LIBRARY OF THE UNIVERSITY OF CALIFORNIA. Class A SHORT HAND-BOOK HI 'V v ,- : '- of OIL ANALYSIS BY AUGUSTUS H. GILL, S.B., Pn.D. AUTHOR OF ' ' GAS AND FUEL ANALYSIS FOR ENGINEERS, " " ENGINE ROOM CHEMISTRY ' ASSOCIATE PROFESSOR OF TECHNICAL ANALYSIS AT THE MASSACHUSETTS INSTITUTE OF TECHNOLOGY, BOSTON, MASS. FIFTH EDITION REVISED AND ENLARGED OF THE | UNIVERSITY ) OF PHILADELPHIA AND LONDON J. B. LIPPINCOTT COMPANY 1909 ! Copyright, 1897, by J. B. LIPPINCOTT COMPANY. Copyright, 1900, by J. B. LIPPINCOTT COMPANY. Copyright, 1903, by J. B. LIPPINCOTT COMPANY. Copyright, 1905, by J. B. LIPPINCOTT COMPANY. Copyright, 1909, by J. B. LIPPINCOTT COMPANY. Electrotyped and Printed by J. B. Lippincott Company The Washington. Square Press, Philadelphia, U. S. A. v v PREFACE TO THE FIFTH EDITION. , THE changes in the present volume include a description of the new universal viscosimeter, improved methods for the detection of antifluor- escents, and of applying the spontaneous combus- tion test. The portions of the work dealing with the detection of animal and vegetable oils, the treatment of unsaponifiable matter, and the tur- pentines have been entirely rewritten. A new chapter upon waste fats and oils has been added in view of their increasing importance. Other additions are a description of the titer test, another method for sulphur in burning oils, and some new tables. As in the past, minor changes and corrections have been made, thus bringing it is hoped the book well up to present practice. BOSTON, November, 1908. 203801 PREFACE TO THE FIRST EDITION. THIS little book was written primarily to meet the needs of the author's own classes. It is given to the public in the belief that there is a demand for a concise manual for the analysis of oils, which shall give the methods of applying the usual physi- cal and chemical tests to the mineral as well as to the animal and vegetable oils. It is not designed to take the place of any of the existing books, but rather to serve as an introduc- tion to them, more especially to Benedikt-Lewko- witsch, which is to the oil chemist what Fresenius is to the analytical chemist, and to which the writer wishes to express his own indebtedness. The writings of Schaedler, Redwood, Allen, and Brannt have also been freely consulted. Only the more commonly occurring oils are discussed, and these as regards their preparation, properties, analytical constants, the highest, lowest, and average being given, and finally their uses and adulterants. In the use of this book it is assumed that the student is thoroughly familiar with the usual opera- tions of volumetric and gravimetric analysis, and has attained some proficiency in organic chemistry. Acknowledgments are due to Mrs. Ellen H. Richards for hints and suggestions, and to Mr. William L. Root for assistance in reading the proof. BOSTON, November, 1897. 5 CONTENTS. PART I. PHYSICAL AND CHEMICAL TESTS. CHAPTER I. PETROLEUM PRODUCTS. (a) Burning Oils. Flash and Fire Tests Specific Gravity Distillation Test Determination of Sulphur Acidity Sulphuric Acid Test Test for Mineral Salts Water 13 CHAPTER II. PETROLEUM PRODUCTS. (b) Lubricating Oils. Viscosity Specific Gravity Evaporation Cold Flash and Fire Tests Tests for Soap and Antifluorescents Gum- ming Test Friction Tests 26 CHAPTER III. ANIMAL AND VEGETABLE OILS. Specific Gravity Valenta Elaidin Maumene" Test Iodine Number Bromine Number Saponification Value De- tection of Unsaponifiable Oils Special Tests Free Acid and Spontaneous Combustion Tests Drying Test 49 CHAPTER IV. GENERAL CONSIDERATIONS REGARDING LUBRICANTS. Method of Examination of an Unknown Oil.. 86 8 CONTENTS. PART II. DERIVATION, DESCRIPTION, AND EXAMINATION OF CERTAIN OILS. Classification 97 CHAPTER V. PETROLEUM PRODUCTS. Naphthas Gasolenes Kerosenes Lubricating Oils 99 A. OILS AND FATS. GLYCERIDES. CHAPTER VI. VEGETABLE OILS. (1) Drying Oils. Linseed, Raw, Boiled, and Bleached Chinese Wood Poppy- seed Sunflower 103 (2) Semi-Drying Oils. Corn Cotton-seed Sesame Rape-seed Castor 108 (3) Non-Drying Oils. Almond Peanut Olive Rosin Turpentine Blown Oils Palm Cocoanut 113 CHAPTER VII. ANIMAL OILS. (1) Marine Animal Oils. Menhaden Cod Whale 132 (2) Terrestrial Animal Oils. Neat's-foot Horse LardTallow Elaine 134 B. WAXES. LIQUID WAXES. Sperm Oil 139 CHAPTER VIII. WASTE FATS. Wool Fat Distilled Grease Oleines Sod Oil Oil Foots Fullers' Grease Black Oil Garbage Grease 141 APPENDIX. Tables Reagents -Railroad Specifications 153 PRELIMINARY OBSERVATIONS. SAMPLES of oil are almost always handled in the trade, and frequently brought for analysis, in a four-ounce "oil vial." The student will pour out a portion from the quart can, after thorough shak- ing, into such a vial. Before proceeding with the tests to be later described, it is well to make certain preliminary observations upon this sample. The turbidity, showing the presence of water or of oils which imperfectly mix, and the sediment, either stearin or dirt, are to be noted; the color and fluorescence, or "bloom," the latter indicating the presence of mineral oils, are next observed; the color varies from "water white," through straw, lemon-yellow, wine-red, to opaque. The odor and taste may reveal to experts much concerning the source of the oil under examination; for example, the fish oils, especially when warmed, have an unmistakable odor, and the presence of whale oil in sperm is often detected by its "nutty" taste. By inverting the bottle when partially filled, and noting the way in which the oil runs off from the bottom and the number of drops, an approximate idea of the viscosity may be obtained. PART I. PHYSICAL AND CHEMICAL TESTS. OP THE UNIVERSITY OF A SHORT HAND-BOOK OF OIL ANALYSIS. CHAPTER I. PETROLEUM PRODUCTS. (a) Burning Oils. THE tests to be made are, in the order of their importance, flash test, fire test, specific gravity, distillation test, determination of sulphur, acidity, sulphuric acid test, test for mineral salts, deter- mination of water. Flash Test or Point. 