ci m c^ n O O cO"^i^Oco N unir)cou->co O O N vnQ O irioooo inO coi-i \oCT>0 coc>^ O Mvno O M MOcoo Or^t-i com 0"^O^"^t^u-> rt r^ CO CO tJ-c» CO CO \ri\d d r^ lA loo r^ ^ to -^ coo too >+ lA m cocococococococococo'^cococococococococococococococo vn^DlnOOOl/^OOOvnO"^u^OOu-)OOu^OOOOlOvo r^r^t^COO O t^O^COu^O nI-i-hOO -^m O C^ C^ \J~>yO t-^vncooo •^lAr^'^od '^'^covnM cou-)u-)ir>r^ooo cotJ-'^oo iri \n^ \0 O H-^ o U ^ G D O c .S - rt o ^< o "^ a G o p^ .i: iu £.==.= a. „ o 222 FUEL TABLES, (=1 rt > *; c 1 5 - 3 < VH "6 vO O en C> i23 h 8:? c'^ CQ • w 2-2 u o ffiU 1 oo U-) O CJ r^ O •qsv trioo •j3aHA\ O c^ •jnq djns M U-> 6 6 •uaS OJ^'N •U3i gXxo •U3x ?o JP^H ct! O d H id O Tf o QO >ri ^ c3 vO Tf > N --^ . cnO y O rl- •S b vn Tf c cJ ? rt :: r >. ^ L^ :: Songwe R m z c P! c (S •— > 3 M in CO O r"! i-i ino O 't-O CXD 5 vO i-i O I-I VO M '-' M o ^ in O ^ O ■^CO 00 CO ■^ CO in in OvO ino c^ r^ u->co O r>. Tj- 1^ N in CO r-^ CO '-' a^oo M o o •^ r~» N ^ \Ci •"I c^ o O o c< N „ o '^r o o ^ QO CO M 1 t^ o M o o ►J < U-) o in o CO o O to H ■^ -i- in N (/J c^ C^ w D < CO I-I '^OO -r '^ O '^ ^ o CO in in o o 4? O - - c> -^ i! ^ - ^: -l I-I d w '■' O C> O QO O c^ to O O^oo CO '^ rl- M vO vO r^o cooo ccMOOi^mrj-o^ ■^ Tf t3- 'la- m Tt co-TTrTTj-cocO'^'* r^ in O f^ PJ r^ O '^ cooo rj- -1- N 11 in in M in 00 o^i o^i-( cococo w W to W C< N o6 &■<) 6 CO r- c^ o 00 OO oo OO r-.co t^i — r^o ininino in N -^ n I^ vO o o -^ CO CO CO CO O O oo O r^ O r^ ^ Tl- rt in , . w . * 3 »« ^ ro : ,2.2 ; < ; S !^ . 3 ', -J^ . bfl . << : I-S.S : ^ • O < mg Albrecht lerer-Larisch , Austria . . . s : rchen, Hung s, Hungary Hungary (av o, Istria - : - 1 Erzher Karwii Rossitz Pilsen Wiloze Funfki Szabolc Vasos, Carpan 0^ 2 = i COAL. 22J . flj 1 r -U I O ; ►i^ „- O ^*^ -^ ^ 'S :2 ^£^30. T3 -^ t o O u t-a 6 loOOO'tOOO en r^o CO u^ a in vn r- CO — ir> -i- W ■0 00 C>00 ^ ^ 'rf CO CO CO ■qsv •J35BAV •jntjdins •uaSoj^ix M -^ M a M S ^^2^;^ ^ 00 CM^ CO N ^ "N in <* in 00 M CO M xn MM n- c^ •uaS.ixQ •jnqdins 'uaJSAxQ •aa^ojpi^H "5 > c^coO r^r^Oiococ^ M C^M C0ir)'<^0 000 M inri-"^r^vO inr^in M Tj- r^o -^oo t^vo r^TfM cooo Noco Tj-co COCOCO N^COCOCOm l_,Mt^l-lO»-'>0>-l 01 cocon-Tj-r^coco r^invo M 00 coo O'^ 01 rx r^ CO "^ -rfco 00 in Tt C> r^o C^O CO CO r^ t~^ in r^ CO w coo ■<* Tt CO coco Tj- CO in in ino -^ooo N a^coM CO vO COCO'^l-M COCOCO c3 :: ro-" O -. - O 7^ |q s§1 •n 5 'C i^ « -K S ?^ :2 .^ ^ I =2 g :^ -^ g ^ I - o a ^ - - - - Tf rj- (S (X) CO in in in 01 OS CO t^ CO -Tj- •^ CO w in cnco CO CO 01 CO 01 01 Ti- Tj- OMMOoiinoicoi-ir^ 01 O'^0coi^oioor~<>-i inooo cornoi Q O^O^O '^'^r»0 ■rfco O^ \rt O^ O^ Mvo t^'1-r^oo ■Tj-inr> OOOOOJOOOOO in in CO Tf 01 8 8 8 8 in CO M ^^ 2:2. CO •^ o^ 01 CO '^ in r^ Tf M t CO ^ Tt in rt-co w r^ rj- in ■^ CO !>• m M 01 M M 01 c>o in in t^ rt -* 'st- ^ o c/:U fcJO C3 3 3 -^ r ^ „' < ^ > g ^ Ph 224 FUEL TABLES. 1^' WcAJ o w II O O O O M o O oo O i-i CO O to tJ- U-) M IT) N IT) inO iri ino OmO'tOOO'-I- CO O-^w cnc<-)N M CO O O O rfoo N Tj- M Tj- o cn O M O u-)oo vO "^ "=t O U-) vn in m in u-j lo o o o o o o O O O "-> "^ o in vo c^ ■^ O O CO CO Oco CO O^ OtOOOOOO WO O cninO inm oocoo ^inin^'^l- cococooooocoooco O O O O O O O O in O a c<-)0 ^ coo CO r^vo in en CO oo CO CO CO CO oo ■qsv •J3JBM •u3Soj;i|sj ^. CJ O r- M rt Oin O -1- en 00 o O CO oo r^ O O O Oco r^vO O o o ^ O O O O O O O O O O O O O •jnqdps 'uaSAxQ vO CO cno :?o 1^ in CO M CO -^ in O CO in f-> r^ vn M O r^ -t a in Ttoo r^co O i-i r^co \0 w u O en t-1 M "t M en M M oo o in in a M CO •uaSXxQ Di •uaSoipi^H O O (N r^ ■^ tJ-OO O 00 m O O m r^ O en M in en r^ enoo m r~» en O " w O rl- r^ ^ ^ ■^ en Tt ■ri- ■^ o Tt en envo -^ O en '^ en ■^ in en "rt rt N in o in O O M CO O o CO Tt i-« O O Tf M M r^ in O O in r>. in in O N oo i^ c^ r^ in c e2 oo OCO CO Oco o M -1- O en r-- en OCO oco CO o 1-0 O H- c< M r-. CO oo o Ooo oo CO > O O en CO o O M r^ in o o O en r^ inoo w r^ m O in i-H o O O a! ^vO r^ M en i^ (N en O eni^ in o "^ en cno m i oo N (N M 'i- c^ c^ i-t M en "^ O r^ M o o 'i-oo en w eno m r-- ^^t fc 00 oo r^co O oo oo CO CO 00 CO oo O CO CO inO vO r-^ r^ t^ r^ r^oo 1-1 h-l CO C/2 o - 2.1 • C • pi - - - >^ b^ muuQ COAL. 225 CO 1 2- ^ C3 I s S n3 C3 and ^ W W c/5 CO ~' CO o _1> Ifl J^ II si M 00 O C< IT) O c<^ O U-) Tt T"- M to IT) in ir> '^OOOC^OOOOwOOO^OOO CO 'i- 01 O r^o 00 c^ en "^ o) O cnao m o m i-i OO^vDM u->xr)0 O 000 C^O^O Noo O O Tl- O \0 u-> t-> ^ 00 (X> 00 00 oOvoOOOOOOOOO'OOOOOvO OOOO^OOOmiooO vooo O O 00 ■^c<-)^v[ M ON Tl- CT> rt t^ vO 6 d M d 0^ M d M 00 en ir> CO 1^ •jnqd[ns 'uaSoajifsl t^ vT) •Tf coo 00 O m ^ r^oo r> tn •usSXxo CO COO 000 Tf r^ OoOt-iO'^Ocoi-ir^MOinOC^ON OMTj-MMOMr^NOOwinTj-o 00 CO CO »n CO