1 By flash point we under- stand that temperature to which an oil must be heated to give off vapors which, when mixed with air, produce an explosive mixture. The results of this test will vary according to the quantity of air over the surface of the oil, and whether this be moving or still; also according to the distance of the testing flame from the surface of the oil. Fur- thermore, the size of the flame, the length of its time of action, its form and dimensions, and, lastly, 1 The flash point is oftentimes a valuable means of detecting the admixture of substances; for example, 0.1 per cent, ether in alco- hol may be discovered by this test. See Table II. 13 14 PHYSICAL AND CHEMICAL TESTS. the manner of heating of the oil, will all influence the result. 1 From the above statement and that of Dudley 2 the following points are to be especially noted: 1. The Rate of Heating. The faster the oil is heated the lower will be the flash point, as more vapor is driven out. 2. Size and Depth of Cup. From a large and shallow cup the liquid evaporates faster; hence the lower will be the flash point. The most constant re- sults are obtained from a deep cup about half filled. 3. Quantity of Oil. The larger the amount of oil the more vapor will be driven out; hence the lower will be the flash point. 4. Distance of Testing Flame. The nearer or what amounts to the same thing the larger the testing flame the lower will be the flash point. A large flame may produce local superheating. 5. Point of Application of Testing Flame. The flame should be applied at the edge, as the mixture of air and vapor is more complete; this is best effected by drawing the flame diametrically across the top of the cup. Dr. Dudley cites an instance in which the flash point obtained was considerably too high, owing to the fact that the testing flame was first applied in the centre of the cup. 6. The thermometers used should be frequently compared with a standard instrument. 7. Draughts should be carefully avoided. 1 Engler and Haa.se, Z. anal. Chem., 20, 3 (1881). 'American Engineer and Railroad Journal, 64, 180 (1890). PETROLEUM PRODUCTS. 15 Numbers 1 to 4 may be briefly summarized as follows: any cause producing the rapid evolution of a large amount of petroleum vapor tends to lower the flash point. Barometric changes are, for practical work, negli- gible, each five millimeters between seven hundred and forty-five and seven hundred and seventy-five millimeters causes a variation of but 0.1 C. Lenz 1 states that the initial temperature of the oil is of importance, and as a result of several hun- dred determinations recommends cooling the oil contained in the flashing cup to C. before making the test. In case the oil contains water, it must be removed by treatment with calcium chloride or sulphate. The apparatus in use in this country are divided into two classes, covered testers, in which the cup is covered with a perforated metal or glass plate, and open testers, in which the cup is not so covered. In the author's opinion the covered testers are the more scientific and give the more concordant re- sults, and should be made the standard instruments. Covered Testers. One of the best forms of testing apparatus is that devised by the Michigan State Board of Health in 1873, modified by Dr. A. H. Elliott, and now known as the "New York State Board of Health Tester," shown in Fig. 1. Description. It consists of a copper oil cup, D, holding about ten ounces, the quantity usually 1 Z. anal. Chem., 25, 265 (1886). 16 PHYSICAL AND CHEMICAL TESTS. FIG. 1. contained in lamps, heated in a water-bath by a small Bunsen flame. The cup is provided with a glass cover, C, carrying a thermometer, B, and a hole for the insertion of the testing flame, a small gas flame one-quarter of an inch in length. Manipulation. After describing the apparatus minutely, the regulations of the New York State Board of Health say, 1 " (2) The test shall be applied according to the following directions : "Remove the oil cup and fill the water-bath with cold water up to the mark on the inside. Re- place the oil cup and pour in enough oil to fill it to within one-eighth of an inch of the flange joining the cup and the vapor- chamber above. Care must be taken that the oil does not flow over the flange. Remove all air- bubbles with a piece of dry paper. Place the glass cover on the oil cup, and so adjust the thermometer that its bulb shall be just covered by the oil. "If an alcohol lamp be employed for heating the New York State Board of Health tester. Report of the New York State Board of Health, 1882, p. 495. PETROLEUM PRODUCTS. 17 water-bath, the wick should be carefully trimmed and adjusted to a small flame. A small Bunsen burner may be used in place of the lamp. The rate of heating should be about two degrees per minute, and in no case exceed three degrees. "As a flash torch, a small gas jet one-quarter of an inch in length should be employed. When gas is not at hand employ a piece of waxed linen twine. The flame in this case, however, should be small. "When the temperature of the oil has reached 85 F. the testings should commence. To this end insert the torch into the opening in the cover, passing it in at such an angle as to well clear the cover, and to a distance about half-way between the oil and the cover. The motion should be steady and uniform, rapid and without any pause. This should be repeated at every two degrees' rise of the thermometer until the thermometer has reached 95, when the lamp should be removed and the testings should be made for each degree of temper- ature until 100 is reached. After this the lamp may be replaced if necessary and the testings con- tinued for each two degrees. "The