inm'^'sf'^coxn'^inininvnrl-Ttin ■* "rt 00 u->o in M in c^ CO t~^ 00 00 00 CO 00 r-- coco »n CO ino 00 ^ CO r^ Ooo in M CO T '^ ooOO'^O^M r^Minoo HI MM |-IMMMI-( '^ i Tt in CO CO c^ •^'^Mcot^in inr^'^ inoo CO 00 £ r^ N Qo r^ 00 a> TfCO 00 '^ M Tj- M M 00 00 r^co oo'Ttt-^ t^t->.r^t->t^ CO ^ .s a U o a .ti >^ fl cj oj o Js Q u Q 6 a 86. ig 5-24 7-37 1.20 7310 73.34 8271 829S X 86 23 4-59 7-33 1.85 82.27 75.67 "16.64 7467 7537 8097 8172 2 86 03 27 5 14 5-17 7-95 6.53 0.88 8008 8078 7827 8194 8371 8265 8370 3 4 87 1.03 l^-^l 70.04 23.71 7828 90 79 4.42 3-41 1.38 84.78 77-52 14.16 7829 7816 8546 8532 5 8q 65 4.62 4.62 i.ii 77.12 73-97 21.04 8026 S080 8459 8516 6 88 85 4.83 5-24 r.o8 7926 8434 7 8-, 5-38 5.28 10.86 0.66 7549 7731 7523 7736 7928 8278 7899 8283 8 9 ".5 86 19 7-33 1.20 70.08 65.12 "28 .'38' 91 40 4.51 1.28 85.18 83.55 14.12 8438 8441 8644 8646 10 86 31 5-07 6.97 1.65 70.54 66.92 28.04 7824 7840 8248 8265 II 82 24 5-13 10 95 1.68 74.43 71.14 24.98 7488 7486 7794 7792 12 84 08 5-53 10 •39 68.30 64.96 29.62 7650 8101 13 88 55 5-07 5-31 1.07 78.82 73.96 20.19 7973 7900 8475 "8398 14 89 62 81 4.12 5-55 4-59 1.67 86.16 65.70 76.32 61.36 13.04 32.65 7435 7820 7482 8326 8225 8379 15 84 9 64 16 87 52 4.82 6.58 1.08 76.28 72.19 22.23 7804 7840 8275 8313 17 83 14 5-40 9-33 2.13 7^-83 53.96 25.67 6368 6424 8016 8086 18 84 60 5.28 9.70 0.42 7688 7662 8043 8016 19 86 33 5-43 6.72 1.52 71.38 "he. go "27. '18 7859 7S71 8363 8376 20 89 05 4.90 4.38 1.67 78.73 71.70 19.99 7800 7842 85 ■■3 8560 21 89 55 5-21 3-95 1.29 78.46 71.53 20.44 7953 7978 865s 8682 22 88 22 5 -04 ^5-39 1-3^ 78.36 74.13 20.59 7992 8015 8444 8468 23 85 62 5-55 8 "83 65.90 61.78 32.22 7780 8288 24 84 31 5 01 9-05 1.63 73.74 70.46 25.28 7620 "7637" 7965 7983 25 87 39 5-23 5-96 1.42 77-56 69.7s 21.52 7674 7679 8415 8420 26 89 43 44 5 23 3.66 1.68 903 80.27 67.40 72.43 62.67 18.5s 30.75 7881 7700 7907 8670 8254 8699 27 85 5 S3 28 82 5-32 11.03 1.48 6825 ■■6899" 7837 7922 29 8=; r,A 5-52 5-50 8.33 9.22 0.91 1.05 7749 7527 7518 7538 8224 8110 7983 8122 I 84 25 65.49 59-72 33.19 2 82 25 5-48 11.36 0.91 62.70 59.55 35- 00 7420 7509 8286 7957 3 83 21 5-45 10.13 1. 21 60.83 54.43 37.14 7296 7343 7862 8032 4 84 45 5-43 9-33 0.79 66.40 59.92 31.60 7397 8095 5 80 95 4-93 12.81 I-3I 61.70 50.93 34-40 6424 "6478" 7556 7619 6 86 23 5-H 7.10 1-53 74.40 68.11 23.68 7567 7571 8256 8260 7 79 97 5.86 12.62 1-55 59-37 54.28 .36.95 7051 7019 7753 7718 8 83 32 5.65 8.75 2.28 61.07 54.32 37-72 7473 7571 8127 8233 9 81 37 5-57 12.03 1.03 60.21 54-56 35-74 7016 6989 7796 7766 10 85 80 46 43 80 5.56 5-34 5-54 5-39 8.46 13.03 8.92 12-73 0.52 1 .20 7750 6635 7678 6492 7622 6663 7763 6533 8245 7619 8183 7680 8109 7652 8273 7720 _ 84 80 0.74 0.94 13 H 94 64.95 53-72 30.12 80 79 5.60 12.51 I TO 62.30 56.08 34-25 6974 6971 7744 7740 15 85 38 5-23 8.7t 0,68 68.46 65.63 29.81 7752 7798 8133 8181 .6 85.75 5.59 7.66 1.00 68.50 64-51 30.26 7872 7847 8314 8287 17 8100C + 29ooo( H — -— ) 4- 2500S — 600W 228 FUEL TABLES. GERMANY C. Upper Silesia Coal. Grube Deutschland (joitesberger Viktoria, (run of mine). . Guidogrube Grube Konigin Louise Mathildengrube Paulusgrube Schacht Vereinigt Feld D. Saxon Coal. Kaisergrube Gersdorf b. Oelsnitz Vereinigt Feld Bokwa-Hohndorf Zwickau-Oberhchndorf Wilhelmschacht. E. Upper Bavaria Molasses Coal. Haushamer Large Coal Miesbacher Coal Penzberger (run of mine) F. Saxon Brown Coal. " Alfred " near Calbe a. S " Bach " near Ziebingen Meuselwitzer Revier " Fortschritt " Gnadenhutie b. Klein-Muhlingen "Greppen"' " Luizkendorf " " Marie Louise " G. Peat and Lignite. Peat, " Pschorrschwaige ■". Compressed Peat, " Hofmark-Steinfels " ., Lignite, Jbsefszeche in Schwanenkirchen. . Peat, " Ostrach " H. Coal Briquettes. Dahlhausen Tief bau Haniel& Co Hugo Stinnes, Strassburg Stachelhaus & Buchloh J. Brown-coal Briquettes. Stetnpel ' ' Furst Bismarck " Wurfel-Brikett C* Use, Bergb.-Act.-Ges. in Gross-Raschen-Senftenberg Wurfel-Brikett S* Rechenberg & Cie., Grube Mariengliick Stempel ' " Rositz " Gewerkschaft •' Schwarzenfeld ■" Stempel " Siegfried " Zeche " Waldau " K. Gas-coke. " Consolidation " (Ruhr) . Rhein, Elbe und Alma" (Ruhr).. "Ewald" (Ruhr) " Bonifacius " (Ruhr) " Camphausen " (Saar) " Heinitz " (Saar) " Konigin Louise " (Upper Silesia). Composition of Air-d ry Coal. c c A • t. c ^r ^ o ^r P X5' u •0 X m 1 < S: 6 71.90 4.56 17-37 1-15 1-.58 3-44 94.98 81.12 4.24 4-93 1.23 i.bs 6.83 91-52 77-79 4.85 10.07 0.57 1.67 5-05 93.28 70.60 4.30 8-77 1-57 2.28 12.48 85.24 7«.3i 4-70 9.87 0.75 2.05 4-32 93.63 73-96 4.40 15.1b 1.41 1-95 3.12 94-93 70.17 5-17 9-39 1.26 8.14 5-87 85 -99 71-45 4-76 10.06 1.30 8.91 3-52 87.57 74-63 4-97 9.60 i.bo 3-50 5-50 91 .00 75-95 5-35 11.17 0.63 3.68 3.22 93.10 58.01 4.42 12.02 4-B7 7-37 13-31 79.32 51.9-^ 3-75 13-44 5-31 17.12 8.4b 74.42 47-78 3.83 10.92 5-24 10.18 22.05 67.77 41.41 3.29 9.84 2. 