appearance of a slight bluish flame shows that the flashing point has been reached. "In every case note the temperature of the oil before introducing the torch. The flame of the torch must not come in contact with the oil. "The water-bath should be filled with cold water for each separate test, and the oil from a previous test carefully wiped from the oil cup." 2 18 PHYSICAL AND CHEMICAL TESTS. FIG. 2. Open Testers. The Massachusetts statute is by no means as definite as that of New York; the courts have decided that custom fixes the method of testing. The law says/ "No person shall offer for sale. . . illuminating oils made from coal or petroleum which will evaporate a gas under 100 F. [that is, the flashing point is 100 F. A. H. G.], or ignite at a temper- ature of less than 110 F., to be ascertained by the application of Tagliabue's or some other approved instrument. " Manipulation. Tagliabue's open tester (Fig. 2) is the official instru- ment. This is similar to the pre- ceding, except that it is smaller, has a glass oil cup and no cover. The water-bath is filled as before, and the oil cup to within three- thirty-seconds of an inch of the top. The heating flame is adjusted so that it is three-fourths of an inch high, and the heating pro- ceeded with at the rate of two and a half degrees per minute, until 97 F. is reached, when the test flame is applied and the testings made every three degrees until the flash point is reached. The whole time of making the test should be half an hour. Tagliabue's open tester. Revised Statutes of Massachusetts, 1902. PETROLEUM PRODUCTS. 19 Fire Test. The fire test of an oil is the temper- ature at which it will give off vapors which when ignited will burn continuously. It is made by con- tinuing to heat the oil (the cover being removed in the case of a closed tester without slipping out the thermometer) at the same rate after the flash test is made and noting the point as indicated above. The flame is extinguished by a piece of asbestos board and the heating discontinued. In the case of many illuminating oils this point is from 10 to 20 F. higher than the flash point. Notes.- In the case of "Mineral Sperm" (300 F. fire test petroleum) these tests should be made with the instrument for lubricating oils (page 41). The heating should be at the rate of 15 F. per minute, and the testing flame first applied at 230 F., and then every seven degrees until the flashing point is reached. The most satisfactory way of making these tests is to place the watch upon the desk and read the thermometer at the expiration of every minute, not- ing each reading down in the proper column in the laboratory note-book. Specific Gravity. This is usually effected by the hydrometer; a hydrometer jar is four-fifths filled with the oil, a Baum6 hydrometer introduced into it, and the depth read off to which the instru- ment sinks in the oil. This may be effected by placing a strip of white paper back of the jar and noting the point at which the lower meniscus of the oil touches the scale. The temperature of the 20 PHYSICAL AND CHEMICAL TESTS. oil is taken at the same time, and in case it be not 60 F. (15.5 C.), for every increase of 10 F. (5.5 C.) subtract 1 Baume from the hydrometer read- ing. The specific gravity may be found by the formula rl~m*> B representing the reading Baume at 15.5 C. Notes. Inaccurate graduation may cause an error of 0.001, but if the instrument be carefully calibrated it is accurate to 0.0002. 1 The student will make this test upon the oil at the ordinary temperature and correct the gravity for tempera- ture as given above. In practice this can be done by Tagliabue's "Manual for Inspectors of Coal Oil," which gives the readings at 60 F. for any gravity from 20 to 100 Baume, between 20 F. and 109 F. Distillation Test. As a means of evaluating samples of kerosene, Beilstein 2 recommends the fractional distillation of two hundred cubic centi- meters, using a tower. As the method of Engler is more frequently employed, that will be described. He uses a peculiar boiling flask, six and five-tenths centimeters in diameter, with neck fifteen centi- meters long, and with the side tube about nine centimeters from the springing of the bulb; this is connected with a Liebig condenser and heated by a small lamp with a shield. Manipulation. One hundred cubic centimeters of the oil are measured into the boiling flask and 1 Wright, J. Soc. Chem. Ind., 1 1, 302 (1892). 3 Z. anal. Chem., 22, 309 (1883). PETROLEUM PRODUCTS. 21 distilled at the rate of two to two and five-tenths cubic, centimeters per minute, the distillate being caught in a 25 cc. burette or graduate. When the distillation is to be broken, the lamp should be taken away and the temperature allowed to sink twenty degrees and again brought to the breaking or frac- tionating point, as long as any considerable quantity goes over. The distillation is first broken at 150 C., and then each fifty degrees until 290 C. is reached; in this way a much better idea of the value of the oil is obtained than if the distillation were allowed to proceed continuously between these points. The lighter portions, for example, those between 150 and 200, burn much better than those between 250 and 290; the heavy portions of American petroleum burn much better than those of the Russian oils. The averages from four samples of Caucasian and ten samples of American oils subjected to this test were as follows, in per cent, by volume: 1 Below Above 150 C. 150-290C. 290 C. Caucasian petroleum 8.0 86.6 5.4 American petroleum 16.9 57.1 26.0 Determination of Sulphur. In addition to the preceding tests, Professor Peckham 2 considers the determination of sulphur to be of considerable im- portance. The deleterious effect of the oxides of sulphur upon hangings and bindings is well known, sulphuric acid being their ultimate product. The 1 Veith, " Das Erdoel," p. 244. 