12 36.26 7.08 56.66 35-93 2.56 13.20 0.99 45-33 1-99 52.68 44-47 3-67 14.69 1.72 27.13 8.32 64.55 ^7-16 3-39 9.62 1.66 38.68 9-49 51.83 43-37 3-25 17-54 1.93 22.85 11.06 66.09 31.12 2.79 9-42 3.87 47-45 5-35 47.20 45.40 3-73 10.72 3-59 29.27 7.29 63-44 38.76 3.66 21.27 0.26 29.14 6.91 63-95 49.31 4-4« 24.07 0-39 16.47 5.28 78.25 28.80 2.54 9-55 2.87 40.35 15.89 43.76 45-93 4.70 29.18 0.61 14.06 5-52 80.42 83.24 4-05 3-13 1.26 1.06 ,.6 91.68 81.96 4-15 3.14 0.88 1.77 8.10 90.13 80.85 4-45 4.82 1.19 1.76 6-93 91-31 82.69 4.10 3-6o 1.36 2.10 6.15 91.75 54-35 4.66 15.21 2.28 15-77 7-73 76.50 55-91 4.07 19.14 0.78 14.77 5.33 79.90 51-74 4.24 18.57 1.00 18.95 5.50 75.55 51.73 4-32 16.37 1.50 19.40 6.68 73.92 48.20 4.20 15-84 2.98 10.26 18.52 71.22 53-66 4-58 15-59 2.58 13.65 9.94 76.41 50.97 4.20 15-25 2.52 16.57 10.49 72.94 8s. 18 0.70 4.04 0.87 1.79 7.42 90.79 85.30 0.81 4.80 0.88 1-71 6.50 91.79 80.68 0.90 3-74 1. 17 2-33 II. 18 86.49 82.03 1.07 3.61 1.02 1-53 10.74 87.73 82.91 1. 00 2.60 1.43 1.79 1C.27 87.94 88.08 0.78 2.8s 0.81 0.96 6.S2 92.52 86.35 0.54 2.01 0.96 3-73 6.41 89.86 Dulong formula for calculating heat-units (Verbandsformel): COAL. 229 — Co7ttinued. 1 u' Calories of Calories of Composition of Pure Coal. 1 c V Fu el. Combustible. c c a! c 1 ^ c g, 3 U JJ bi § u s 1) 2 -a ^.i 0. 1 ^ c 'C u C 4J 2. t; a c4 5S^ "5 £ > 3 Q 3 -^ u 3 7<;.70 4.80 18.29 1. 21 65.73 62.29 32.69 6536 6881 6891 7254 I 88.64 4.63 5-39 1.34 81.46 74-63 16.89 7643 7646 8362 8365 2 83. 2g 82.83 5.20 5-04 0.61 7346 6671 7429 6662 7895 7847 7983 7837 3 4 10.29 1.84 ■■;r.;8" 58.70 26.54 83.64 5.02 10.54 0.80 . 67.82 63-50 30.13 7355 7414 7868 7931 5 77.91 4.64 15.97 1.48 64.19 61.07 33.86 6739 6804 7112 7180 6 81.60 6.01 10.92 1.47 60.50 54-63 31-36 6825 6801 7994 7966 7 81.59 5-44 11.49 1.48 59-75 56.23 31-34 6782 6750 7805 7769 I 82.00 81.58 73-14 5.46 5.74 5-57 10.55 o!68 7162 7292 5623 7169 7299 5623 7893 7856 7144 7901 7864 7144 3 I 15.15 6.14 56.50 43-19 36.13 69.77 5-04 18.06 7.13 45-35 36.89 37-53 4836 4851 6512 6532 2 70.50 5-65 16.12 7-73 55.13 33.08 34-69 4655 4710 6959 7040 3 73.08 5-81 17.37 3-74 30-35 23.27 33.39 3787 3741 7068 6987 I 68.20 4.86 25.06 1.88 26.44 24.45 28 23 2927 2913 6072 6046 2 68.89 5-69 22.76 2.66 35-59 27.27 37 28 4014 4059 6471 6541 3 71.70 6.54 18.56 3.20 28. 30 18.81 33 02 3454 3426 7112 7058 4 65.62 4.92 26.54 2.92 38.51 27.45 38 64 3722 3870 5854 6063 5 65-93 5-91 10.96 8.20 24.98 19.63 27 57 2800 2818 6536 6574 6 71-57 5.88 16.89 5.66 34.90 27.61 35-83 4285 4319 7032 7085 7 60.61 5-72 33.26 0.41 29.60 22.69 41.26 3261 3283 5383 5407 I 63.02 5-73 30.76 0.49 31.25 25-97 52.28 4331 4364 5661 5704 2 65.81 5. 81 21.82 6.56 34-00 18.11 25.65 2552 2578 6385 6421 3 57-11 5.84 36.29 0.76 33-16 27.64 52.78 3956 3993 5024 5070 4 90.79 4.43 3.41 1.38 84.78 77-52 14.16 7829 7816 8546 8532 I 90.94 4.60 3.48 0.98 85.60 77.50 12.63 7734 7804 8593 8671 2 88.55 4.87 5-28 1.30 76.35 69.42 21.89 7685 7616 8429 8353 3 90.13 4.47 3-92 1.48 83.92 77-77 13.98 7778 7822 8491 8:39 4 71-05 6.09 19.88 2.g8 39-87 32.14 44.36 5165 509S 6S76 6787 I 70.00 5-09 23-95 0.98 40.17 34.84 45.06 4947 4899 6303 6243 2 68.49 5.61 24.58 1.32 38.92 33.42 42.13 4659 4583 6318 6217 3 69.98 67.68 5-84 5.90 22.15 22.24 2.03 4.18 4770 4561 4788 4523 6610 6634 6438 4 5 49.40 30.88 40.34 6491 70.23 5-99 20.40 3.38 40.78 30.84 45-57 5092 5188 6784 6910 6 69.88 5.76 20. gi 3-45 40.09 29.60 43-34 4756 4725 6659 6616 7 93.82 0.77 4-45 0.96 98.00 90.58 0.21 6967 7057 7686 7785 I 92.93 0.83 5.23 0.96 96.25 89 75 2.04 6982 7071 7617 7716 2 93.28 1,04 4.32 1.36 95.16 93 98 2-51 6675 6716 7734 7781 3 93.50 1.22 4.12 1.16 95-30 84 56 3.17 6841 6851 7S08 7819 4 94.28 1. 14 2.96 1.62 95.41 85 14 2.80 6935 6936 7899 7900 5 95.20 0.84 3.08 0.88 98.30 91 78 0.74 7271 7268 7S65 7862 i5 96.09 0.60 2.23 1.08 94-34 87.93 1-93 7080 7111 7903 7938 7 8100C + 29000^ H — o" / "^~ 2500S — 600W 230 C en EU FC/£L TABLES. 3 - - NO "^ r^ o en IT) O O vO r^ r^oo O -* 't -f 't M C4 M O N r^ cnoo CO 00 N o oo rfoo o ■^ CO Mvo <^ <:> o M Nu-)0 r^vo o N ■-imC^OO'1-u^ONhhOc<^Oin Tt-i-rtcococ<^cnc^ cncn^j ^r, ^ xn a^ "^O CO '-I »- M O >_ _ r^oo CO c/j |-^ r^o coOOioOcJOooMNco t^co r^ r^ -i- N mo oo O r^o oo o n r^ rt- coco C>P< M cnci c^ Tj-r-^t<^ •qsv •J35T2M •jnqdins •uaSoj^ijsi •uaSXxQ •uaSojpAH ^ d d d d d d d d d d d d d ^QO r^ o^ o^ ^ r^ u-)CO ^ coo c^ o u-^O O •-1- M •^ •Tt CO c^ rt to M N ^ M Cl O o o o O O o o O o o o •^ '"' r^ O O CO n coo r^ 0) o o CO XT, i/) N ■* rf W en M CO lo o^ o^ CO t^ r^ in M M o M o J^ CO idO O O CO Tl" CO CO ino CO tt CO O ■4 XT) IT) tA '^ -4 CO lO'^rfrJ-r^TfT^Tt-'^Tj-rtTf-^ O Is <^ -5 ^S' f^ =q M E? .^ ii £ "S -^ -^ S N tfl ^C/2 ^ - ^-^ '7! • c/5w C JJ "5 CO si 00 M cnoo i-icnrtooo O O OvOO wco «r>o fcoc^cnx/>o^N cn^t r-.r^ir)QO M incoM O '-' c^ ooocoo cncno--, r->MO woo U l-H cnOMnOoo 'l-vnvo tni^voTj-r-,inr^o r-«0 MOOMr)0^<0'OiO'-t-Tj-NMOMOooOoocoxr)COt-HOC>cn coco t^r^cococo t^cocooocooooocooo r^co r^r^r^oocooo r^co •qsv •J3;bm 1 •anq dps d cncnlr>O^M^^c■*or^c^O '^ wr^TfM om cncno ^0 N 1 < •aaSoj^i^ CO 6 CO •^■oo U-) m coco mOOOOC^coO moo co ci O^ M « xnco ■^N loino 'i-i^N Cl N cncoc<^c<^coO 'd^o6d^'^M'!tcdTj-MN(Nc^odddddcddM 1-- en •n3j §Axo q r^(N r>.mcnM u-)0^o c^<>dvd 1-1 OMT) C>0O VOCO N a^ M CO d M c^* d M od 4 CO M M M M H-l M l-( •uaSojp^H 00 en "^O MOO iDMoo TfO eoiooo r^OvOvO O too O moo r>.coco O »r> m ID en M t->o cno r^ OO t^O d invo i^ -^-O m cq c^ cnoo H eg 00 Ti-M oi^coM Tioo r^M r->avooo cocoo c^ 00 O co 00mC^mC^rj-c0-*00rH0u^0^v0'^MOMC^M'^a^C4O>-'r^ rt-^md codo d cococoMod M cncoM copJ c>M c^-^'^corA coooooooooco r^oOQOcooooo r^oooooooooooo t^oooooooooooo > aNr^o^»nr-<>ritn 00 d d c>o d d M C^ C^ M M C^ d E r-^inTftnOOT r^ mi-HOOMcnO'^ 00 M ei c<-)vd M 06 en vOiovooOvOm CO , c .c c a E ;2 c .2 ^" 1 m *i c »— ( 1— 1 c < c c 1 c c 1 3 a; 1 g-i 'l3 =3 ^ il=J 232 FUEL TABLES. "o i c^ a^co vn a^ o^ O t*^ coco r^ m o en cno 1- 00 M •^M -i-M r^oo vocnooo or^o^cnu-iinu-io 'I'OO vn^^coo ow c^ -1-iHcxD -^qnO "h ocnii^-f 'l-co o vo in (-1 10 01 o^co r^ m t~^ vn r-^ '^o "t ^ 0>-i(Ni-icnO-i ci 040 tno tnmioco rt-t^vo m-for^c^ 0^0» oocooo r^oococoooco j^cocooo r^coc» i^i--i^i^r^r^t-Nr^r^r^i-^oo r^t^ •qsv i->.oo r^N o r^N Tf-1-OM o tnw ir>r->r^in'icncnr^r-»>ntnM m o m rt cn(Ncnr~^cnu^^^'i-r~^ooo^l-lI-^a^0^^cnOc^<^^cnr^Ocn'^r^Mooo^^ u^, r^rj-cnr^u-joico Mccoao O i-^o3 -^-co iri^j-cnoo ■^voo C^d^o rj-inr^ •J31BAV (-iMi-iioTi-NtncncnNcsNN'^NOju^ooooMf^vOooo^Mc^cnrj-cn •jnqding •uaSoJiijsi uaSAxQ u-)0 en O 000 r^ r^ O O O O^oo w r^ o >-i ci -too OOOOOOcoOOO •uaSojpXH Ttin'^-j-Tt-ir>rfTfvnTtio^r}-rt'^TfTrrl-Tj-rl-TT'^"<1-'^'^-Tf ^ t» "JJ ^ s 2 --^ ^ rt E S ^ t3 - r^ COAL. 233 O 1J Si •iisv •J33B^ •jnqdins •uaSojjt^ •uaSAxQ ■uaSojpXH O r^co 1-1 o O c^ i-i u^ O ci 00 O 04 >-i O O MOCcnc^MMON O r^ O cno M O •'^ CO 04 04 M r} O -^O XOCOM 1-1 Tt'l-CfjCO cooooooDooQOcoco ir> O '-I CO •^00 IT) ir> u^r->MNOooi-HM CO CO 00 00 CO r^oo CO en 04 Tf CO rt- en vO en "^vo 04 ^ 04 cn 04 IT) ut -rt- O o vo vo r-« 04 M d M 6 6 M O cn M o u->oo vo >■ o cn ^ cn cn o^ o U-) M M M M d O I 04 O J MM cn'^'^u-iin-^-^'^ 1 cn 06 CO 1^00 04 00 cn i-^ t--0 O^ M l-> N M d^ a^ r-> 04 cncd O^vO r^ r^co CO CO 2 cno T}-o 00 0^ rr •^ f^ M '^ T Tf 04 04 006 -^ irivd r^ t^o r^ r^ t-^ ^ rt 1 d^ 04 i^r^OOOOO)cn 000000 r^co d^M m"04 C>tAM 04 cn 'i- Tt cn 04 M Tf cn cn M M 04 U-) M cn ir> 04 00 d 04 u->o6 cn 04 cn cn 04 04 00 cn Mr^O 04 cno^ioTf OoocnMOioO'^ 04 lAo) cn r^od -4 r^ CO U-1U-) 10 inooooo M too 00 Tj- t^ cn tto 04 t^ m t-^ t-^O vri d r^ lA t}- OOQO lOO lOlDOO 1^-^040 1000 Zl ■^co xnco 04 00 •^ rj cnco r^ •rfoo r^oo cn U (U OJ ., CO ^ ^ fc ^-B ^ ^ S; S^ ?n -^ !iJ <" a; ^ >■ 1/3 C/3 rs li C ?* -< b >^ i^ PS K^ b* -if -S ;^ V- c .„ -, &.^ dn p^ fL, H H P :> §< CO M \r> o cnoo §-S II 234 FUEL TABLES. C T3 03 O w 2i o ii u e g s- • t:) 05 j3 ■ e- CO C CO ^i « « £ •c S O X^ o i/i O Tf o o COvO vO CO IT) CO a^oo CO Qo PI M CO M O i-i c^ O oo -^ c^ QO IT) i-i r«. CO O CO HH rf CO C^ QO ino T -^ m CO COCO vnco M tn r^ t^ CO -T '^ in O O O^ •- c^ ►-, hi to m N CO CO in O O M C^ CO N r-. 1-1 O <0 f^ r^ r^vO coo e^ CO r^ O CO i-H o \0 O CI c^ CO m -t O O O CO w O »n O O w O O "1 M c^i CO O CO O -1- CO O CO "T in in ino O O O •qsv HH CO ■'J- W P4 "^00 Oco O toco •j3;t3A\. •jnqdins Ti- CO to to o o o o o o o •uaSojji^ •U3S;{xO •uaSojpiiH o U O O oo in in CO in c^ r^ r^ rt w -4- ci CO in in in in in coo t-- O in in to O CO CO O -T r^ ^ r-> O O N in O N CO m O CO O O CO in w ino o o ^ O O ino r^ O 1-1 i-i ^ -^ CO rj- c o u •- a; II in O C^ in m -^ in r^ w M moo in r^o ■T -1- TT rj- Tj- r-oo in CO r^ O o r-. O O CO O W O O CO in O CO N m •I- CO -t CO in c> C> rt CO M O CO CO O ino in '^ O -^co O CO inO in in ^ -^ in in CO " in 1- O in -^ \r, -rt \r\ ino in E ^ 2 o o p:: Is 5 CC (D C 03 •? b: w cd -r" J r' ™ o O hn <^ i_: T3 >- rt 55 3 C -^ - •2:2 >.' CQ -i— • — ■ v\j ' rt gJ (U o COAL. 235 o o u ^ H Ifl ^ u o r-^vnr^M (Nr^CT^cnoou-iooior^ooooMi^iriooOoOMf^r-^ NmNM (NMNO'-iNi-iNNMMi-ii-iOOONi-'OC^N ©•^"^IN c<^vr)MMr^Oir>'*u-)u->OC^Ocoi-iOOO->^00 ■^'l-QOM oou-)Mu-)mO'^cocot-iooi-iNC^O~'OaoOini-in r>. 