2 Report upon Petroleum. 22 PHYSICAL AND CHEMICAL TESTS. sulphur exists in combination, partly as compounds formed from the sulphuric acid used in refining 1 and partly as sulphides already formed in the oil. -Its qualitative detection may be effected by heating the oil to its boiling point with a bright piece of sodium or potassium. If sulphur compounds be present, a yellowish layer is formed upon the metal. After cooling add distilled water drop by drop until the metal is dissolved, and test for sulphides with sodium nitro-prusside. For the quantitative determination of sulphur many methods have been proposed. Engler 2 and Kissling 3 burn the oil in an apparatus similar to that used for the determination of sulphur in illumi- nating gas. This can be easily made from a small test-tube three-eighths of an inch in diameter and two and three-eighths inches long, fitted with a stopper carrying a narrow piece of tubing through which passes a piece of lamp-wicking the whole serving as a small lamp. This is burned under a funnel with the stem bent to connect with two wash-bottles containing bromine water and the products of the combustion of the oil sucked through these. The lamp is partly filled with the oil to be tested and weighed, burned until about a gram of oil has been consumed and again weighed. The sulphuric acid formed in the bottles containing bromine water l, Dingier 's pol. J., 216, 47 (1875). 2 Chem. Ztg., 20, 197; abstr. J. Soc. Chem. Ind., 15, 383 (1896). 8 Ibid., 199; abstr. Analyst, 21, 162 (1896). PETROLEUM PRODUCTS. 23 is determined in the usual way with barium chloride. The determination should of course be made in an atmosphere free from sulphur. Aufrecht 1 distils the oil with sodium bicarbonate, which takes up* the sulphur. Mabery 2 states that for oils containing more than 0.01 per cent, of sulphur the well-known method of Carius the oxidation in a sealed tube with fuming nitric acid leaves little to be desired. For oils containing a smaller percentage than this he employs a modification of Sauer's method the combustion of the oil in a stream of air and subsequent ab- sorption of the products in standard sodium hydrate. The percentage of sulphur should not exceed 0.05; Engler, loc. cit., and Kissling 3 found 0.02 to 0.03 in the Pennsylvania, and 0.04 to 0.05 in the Lima kerosenes. Detection of Acidity. Shake equal quantities of oil and warm water in a test-tube, pour off the oil, and test the water with litmus paper. If the water be strongly acid, the quantity may be deter- mined as in "Free Acid," page 78. The acid in this case is most probably sulphuric, coming from the refining process. Sulphuric Acid Test. The object of this test is to judge of the degree of refinement of the oil, a perfectly refined oil giving little or no color when submitted to the process. One hundred grams 1 Pharm. Ztg.,41, 469; abstr. J. Soc. Chem.Ind., 15, 680 (1896). 2 Am. Chem. J., 16, 544 (1894). 3 Ch. Rev. d. F. & H. Ind., 14, 157 (1906), Anal., 31, 342. 24 PHYSICAL AND CHEMICAL TESTS. of oil and forty grams of sulphuric acid, 1.73 spe- cific gravity, are shaken together for two minutes in a glass-stoppered bottle and the color of the acid noticed. In accurate work this color is matched by solutions of Bismarck brown. 1 Mineral Salts. Salts of calcium or magnesium when dissolved in the oil diminish its illuminating power; their action is to form a crust on the wick and prevent access of air. Redwood 2 states that 0.02 gram of either of these salts in one thousand grams of oil diminishes the illuminating power thirty to forty per cent, in eight hours. They are determined by distilling one hundred or two hundred cubic centimeters of the oil down to about twenty cubic centimeters, evaporating and igniting this residue, and subsequently treating with hydrochloric acid. The calcium and mag- nesium are then determined in the usual way. Determination of Water. 3 By rubbing the oil together with a little eosin on a glass plate the oil will take on a pink color if water be present. Allen 4 states that water in oils may be determined by the addition of a weighed amount of gently ignited plaster of Paris. This is washed with a little gaso- lene, dried at a gentle heat, and reweighed, the gain in weight being the water present. 1 J. Soc. Chem. Ind., 15, 678 (1896). * Dingier pol. J., 255, 427 (1887). 3 See, also, Davis, J. Am. Chem. Soc., 23, 487 (1901). * Commercial Organic Analysis, ii. 491. PETROLEUM PRODUCTS. 25 Another method of determination consists in distilling off the water in a suitable apparatus and measuring it after the method of Dean for the determination of moisture in creosoted wood. 1 It is to be noted that one per cent, of water in an oil extinguishes the flame when making the flash test: three or four per cent, are apparently without influence on the viscosity. 2 REFERENCES. In addition to the literature previously given, the student is referred to the following: ELLIOTT, A. H., New York State Board of Health Report, 1882, pp. 449-496. This gives comparative tests of the various testers and a resume of bibliography and patents up to that year. PECKHAM, S. F., " Report on the Production, Technology, and Uses of Petroleum and its Products," U. S. Census Report, 1885. THORNER, W., Chemiker Ztg., 10, 528, 553, 573, 582, 601; ab- stracted in J. Soc. Chem. Ind., 5, 371 (1886). " Petroleum as an Illuminating Agent." NEWBURY and CUTTER, Am. Chem. J., 10, 356 (1888). "On the Safety of Commercial Kerosene Oil." AISINMAN, Chem. technische Vortrage, ii. 325. German methods of testing. 1 Circular 134 (1908), U. S. Dept. Agriculture. 