00 r^coo N cor^oooo cnOoo Ooo winu-iTituno^m O vrivooo r^O "^M r^oo cnco inoo tr^Lnc^ 1-1 o ■^ >s cj -^cnvj-M cnrtcnco(N cn^rj-Tj-M ci-^co'^tj-w coioo O 00 100 o: t-t M ti-)0 C»ntoci u-)c>Or-^ o o r^ vi-> c? coc» 00 ocn-j-Mvcoo cnci »o r^vo o « T3 tn cfl o 1) U^ oJ .^ O OJ 53 T.^ .§8 e 03 TJ 3 C IJ TO Co . ..-. n. _< > __ 5 §.5 ►:i^QmcQ O O J3 e C a, O _ .. JD rt OS Oj ra x: ^ mui 236 FUEL TABLES. O jU c en II o •qsv rt c « «i 4; :!i U S g CL P ^ O •- NaMaMMMI-cl-iC^I-l a e^ M r^ r-« Tt- O O^ O O O r-N f^O CO o >-< -t 00 000 O r^ O O O r^ in (^ N 00 O "^ i-i •1 -1- OM^ S ess o o o o t: 'CI , o c^ c^ =! OS 5^- ■s§ •5^ o •;: o^^ cu 6 a 03 rt s s CO ^< M ^ "^ rt o o o o o OS E "i u a: o COAL. 23? I •i a c3 1 S'-S 2 >» h^ • c . 3 03 tfi « < -." ^ CO v" 00 r-o ooc^Tj-r^w M 00 r^ (N GO '^ i-H M I-, c^ -r H vn CT^xn r^'^c^Or-^i- u;^ M CO w 00 QO C^ csi r- x^o m '-' M HI MM M l^f^ X, u Tl-O rj-xn incof^OOO eno inoo m en m vr 5 in M vo '* -^O in en in •^ rj- en c<~) en l-H M 000 COOO M 00 MO •qsv M N 6 c> N 00 M 0^0 inoo en d d >-! M 00 ■^0 M cn cn f^ CO 'Tj- M in M C4 M MO HI en en M en M en en (N •J35BAY c^ c<^ OCC M Tt f^ •jnqd[ns CO Tt 6 d 6 1- 00 00 N ^ i Q •r J. c/- s ^ . . . . ^- P^ r; - ^ c/) :2; :zi :z; :z; J^ Z < ^ <^ rf 03 H c3 iz; «5^ h C M CQ ^i U1 :^a 'C o KU U O^OOcoo Moo O r^c<^N oor^r>.M coo O r^o n m J rt rt :tj ^;] UPQU CO o O x^ en 'o U-) d moo M \c O o o o CN o cnvc CO ):; l?i o I O M >-( c^ 00 OO M o U-) C7\ OMO -f tOOO -f ^c^ C> O-'OO OO -O CO rfcou-io cor^a^c>oo CO CO C^ M M CO ci t~-«oo cocO'^OOOOOO >-iO O O^Ooo u-)Ooo O \nu->voT:fu-)'^TTTj-rl-'^ ^ < ^ o Q H O . o O M w u — -3 C/l < < > o ^ o w ^ z w q O ir> o vd N vd o d> oo CO pi CO in d U-) O CO O "^ c^ N •^o o6 CO o r--oo r^ CO ^1 CJDp3 ^^ f »-■ (L> >-■ n (11 cj re O _ a.-d g aj re C r- ^§ i -^ ^ ;^ > C C M cfl «-< O o ex, > O cj O COAL. 239 - z z ^ CO en CO -^ -^ 'rfCO O NioOvOOOO»n 0 O inoo M 00 00 x^oo CO r^vo lo-fc: f--^f^M i-i(X) O^ O 00 O M fi CO U-) i^ f-, M r^fJO ^■^w c<-iT3--rcj 00 U-) O CO O f^ m rfoo u-> M coMoocna\ooi-Hoa covoo r^oo r^inh-i c>voco r^r^coco ininsD O^ocxjo •qsv •jajHAV O O 00 vC O >o •jnqd|ns •uaSoj^i^ .uaSiixQ 0000 N O i-i tH o o 1 a^ u-)0 r-. ") M '^ N 6 I vO»ncoi-iOcn"ii-i I MMMMM cncnj •aaSoapXH •^uivninvD'^'^m ■^vnrt inu-juo-rj-m'^'i-Oinccrj- vn o CT^ O vnvC en 5)0 ^ 1 r^ "/Sop, 0-- a,- en tfl W ■In r^ 00 G O O C5j o tn '^ ;3 erf -• _. rt rt !> cJ 2 £ 3 (u o j •uaSXxQ •ug^ojpAH i-i IT) h-i M in O^oo in (N C^ (N TtO OOO Oil OM inM -^ in hi vo C^ r^ OO (N O t-i o OO C4 en inin^inTi--t't'1-co-t^-1--r-1--1- OTfO'-^OcnMin Olco in-i--rm*1-h- in CO r^r^r^r~r-^or--r-- •qsy to O W CO M O •J3;bAV c^ 1-1 in M O oo HH rj- CO T O O M o O O O O N CO CO r-^ 00 O O O CO 'i- a! CO in in inO O O in t^ O C<> CO -+ o o o CO 1-^ in 't u-> 't O^ O^ O** 00 f"^ f~^ _4J > 1 to O -^ r-> M O '^ (U biO-^ r (u s_ :: a, 3 I ™ C3 '"^ en y Or^ 2 = 5j jj^ -< -^w coi-H or^coco 04 M c7>o cocococoooooco t^r^r^i^occo r>.r>> r^OMO>-iNcoOcoc^ooi-iMr^O vO i-i tninr>.vO ininco or^oo i^inoo in M r^ Oco CO r^i-»r-«o^ocot^ ooo ci ,ci -35 o :;: inoo O en o O ";;;" in n n r^ 8 04 O 04 r^ O r- c^ w coo O -^ CO o « OOO a O CO ^ N N 04 N '-' ^ '-' ^ CO 04 in in oo oo r^ r^ M CO in -t 04 CO O 04 O r^ O in O oj i^ r^ O -^ HI O oo r^oo o ^ O in O i^ r-^ ^ M O r^ Ti- M rj- coo ;> CO M re o -h 't -t \n in n 04 oo «n in in in in O oo O C^ M hI T o W O CO O M M M Tl- 04 rfoo 04 O O O M m in Oco HH 04 O i^ 04 o r^co o r^ CO O O coo O O in'^inTt'i-tninin in in in rt m r:)- rf Ocooo4 0r-^0i^ CO CO M o u-)^ ut^ O i^ CO t^ -^ r^ CO CO M coco h-l M CO 04 MO coin-Tj-M O oo r^ £^ r^ 1^ r-^co oo CO ir> r^ CO r^ r^ M r^ t^ i^co i^ r>. f>i O CO in -1" 04 n i/^) in Ttcooico 04 mrtrn incc M hi r^ CO CO 04 r^co o 04 CO r^ r-- coco coo coco oi 04 COCOCOCOCO04 CO ino CO o O "^ r^ CO CO CO 04 rt CO CO OOOOi-ooiC^ M r^ Tj- r^ CO ■^co m O >^ M in O "i^ m COAL, 241 O _4J U5 S^ •-'XI u o OOOWvOO'*^ fOOO Tt rtoo U-) TtOO U-> I-^ f^ l-H T^ u-> coM-rfMMWMe^oOcni-ii- 10 cnvo o r^ M 00 vr> M ■qsv TtiriTd-r^Ti-cOT:frf'^u->^c<-)'^ coooO^t^MCJcoin •J3lB^ ■jnqdtns •uaSoj^i^ •uaSAxQ •aaSojpAfj N coo O en coco o t^oo CI N o r^QO C/3 5 O O • r-< ID ^ w i_) Kr,^' U2 aji_LJ,_L ro > _1 AO U ^Q W Ph S S U C ^ rr- *-■ ^ '"' C C3 IC (L) 3 (U U rt .V TOW C r"^ <^ .U c/: > c^ > > 242 FUEL TABLES. O 4i ;^ -.•2 "5 « ^^ ■/) T^e •n o ffiU •3 ■qsv M31BAi •jnqdins iia^Sojiifj •uaSiixQ •uaSojpXH vo«DOl-lcnc^MC^^^Qor~^ rocncMcnr}-cii-HHHMO»c<^'<^ mo O invC O^O »r)C» '^ O r^'i-i^c^r^O •-• cnr^N coco cnoo MOcoOf^^Ncic^cnvn u-)co OOOc^inOOO'-iO C>co O O - t^ O "* ^ O w (N c^'i-r^6c5dd(N-oo CO oo o^ O^vo vO O o r^oo _2 in • s > u > H s cJ5 ;§ f-^ cJ^ U COAL. 243 'c tn o o o C^ vn-st-O^N o -^ -^ a M r^oo 00 M c<-) r^ Tt en en iH vO M M M cno N 00 c^ moo t^ N CO CO CO CO in en rl- rj- CO M M M M M M M 1-4 M N N inir>r^cncnri-M o^ M M M IH W M M w c^ in cvi OoO'^MincncoOmiHWOinvOinNMOOOO incnrfm-Tl-inrfinN inr^o M en invo O M r^ i>. o cn•T}-t^lnG^c^N r^'^r^oo "^inM cnr^cno^'^f r^r^t-^oo r~»r^t^r^vOvOvoocoQooo t>-r^oovo m O vo in t^ r-oo t^ in O r^ en HI t^O 00 t^ •qsv MC^N'^'^enwinMcn^MOO'^MOoovOO enen ■aaiBTVi O^'^M cnc>OinoNco TtencniHCjavo 00 t^oo o •anqd[ns •uaSojiijsi •uaSAxQ •uaSojpXH O Tj- o^vo M c>om cnM r^in ^i-o d ind HH r>.'^(>dod i~^cni-- O^ O c^od ino cni-< cncncnN cnenc^ cncnw cncnw n cncncncn-^en OO^OC^H-wi-HOHHMcnO r-^00 inO^MO^Ocn MinO^-i c^ONi—MOCT'OcnMTtooOcnoot^invoooinin h-i-ic^o enC>^^dvd^~•6ln•^d^. c>odNO(>inowo6N dcJOO to'^'^inuiininrj-'^encncnoo mininin*^'^ inino m O cs o o 'w' > 1^ <2 ;:^ o -tjn > cd ..S CCi ^E^^ ^ — w »-< . : ^ ■::: • "^ § -^ Pi ^ o I--- o 244 in •t; W < H u HH :z: Di o 1— 1 ^ h-^ < o »■ t^vo ■^ fl NO N lOOO lONNO ON-^t^-^O n-. Tf« roN ncN HI onO 000 O O It- U-) .^ m On t^ 1 *<*- r^NO NO lO i/^NO 00 NO Onoo lo •<^ , _ . _ - . .N T» ro o>NO On tNi I NO NO NO r^No r^ t^NO r-NO c^no no NO ro -^ On Tj ro OnnO On -I- On r^ moo 00 ~,VO NO 00 ■«- r^NO t- t>. f~-oo toi^QNOOo ro-'a--*i-~- -!}-no •<^ 66>^666666666 -t \r, O ■u-i \ri u-i O O « lo-^i NO ■<)-ior---<«-ONiONNO rom( in N r^ Tj- Onoo o t^ O no O < NO m N M rooo NO r» N oo ►- n NO mONtNi " rr, -t- t-~. -t ^ -^ On On « rONO M On OnOO " 00 (TN N IT) lo N moo o « HiNwHiNNNMN lONO ! T^ in t~ 1 mmin- On« r>.Tr-*ir)ONmir)mo 00 On -"J-nO •* -^ N O -^OO ro M C4 m ONO >A u^ t^ '<^ TMo -a- ui -0-00 ■<*■ lo -^no ui i*- -a- -a- ■*■ U-, m N oo m m t^ -tea oo t^ - m oo •H i^ONN ►. o\ioONvoror>.t-^N MNO (N ON N M tx N N O'NO N o\o met t^o-« tv t^No 00 (^ tv t^ r~ t^No tx t~ 'a- -'I- 1/1 nSnS 11 t-^oo o> t^NO • • «- • ■ D- _ tn o « ■ O u : o > wpau ^4^ di _ 3 o o'S c. rt ... t, -, '3 '^ 4^ 2 • ■: 9 o o O (« 00 O O ■^ O M O O CO O O •sauoi'B^ CO in CO <.•) rf r-^ 0^ in in Tj- •3^03 •aaiBM •qsv N O o^ o d 4 •jnqdins •uaSojpXH ■uoqj-B3 g . J "S 1 - 1 M 246 FUEL TABLES. C/3 Ah 5 On o nxa in IT) in CO CO CO CO O in O O 00 00 CO c) en ':^ O W O 00 W O vO en CO o ■I O O •S3IJOI^3 in CO CO O) O 00 in Tt O in o^ O 00 en 00 CO O O CO O O r^ O -^ O m i^ a Tt u-> r-^ in O in in vo •J3JBAV o O M 6 o •qsv in m d 6 •uaSojji^ •uaSjixQ uaSojp^H I-^ M (N (N) CO en c^ ►-I C4 O' M in •^ vO vO vC in in in CO CO vO M l^ CO CO en •H en en in ■aoqjB3 < c p: s. c a; s bJ3 B e 03 p ^^ O rt ^ C ^ ^ ^ 3 ^ OVEN COKES. 247 xn W . ;^ < u ^ (z] ^ ^ w < > ,5 •5 t* - o <: u O 4> C en jeU M N r^ ^vo M Tj-(N cnMoo Mvo Tto CO O CO '^ t}-vo en iDmc^N cnr^i-H o O cnMvo 'i-O c^o o r^ 10 voo r>- OM cn(Noo om r^c< tncoo^cnc^co rr-^cni^ocni-i ooOOOOooOOOOr^ooOOO-Oa^OOOOO t^cococo t^r-»i^ooco t^r^t^ooco r^oo r-^r^co t^cooo •qsy 00 N o t^ N CO N CO r^ M •J3}B7V\. 000000 •jnqdins O O O O N •uaSojji^ ■ugSXxo •usSojpXH O M o o o o f^o^ c3 o - - ^ '^ — o ^ bjo C ^ cj J3 o 1^ ° o O a^oo CO CO CO CO r-*oo oococooocooo r^r-^r^. qsv vO xor^i^mO ■^vno coidn •aai^Av u^ r^ N vO Ti- vO o o tnoo ^ ^ '^r N N ^Tt^T^r^ •^ *" ^ M o 't ^ o o tn o o N cn o o o f> c^ CO CO oo r-. r^ o o o O N \n c5 O •jnqdins •uaSojiifj •uaSXxQ ooooooooooo •aaSojpXH w ( ) vnco en N < C< M N N CO en Tf cJ en o o O O O -)-co O m en r-^ ^ i-> N en o o^ OCO On ir>vO N t^O O G^ "^ O O M d 6 >^ 6 6 6 6 6 6 CO u-)co CO en en N mco O en O m o m O m envO m ^too m vr, ^ N '-' > c3 C^ r^ ^' cs 5^^ 6 '> CO pq rfl O ■pi £■■1 C (J) G G § 2 O OVEJSr COKES, 249 xn W t^ o u > o o j; C tn « o •qsy JSl^M jnqd[ns •uaSoJiT^i ■uaSiixo naSojpXfj p M 00 vO Q ■^ CO M Tj- N N CO H »r> W N cn Tt T^ Tl- Tf Tt -t •^ Tl- '* •^ -^ ^ Tf M ■^ '"' •"• •^ •"" '"' ^ m M c^ M ON M IH c< u )H U-) >-( M N M CO C> 00 Q (« 00 r-^ r-^ X^ t^ CO CO oo 00 U pq •5 =! 250 FUEL TABLES, •qsv •J3JBAV •jnqdins C/3 o < pUB ■uaSojpAH i-OOccOOc<>-cTfOc»r-» mc> ^ -t Tj- Tt rf Tl- vO Ooo iicoi-hOOC^wcoO idO oo r^ r^ i^ r^co O^oo O co O c^ ON N C<^' IT) l-l N d d o M .2 g c/) cS '^ C/J o ''Si s, kJ •^ Ci. a, D ^ P (U o ::3 ° Cj O-l.' -^-^.tiT^o-g^g og C/2 Qi -2 ^ 5fi3l ^^ OILS 251 o 1 |i o i o a. c J". . , . 