2 Charitschkow, Chem. Ztg., 31, 376 (1908). CHAPTER II. PETROLEUM PRODUCTS. (b) Lubricating Oils. THE tests to be made are, in the order of their importance, viscosity, specific gravity^ evapora- tion, cold test, flash test, fire test, test for soap, test for antifluorescents, friction test. The office of a lubricant is to prevent the attri- tion of axle and journal by interposing itself be- tween them in a thin layer, upon which the shaft revolves. The ideal lubricant is that which has the greatest adhesion to surfaces and the least cohe- sion among its own particles, or, as the practical man expresses it, the most fluid oil that will do the work and stay in place. The determination of its viscosity or "body" is then of the first importance. Viscosity is the degree of fluidity of an oil or its internal friction. It is independent of the specific gravity of the oil, although this in the pipette instruments influences the time of efflux. Within certain limits it may be taken as a measure of the value of oil as a lubricant, by comparing the vis- cosity of the oil under examination with that of other oils which have been found to yield good results in practice. The instruments employed for its determination may be divided into two classes, pipette viscosim- 26 LEUM PRODUCTS. 27 eters, giving the time of efflux, as those of Saybolt, Engler, and others, and torsion viscosimeters, giving the retardation due to the oil, those of Napier and Doolittle. Of these but two, the Saybolt and Doolittle, will be minutely described. The Saybolt Viscosimeter. 1 This is made in four forms, A, B, C, and the Universal. Apparatus "A" is the standard for testing at 70 F. Atlantic Red, Paraffine, and other distilled oils; "B" for testing at 70 F. Black Oils of 0, 15, 25, and 30, Cold Test, and other reduced oils up to, but not including, Summer Cold Test Oil. Apparatus "C" is used for testing at 212 F. Reduced, Summer, Cylinder, Filtered Cylinder, XXX Valve, 26.5 Be., and other heavy oils. The Standard Universal Viscosimeter is used for testing Cylinder, Valve, and similar oils at 210 F.; Reduced Black Oils at 130F.; Spindle, Paraffine, Red, and other distilled oils at 100 F. Apparatus "A." Description. The "A" appa- ratus (Fig. 3) consists of a brass tube, T, containing about sixty-six cubic centimeters, and about three centimeters in diameter and eight centimeters long, forming the body of the pipette. It is connected at the bottom with a smaller tube, t, having a win- dow, w. This pipette is screwed into the piece p carrying the jet, 1.75 millimeters in diameter; the lower part of this piece is expanded at the 1 Redwood, J. Soc. Chem. Ind., 5, 124 (1886). 28 PHYSICAL AND CHEMICAL TESTS. FIG. 3. bottom to admit of the insertion of a cork. The upper part of the pipette is perforated with a number of small holes leading to a gallery, G, five centimeters in diameter and one and three-tenths centimeters deep. This enables a workman to fill the apparatus to the same point every time. This pipette is held by p in a tank of water eighteen cen- timeters high and twenty centimeters in diameter, also provided with win- dows to observe the efflux of the oil. A tin cup with spout, thermometer, pipette with rubber bulb, stop-watch, and beaker for waste oil, complete the outfit. Manipulation. H a v i n g the bath of water prepared at 70 and the oil in the tin cup about 69.5, clean the tube out with some of the oil to be tested by using the plunger sent with the instrument. Place the cork air-tight in the lower outlet tube and pour the oil into the tube proper until it flows into the overflow cup. By stirring with the thermometer bring the oil to exactly 70, remove the thermometer, and draw with a pipette the surplus oil in the overflow cup down below the overflow holes. The temperature Saybolt's "A" viscosimeter. PETROLEUM PRODUCTS. 29 still remaining constant, with the watch in the left hand, draw the cork with the right and simul- taneously start the watch. Towards the end of the run, watch the peep-hole closely through the window in the bath, and at the first appearance of space not filled with oil in the glass outlet tube stop the watch. Apparatus " C." Standard for testing at 212 F. Description. This is very similar to the preceding apparatus. The top is closed around the oil gallery, the windows omitted, and a steam connection pro- vided. The quantity of oil is determined by allowing it to run into a sixty cubic centimeter graduated flask. The size of the jet is three-sixty-fourths of an inch. 1 Manipulation. Fill the bath with water and attach steam inlet to bottom cock. The upper outlet is for exhaust and overflow. With the water boiling and the bath thermometer registering 212, and the oil to be tested having been put through the strainer into one of the tin cups, pour some of the oil into the tube and clean out with the plunger sent with the instrument; never use other than the plunger in cleaning. Place the cork air-tight in the lower outlet tube, and pour the oil into the tube until it overflows into the overflow cup. Allow the oil to heat until the temperature is 210, stirring the oil with the ther- mometer during the heating. Having the bath at ^tillman, J. Anal, and App. Chem., 5, 322 (1891). 30 PHYSICAL AND CHEMICAL TESTS. 212 and the oil not below 210, remove the ther- mometer. Draw the surplus oil from the overflow cup with a pipette down to and below the overflow holes; this insures a positive starting-point. Place the sixty cubic centimeter flask under and directly in a line with the outlet jet, and as close to the jet as it is practicable, to permit of room for drawing the cork. With the watch in the left hand, draw the cork with the right and simultaneously start the watch. The time required for the delivery of sixty cubic centimeters is the viscosity. The tube should be cleaned out before each test with some of the oil to be tested. Notes. Instead of timing the oil as given in the directions above, the writer has found it better to start the watch, and the instant the second-hand crosses the sixty seconds mark twist out the cork with the right hand. The tube should be cleaned out before each test with some of the oil to be tested, using the plunger P for this purpose. Black oils or any oil contain- ing sediment should be carefully strained before testing or " running, " as it is technically termed. The instruments should be carefully guarded from dust when not in use. The Universal Viscosimeter. Description. This is similar to Apparatus C, just described: in addition to the steam connection it is provided with a ring burner for heating by gas. Sixty cubic centimeters of oil are run through it as with the preceding instrument. PETROLEUM PRODUCTS. 