00 § p^ f4 < Mayer Stillman & Jacobus ■^OOOooOc^^'-'inO'^ Tj-co O en t^ ir> ^ O < N O en M M o^ -Ti-oo vo r^ c^ CO o c^o en o i^ O c en ■* O M f^ '^r%'^ CO OO^M mo irirt enco r^ u->a oo cxD t^ Ooo r-H G^ o o^ G^ Oco o-^ o^ o c^oo co o C DOOOOOOOOtn :>^r^M eno enM oo DMO T^ln^^r^MO O 3MOOOOOMMO -IWMCSIMMC^MNM Cfl o 5 O en en N 0\\-< en vno ^O ->TtcoocoOwcoi-iT^-:j-cncoOOcxDenoONC4 0^ t-i c^ oo cnr^oo O OO w oqo co r^ rt ^too o oo ^ en •'^o u-> r^ o w OOOOOOOmmmOOOOOOOOOmmmh-imOmmc^m c be o 2 d M G >> X O ■<*ao N en O N Ti- M o en N ei M M < < IS o iNONTi-t>soencnw r^ enM«nMNMO-*en d 1 enMoor^Mi^MNM or^O oo O'^'^tor^r^oo ^- a •<^N cnenenM enM r-^cn enTfTj-enen-^en-^u^encncn c' u ui en O o ci •^ c^ voo O o en OO c^ enmiHOOM en NO tnrt-TM^4-0 6 en Qooooooooooooooooooo en rt e^ rj- Tf eno lo O en -^oo ejooooooooooooooooooooooo o a to M en w o o ^°° ennoor^ ocoo I'oO t^OOoo r^Tfc^oooo ooNO l<^ "^ *^0 en en oooocooooo ooOO O''^ ooooooo oo ddddd 6 6 6 2,0 * 6 6 6 6 6 OQO O 6, .2 o a Heavy petroleum, W. Virginia. Light petroleum, '* " " Pennsylvania. Heavy petroleum, ** Ohio American oil sold in Paris " " heavy, < ' *' "refined, " " naphtha, " " crude, " Heavy Pennsylvania oil " W. Virginia oil Shoshone Reservation, Wyoming Salt Creek, Natrona Co., " Oil Mt., Natrona Co., " Newcastle, Weston Co., " Little Popo, Agie, " Lander Oil Creek. Pa 8.1 CO O 2 g >, o 9 < If O u-ivo MOOr^OOOcoOOOr-^OioOcooOOcoi-H tj M r^ cnco i-ii-ii-ias(NOvOO^ OO c<^ T^ M a -tvo O O i-i C^ Tto »^0 -J-ir)ir)00 c^^r^rfTM c^m cno -1" m c^ m vO H oo r^cococooo Oco Om oo^C>or^cooooo (n OC O^mco m «) OcoOoov/^MfncooOOOOMcncn mOOOOOO i-( Mvococ^t^r^c^ _o ooooooooi-ii-ioi-iooa^o ocjo'-iOi-io "rt M MMI-HI-Hh-(l-(l-(MI-i>--. r>-. r>-. i-l 3 J3 a "s C/3 C 4J tn bx) M o d g c he Cnu-) OU-)MMCSu-) o wTi- o■^^dMM^ "^ Z o CO tnt^M u-)MainM>HO^ '^oo i-I 6»j^ci c^oMMdindpiN c > -a rtco O en M vO C>vO u-jt^qocnqqwrf Oen t^ c> tntHd^enNwaMciMcJer, p5M-j-Md con m to c o o J3 O oo MNcoOO'^iHir) co-O M o O w cOvO m t^ c3 Ttou^oNinr^-i-r^r^'dO'Or^-cAunr^ OO r^ ^j- oococooooocococooococooooocoooooco oooo oo oo O M 01 M M in -+O0 'l-O CO u-> Tj-oo oo oo oo oo i-i o^'^ r^oo ccoj ooioc) oo oococown r^ Ooo oococo ooo ooo^o^ O ooo^OO^O^ C/5 d d d d d d d d d d d d d d d d d >> ; 1 S c c« . S s ►^ 1. 1' Pi; o ^ > O 1 ^ 4. o a p. c "^ a. a )C/2C 17 > > K PC C 1 |i II UPc: > 5 c: PP 'c > > > 1— " C c c c: E K ''X. > > d >, 0) 5j m D NOOr^-OioOOe^^c^vOOOOOO^O coMoot^C^OOioOM •^00 O^ 10 Ooo M h M Ovo cnmt^c<^o M M Or^O OO cno r^co i^inr^r^vo o^oovoo 1^0 i^r^oo CQ ui •-< '^c«^'0 c^o cnc» w cnco cnc» oc-O ^ ir^co vTi c^ CO M MO •^co c<-) (N r-^ '^00 m O^cnOOooO Omo ONC'-irfTf'^O 0> O^CO 0^ 000 M OOO OOO^O^C^O rt IH M M M M u ^ 3 r-N, J3 00 3 "5 en 6 G (U bfl w. *^ 1 V •S C be ? s u-> , U-) kM M M M t^ 4 d d >> a: d * % en r^ r>. On 00 d c^ CO c4 U-) tJ- CO CO r^oo CO QO 00 00 v.* ^ o^ C/3 d w . . . • c^ w . : -1 • G C • . a;H \ • . • t« oj /lU . m • t: bJD . . c t ' Al • St3 , — ^ . _o .< • •^:s ^^ " : ^S^ : j^i i^-.l^ . i > > 0. "^ a. £ 'a t •1 < £ f: c c: E 1 11 oc Ozokerite oil ... . Heavy pine oil (bli Blast furnace oil,C H t^ ■u •- s 0) a, C/2 >> 'u Johnson Bunte Mahler Slosson rt M C^ CO CO CO C^ U-> IT) M ^ M CO rj- < 4vd C >> CO d d^ "5 00 x^o M CO r^ co\d r^co r^ > 00 c a c 3 cJ c ^ 254 FUEL tables: ca c c Ul o < Slocum R. Young H, Wurtz E. McMillin E. & M. Jour S. P. Sadtler F. C. Phillips S. A. Ford S, P. Sadtler Morrell << Rogers Anon J3d -fiMa MO-TC^Oi-ia)OOOoooOu->MOc<^co>-'0 r^oo n w n- OOOOOOC7^i-'000>-icoOir>OOooaDOOC>0000 J9d S3U01B3 Tfi-Hco i^oooo OO O cno '^M M M Moovoco o oo^ ct>oo o Oco M r^ rj- O m inco lo c^ o^ en i^oo cnvo on ir>c^ c<^mior~^f'. ON o o CJNCO OOO OnQ^OOoo Oniocnqn i~^cc co oo oo C^ O^ O^oo vr, CO O vo 1-1 h-i CJ i-i 6 d d d uaSojii^ c<^ N en CO -1- •^ en CO en ?< CO •uaSAxQ -1- '-' O O O O u o o o o o OOOOCONcn O lOOO vO en m o d d d u o en en o o vo •siuBuiuinui ■*H*D 'auaiAma O O O OO o '^ o o •^H3 'aunqpi^ •uaSojpXH ON en -^ (^ Ti- ON o o o c si.i C O C3 :3 2 . c ^ C D > Of5 5. a 3 *-; CJ c« a „ ijr .ti oj cd <'] -— ^fL,PL,u.i-i qnco m mcnr^o ■^O O O^oo O^ O 0^ G^oo oo 0^c» O^ O^ (y' moo r^ vn in vo O O c^ ■^Oiom'^N M i-i u-)0 'N^O O r^O M o O^cnoo i^r^r-^ O^ r^ O O^ O^oo CO oo OCX) oo O^co MOOvOrnvn u-5C>0>-i r>.vo o o r^ ■^ o^oooo ooo O O O w O O l^vO M O M N c<-) 00 rj-o .1 o I: :: - :: : - K rd ^ o s- ci ^ in: o g ra to ^ ra 3 - ^ ^ J2s6 FUEL TABLES, ml I S ^_ o Q < w G 5 u HUH J3d 'S9UOIB3 CO O M >^ C^ M OO r^ tn M vn M M O \0 "-O "^ r^cno iDinoOOvOOOO r^ uo M r^ c CO vr^Oi^c^^ Oco £01— o^ \rt O^ O ino r-»^Mco cncno O^mcnc^ c<^vo m c<^ i^ 'I- Oco r^ r^O coi-hOOO'^'^"^ m ■^ O O CO »r> CO too M vo a* M M vO CO ir> CO vO \r>\C> O vO O •aa^B^ < u s w < •uaSoaj!^ lo OQO vn o M CO «N M od M O O m w c^ M CO r^ CO CO r^ 4-o6 d CO covd CO h4 o w O in r^ i-( M M ino o '-' ■* d CO 4 e^ in M •uaSXxQ CO M Tt lO d w d d CO '-' d M d d d d o CO r^ CO MM d d d t/i < •apixQ D!UoqjE3 o oo CO O O O M ^ HH u-> CO r^o covo o O O -too rf- CO i^ r^ in vo r^ d 40* 4 4 CO in in o 't r^ in 4 d^ 4 4 4 4 .