31 It may be used for testing Cylinder, Valve, and similar oils with bath at 212 and oil at 210; for testing Reduced, Black Oils, bath and oil at 130; for testing Spindle, Paraffine, Red, and other dis- tilled oils, batl^ and oil at 100. When used for testing at 212 F., it may be used with either gas or steam alone or both in combination. If with both, the steam may be introduced slowly, more for its condensation to replace evaporation than for real heating purposes, depending upon the gas flame to reach the boiling point, and keeping it there during the operation of test. The bath vessel should always be kept full during a test, whether at 212, 130, or 100. When used at 130 or 100, gas alone is used to bring the bath to the prescribed temperature, and turned off during the operation of test, the large size of the bath usually permitting making one test without reheating. Manipulation. 1. Have the bath of water prepared at the pre- scribed temperature. 2. Have the oil strained into one of the tin cups, in which cup it may be heated up to about the standard temperature. 3. Clean out the tube with some of the oil to be tested by using the plunger sent with the in- strument. 4. Place the cork (as little distance as possible) into the lower outlet coupling tube just enough to make air-tight, but not far enough to nearly touch 32 PHYSICAL AND CHEMICAL TESTS. the small outlet jet of the tube proper (one-eighth to one-quarter of an inch may be enough.) 5. Pour the oil from the tin cup (again through the strainer) into the tube proper until it overflows into the overflow cup up to and above the upper edge of tube proper. 6. Now again see that the bath is at the pre- scribed temperature. 7. Use the thermometer sent with the instrument by stirring to bring the oil just to the standard temperature. 8. Remove the thermometer. 9. Draw from the overflow cup, with a pipette, all the surplus oil down to and below the upper edge of tube proper. This insures a positive start- ing head. 10. Place the 60 cc. flask under and directly in line with the outlet jet, and as close to the coup- ling tube as is practical to permit of room for drawing the cork. 11. With the watch in left hand draw the cork with the right, and simultaneously start the watch. 12. The time required in the delivery of 60 cc. is the viscosity. 13. Clean out the tube proper before each test with some of the oil to be tested. 14. No drill or other instrument should ever be used in the small outlet jet of tube proper. The results obtained with this instrument are not the same in many cases as those furnished by the A, B, and C instruments, nor do they seem PETROLEUM PRODUCTS. 33 FIG. 4. to have been adopted by the trade generally. Tables V-VIII of the appendix will give a means of comparing the results obtained with the Saybolt, Doolittle, and Engler Viscosimeters. It is worth noting that three or four per cent, of water are apparently without influence on the viscosity. Doolittle's Torsion Viscosimeter. 1 Description. The apparatus con- sists of a cylinder (Fig. 4) rotating in the oil, and a graduated disk, Z>, to measure the amplitude of rota- tion. These are supported by a fine piano wire from the substantial stand S, provided with levelling screws; a lens, Z, enables the gradu- ations on the disk to be read more accurately, and a bath, J5, filled with water or oil serves to maintain any desired temperature. The instru- ment should be so adjusted that it will read within one-half degree of the zero point on either side of it when vibrating through an arc of one hundred and eighty degrees; this can be effected by loosening the set screw at the top and turning the pin which holds the wire. Manipulation. Immerse the friction cylinder in the oil by slipping its stem into the stem of the disk, and adjust the temperature very carefully to Doolittle's torsion viscosimeter. Doolittle, J. Am. Chem. Soc., 15, 173, 454 (1893). 34 PHYSICAL AND CHEMICAL TESTS. the point at which it is desired to determine the viscosity; great care must be taken to keep this temperature constant during the test. Either a water-bath or bath of lard oil according to the temperature desired may be used. The oil in the cup should cover the cylinder with a layer three -sixteenths of an inch deep when it is swinging freely, and it should be in the centre of the cup. By lifting the milled head at the top of the in- strument out of the notch, and turning it completely around from right to left until it drops into the notch again, the wire is rotated three hundred and sixty degrees. By raising the disk by means of the cam the friction cylinder will rotate in the oil by virtue of the torsion of the wire. The disk will rotate three hundred and sixty degrees and a por- tion of another arc, which latter is the first reading, the end of the first swing = 355.6 right. The left-hand swing is ignored, and the arc on the next swing to the right = 338.2 right, is read. The retardation produced by the oil is 355.6 338.2 = 17.4. The vibrations should now be stopped, and the head should be turned in the opposite direction and the readings to the left taken, and the average of the two considered as the retarda- tion of the oil. The results are expressed in the number of grams of sugar contained in one hundred cubic centimeters of sugar syrup at 60 F., its viscosity being taken at a temperature of 80 F. In the ex- PETROLEUM PRODUCTS. 35 ample cited, 17.4 (with the small cylinder) repre- sents a viscosity of 65.6; this means that if 65.6 grams of granulated sugar were dissolved in water at 60 F., made up to one hundred cubic centimeters and then heated to 80 F., its vis- cosity would be the same as that of the oil under examination. The readings of the first and second swings are to be taken, as later vibrations give different results. The wire and cylinder should be handled with great care, as they are very sensitive to abuse. The wire should be greased with tallow occasion- ally, and in case of a new instrument, restandard- ized after six months' use. In case a new wire is inserted the instrument must be recalibrated. When not in use the point should be kept under the index, the disk upon its supports, and the wire without torsion. Traube's Viscosimeter. Dr. T. Traube, 1 of Han- over, uses a pipette viscosimeter consisting of a vertical bulb with a long horizontal capillary jet, it being contained in a trough to keep the tempera- ture constant. About eight cubic centimeters of oil are used for a test, and forced through the jet under a pressure of sixty centimeters of water. This jet is thirty centimeters long and of various diameters, there being three pipettes with jets 1.5, 0.8, and 0.5 millimeters in diameter, according to the kind of oil to be tested. Traube, Z. Ver. deutsch. Ing., 31, 251; abstr. J. Soc. Chem. Ind., 6, 414 (1887). 36 PHYSICAL AND CHEMICAL TESTS. Wright 1 states that the results correspond more closely to those obtained on a friction machine than those of any other instrument, a statement which the author's experiments would seem to confirm. The instrument certainly is more sensi- tive than any with which the author is acquainted. Specific Gravity. 1. By the Hydrometer. See page 19. 2. By the Westphal Balance. This is a specially constructed instrument with a glass plummet carrying a thermometer counterbalanced by a weight. Upon immersing the plummet in a liquid the positions of weights, which must be added to restore the equilibrium, represent the specific grav- ity directly. The largest weight represents the first decimal place, the next the second, and so on. The instrument is placed upon a level table, and by means of the levelling screw is brought into ad- justment, i.e., so that the point upon the beam is exactly opposite the point upon the fixed part. The plummet is now placed in the vial or balance jar containing the oil, cooled to 15.5 C., hung upon the balance, being careful to completely immerse it in the oil, weights added to restore the equilibrium, and the specific gravity read off as above described. Notes. In using the instrument care should be taken to place the riders at right angles to the 1 Oils, Fats, and Waxes, p. 109. For the absolute viscosimeter, see "Lubrication and Lubri- cants, " Archbutt and Deeley, pp. 132-143. PETROLEUM PRODUCTS. 37 beam, otherwise an error of 0.0005 may be intro- duced; furthermore, the loop upon the knife-edge should always be in the same position. In buying an instrument the spaces upon the beam should be tested with dividers to insure their equality, other- wise serious errors may be caused. 1 The limit of accuracy is about 0.0005. 2 Care should also be taken that the plummet does not touch the sides of the jar or vial. For solid fats and some oils the specific gravity is taken at 100 C., using a special plummet. McGill 3 states that the balance is more sensitive for viscous oils when the specific gravity of the plummet is 4.0 than when it is 2.0. Evaporation Test. 4 The object of this test is to determine what percentage of an oil more espe- cially a spindle oil is volatile when exposed to nearly the same conditions as it is on a bearing. The oil is exposed upon annular disks of filter- paper one and five-eighths inches outside diameter, with hole five-eighths of an inch in diameter, which have been standing in a sulphuric acid desiccator for several days, contained in a flat watch-glass. Manipulation. The watch-glass and paper are weighed, to tenths of a milligram, and about 0.2 gram of oil brought upon it- by dropping from 1 Allen, Analyst, 14, 11; Stock, ibid., 50 (1889). 2 Richmond, ibid., 65. 3 Analyst, 21, 156 (1896). 4 See, also, Archbutt, J. Soc. Chem. Ind., 15, 326 (1896). 38 PHYSICAL AND CHEMICAL TESTS. a rod, and accurately weighed. The watch-glass is now placed in an air-bath, the temperature of which remains nearly constant at 60 to 65 C. (140 to 150 F.), and heated for eight hours. It is then cooled and reweighed, the loss being figured in per cent. No oil should be passed which gives an evaporation of more than four per cent. The following table of results upon some spindle oils shows the relation of gravity, flash point, and evaporation: Gravity. Flash, F. Evaporation. 298 7.0 per cent. .846 318 4.4 348 2.0 .852 348 1.0 .856 336 1.4 .862 352 0.9 .866 366 1.7 .870 384 0.8 .882 364 1.7 Notes. The temperature employed, 65 C., is approximately that attained by a bearing (in a spin- ning frame) after running two hours, thus leaving the oil exposed to it for eight hours, assuming a ten- hour day. The test is important to the insurance under- writer, because it measures the amount of inflam- mable material sent into the air, and hence the liability to cause or aid conflagrations; it is impor- tant to the mill-owner, as it indicates the quantity of oil left upon the bearing, hence serving its purpose. Cold Test. This may be defined as the tempera- ture at which the oil will just flow. PETROLEUM PRODUCTS. 