-J < c •ppv oiuoqjH3 O O vO CO CO «r> O ci M d d c5 M O M M O O -I- c< N r^ O CO Tt M w d M t-H d )-< c^ CO Ml CO o o o w CO CO d M •siUBuioiniii M O CO O CO lo in Tt ■4- d Tj- CO «= O u-> ac r^ r^ c» M O fj M d sd "^ in O ino CO M r^ r^ t^ r^ m c> 4 CO 4 CO 4 4 O m M r^ inoo N M C^ in in U-) »H3 '3u-Bq;3j\[ 1^00 m O CO 1-1 CO CO M vd d od vd ^ CO "Si- CO -^ M CO CO O O r>.vO CO coo w N in i^ od r^co* d^ &^ in M CO CO CO CO CO CO O e< in o m d^ ci coco d o CO N -^ CO 't CO "uaSoipiH "^ C> M O N d d o6 o r^ vn •^ Tt ":}- u-i CO d in in O O Om CO in '^co O ^ m 4 d^ r-' in 4 ino CO CO -^ '^ 't ■^ '^ CO o M r^ O M Oco o *i^ M d i/i d^ hJ 4 "3 ■^ 'rj- CO in rr m o O CIS . O .2 S a s 1. 1^ t/3 fc-H u ^ "t:i o) ^ o « ^ o - C '^ C '^ "5 "2 us •aooji3tqn3 a9d -n-x'e J3d 'S3tiO^-B3 p9H3jnqdins ■uaSojii^ O Tj-r^tnM co'^c^ O iri 00 N o en M o o t^ too i^ 00 o t^O woo cnM ocni-i Ti-N c^ o lof^r^ cnoo m o o o 00 •aaSAxQ M O M N M d d d d d 0000000000 •apixQ DiuoqjB^ 10 00 o r^ "^ iriN u-)cncor-«Tj-vO cncncou-^o •*enir>'<^Ti-vO O •ppV DiaoqjBQ OOOOOOOw O CO o o o o O O c^ O O •sjuBuioinni cocoes O •^cor-i'^r^r^^'^Nvo ■^cocomvno ■^00 cn^o u^ •usSoip^H 000 cno^ooo ■^coOvO r^Ocou-io O coioO coooo cocoo woo in^cncOTtTf^'^'^cn'^'^io'^'^ininTtvrj^rtco^in'rtcoM a : o do c G w 13 > ^3 WOOE o U U <^ o c Pu O .> o G :: :: :: W ' 1) o ^ 1-1 cu c a; H tA! "Xi "Zj _i-| -G >-i b/3 - c/~ C c _o 1) - 4i3 £ ^ T *J J3 n HH K CO :/: o: o 258 FUEL TABLES. J3d 'S9UOIB3 < o H •uaSoJiifsj •uaSAxQ "sjuBuiuinm •3nBq53i^ •uaSojpXH G c O rt (/5 CO "-^ t« c o .i2 9 ^^ o ^'"t 5 . j^^ p:i W W Ci^* ffi 'o c vOi-i '^rt--fMMu-)cnO>-ic<^OO^coOr^>-i O ooo H^OMOc^c^-coTrcnoo^a>coooo'^ o CO CO vO IN CO Tt COvC (NOCOCOCONC^COCOCOCO '^ CO a^c^ r-^Tt'^l-w Ooo -tc^ OO -to^HH r^ cOu-)COvr>i-i CO-^O OO'^C^ NOO O rrco r^oo O t^ O OO O O covo r^o co co oo i-i ir) Tf bjoo C fa O ca •^3 . .rs ^^^ S ^ I o S^ ^ o G . G • 9- S •1^ ^ : CO G . G "o 'o cJ ^ -------::::- - Dh ^ i-^ O O > ctJ ^ >- - 'c - G O - o o o AIR AND WATER GAS, 259 O >H vr, •— < *- 1 3J 00 C 00 SS 1 >. 2 S j^ ^ Dr. Greene F. L. Slocum F. B. Wheeler W. A. Noyes F. L. Slocum H. W. Wurtz E. E. Moore W. A. Noyes Jenkins [& Schi Shepard, Bruck Smith 1 < Shepard, B & Schim F. B. Wh( ' E. E. Tayl CO r^ cnvnM r^Ocn'-'inMMooTi-o •joOjI 3iqn3 CO vo en c^ OOen vo ino^r^Mi-i cnoo 000 J3d -n-x-a r^ i^ t^ cTi M t^ en r^ cno en en t^vo »-• en en en 00 c< (X) \n rf OMOOOmN eno O •J313PM 3iqn3 00 r^o 10 o^o ■^00 r^O r^f^T)-0 t^ jad 'S3U01B3 0^ M 00 TtMO w MT^oooa^r^cnMt^M vo r>i vo en MOW r^ voc^jvoc^NOvOvOMcn ffi 8 8 ^ 8 c4 i N 00 M ij-> M c>o M ■^oo >n en uS \r> en cJ 'j-d en eneni-id^Ttrtcnu-)d'^ oc C vO in r^ in ^ r^ uaSi^xQ d do r^ ■rr Mcnenwi^o^ inen d d Mddddd ww ■2 '^oo 8 W Tl- un MooiT) ci wMOOoom 00 a ^ en r^ TJ- cq 10 M d C>od d d in M* vd en -^ tJ- N N M ■r)- ^N-'t en woiMn-cnMNMMw 1 N in 1 < ^o^^NOen r^ d d ci d enc>'^TJ-«:}-eni- d* en en en m TfMin en tn WTj-incnenen ». . ». .1 N.J City anch a,' Pa Ex Oil-water) lue Gas) Exposition, N Louisville, Ky generator gas). riched) It.Vernon,N.Y onkers, N. Y. d.(coal& water , Boston, Mass Hoboken,N. J )ledo, Ohio. . . c .2 y City, Island ng Br delphii S5 w : :^ •^H-l ! .. .p4 position, owe process ew York G Y. City, 18 ose-Hasting (from soft c ose-Hasting ( rong process erre Haute, ^ilkinson pr< all process. s a] • • oj rt ^ h-1 H^ h4 ^ '^ (^ C^ ai b^^ X" 1 26o FUEL TABLES, < ^ O t— I "53 -w . ^: . — § c<^t<^cnO O >oc< -1-c^ r^coo< com n m w o c^ cninir)inM uaSojpXH pa^jajnqdins •u3Soj;i^ uaSAxQ MOOt^r^O*^ M O O w O N o •apixo oiuoqjB^ ■^ O 00 N O^ coo od N M M HH O N -4 4 C^ CO « -' u-)co •^vO r^ r^oo o OO in uotor>.i-< u-)^ cJvd d^ •ppV oiuoqjB^ O O M O "^O q 00 rj- in 4 rf^-U-)!-! u-jcod >nN C^vd •sjUHuiuiniii o o o N d « 6 O q o •soaiAma o 4 c< d O vn O c< O i^ O 'I- M 00 u->0 oo Tfcoc^ M cot^44- •auBqiaH CO M d usSojpAH r~> r^oo 00 QVOO M Oo' o d IT) oo O W CO vd o6 od u-> coco O r^ O O coOoocooo O M O O MoD\dd^d^dd^^Md o : • • • : •. : ". T3 . • c 1 * -2 • \ \ atile ngla ^ COh n ■ W N • > • c ■^ • c •1 S O >H -Q ^ 3 >. o ^ S-i U 3 N 3 M >• -- - St. G (after at Ca Mirlv o <^ " OJ rt •^^ 1 : . : . S :: :: .£ ^% H - :: V. V. >. " " c _^ G 05 O J^.o; <; pq Q u^m AIR AND WATER GAS. 26 r < < s I Oh w •5oOjI 3Tqn3 J3d Xl'X'e jad 'S3UOIB3 •uaSojpXH p3313jnqdins ■naSoiii^ •uaSAxQ •spixQ oiuoqj-BO ■ppv oinoqjB3 •SlUBUIOinTJl •auaiiiqia ■auBqiapi 'naSojpXH CO M o Tj-ino^co vDM N e^ f^O »o idtj-co O'^Oco w -i-oo MMMI-IMI-I Ml- MlHXDMMI-il-IMI-l MMC^ M vo O N M 100 M vO O^ Oco ir>0 ioOMOOOl^i-(t-"u-> O cn^f^O^t-c (N •^•Tt- lOO O Oco 00 CO C^ O VI N ■^ cno O N M a^ O^ O M 00 0^00 O'^'^N cocne^cni-iMioMirjir) MM M M MMUIMMMMMM MC^W M '^r^O N O^Moo vn^^ en cnco CO u^ in rj- cn CO M 00 Tt M N in M •^co CO 00 r^ N N N -^ o o -uj O ^ rt « O O cj >i» cd IJ O ►>.'>. (L) s o • s • c : ^ o : '^ : 6 . o > c