39 Manipulation. A four-ounce vial is one-fourth filled with the oil to be examined, a short, rather heavy, thermometer inserted in it, and the whole placed in a freezing mixture. When the oil has be* come solid throughout, let it stand one hour; the vial is removed, the oil allowed to soften, and thoroughly stirred until it will run from one end of the bottle to the other. The reading of the thermometer is now taken by withdrawing it and wiping off the oil with waste to render the mercury visible. 1 The chilling point is the temperature at which flakes or scales begin to form in the liquid, and is determined similarly, by cooling the liquid five degrees at a time. Freezing Mixtures. For temperatures above 35 F. use cracked ice and water; between 35 and F. use two parts of ice and one part of salt; and from to 30 F. use three parts of crystal- lized calcium chloride and two parts of fine ice or snow. A still more convenient means is by the use of solid carbonic acid dissolved in ether, giving 50 F. readily. The preceding method is open to quite an error from the personal equation of each observer. To obviate this Martens 2 proceeds as follows: The oil is poured into a U-tube one centimeter in diameter, sixteen centimeters high, with three centimeters between the bends, to a depth of three 1 Dudley and Pease, Am. Eng. and R. R. J., 69, 332 (1895). 2 Mitt. kgl. tech. Versuchstation; abstr. J. Soc. Chem. Ind., 9, 772 (1890). 40 PHYSICAL AND CHEMICAL TESTS. centimeters; it is then placed in a freezing mix- ture, cooled, and connected with a blast at a con- stant pressure of three centimeters. The temper- ature at which the oil begins to flow under these conditions is considered as the cold test. Flash Point. Several forms of apparatus for testing the flash point of lubricating oils have been devised: Pensky-Martens's closed tester employing a stirrer is used in Germany. Martens states in a later article that stirring is unnecessary. In this country an open cast-iron or spun brass cup If inches high by 2J inches in diameter heated by a Tirrill burner in an air-bath is quite extensively used. Dudley and Pease use an open porcelain dish heated with a Bunsen burner. Description. The apparatus in use in the author's laboratory is similar to the New York State tester, and consists of a covered copper cup shown at about one-tenth the size in Fig. 5 supported by iron wire gauze upon an iron stand and heated by a Tirrill burner. Manipulation. The cup is filled with oil to within three-eighths of an inch of the flange (in case of cylinder or oils flashing above 500 one- half inch), all air-bubbles removed, the flange and top of cup carefully wiped free of oil, the cover put on, and the thermometer inserted so that its bulb is half-way between the surface of the oil and bottom of the cup. The lamp is placed under- neath, carrying a flame about an inch in height, the bottom of the cup being two and a half inches PETROLEUM PRODUCTS. 41 from the mouth of the burner, and the heating commenced. The rate of heating should be 15 F. per minute, and may be readily regulated by the burner used. The testing flame should be first applied at 250 F., and then every half-minute FIG. 5. Flash apparatus. until the flash point is reached. This is indicated by a slight puff of flame out of the testing hole. Fire Test. The cover is supported above the cup, and the heating and application of the testing flame continued as in making the flash test. The method of recording is the same as in the case of the illuminating oils, one column for times 42 PHYSICAL AND CHEMICAL TESTS. and another for temperatures; the student is recommended to read again pages 13-19. Holde 1 finds that with oils flashing between 172 C. and 241 C. the exact quantity of oil used is of little importance. In these particular cases a difference of filling of thirteen cubic centimeters altered the flash point only 1-1.5 C. For the effect of water see p. 25. It is worthy of notice that the free acid contained in an oil lowers its flash point apparently in pro- portion to the quantity present. Detection of Soap. To increase the viscosity of an oil, 2 resort is had to the use of "oil pulp/' " oil-thickener/ 7 or " white gelatin/' usually an oleate of aluminium, though other bases may be present. Its disadvantages are that it causes the oil to chill more easily and to emulsify, thus increas- ing the friction. Furthermore, it is precipitated by contact with water or steam, causing clogging of the machinery. The test depends upon the fact that the meta- phosphates of the earthy and alkali metals and aluminium are insoluble in absolute alcohol. 3 The test is applied as follows: Five to ten cubic centimeters of the oil to be tested are dissolved in about five cubic centimeters of 86 gasolene or ether, and about fifteen drops of the phosphoric 1 J. Soc. Chem. Ind., 16, 322 (1897). 2 In a case which came to the writer's notice the oil would not flow out of the Saybolt "A" apparatus at 70, at 85 required 1167", and at 110, 181". 3 Schweitzer and Lungwitz, J. Soc. Chem. Ind., 13, 1178 (1894). PETROLEUM PRODUCTS. 43 acid solution (Appendix, Reagents) added, shaken and allowed to stand; the formation of a flocculent precipitate indicates the presence of soap. An idea of the kind of soap can be often gained by adding an alcoholic solution of PtCl 4 . If the pre- cipitate becomes crystalline it is a potash soap; if it dissolves, soda, lime, or magnesia; if unchanged, alumina or iron. For the accurate determination of these com- pounds a known weight of the oil must be ignited, the residue determined and quantitatively examined. Caoutchouc. Holde 1 states that one to two per cent, of unvulcanized caoutchouc is sometimes added to oils to increase their viscosity. This may be detected by adding three parts of alcohol to four parts of the ethereal solution, whereby the rubber material is precipitated and may be dried and weighed. Tests for Antif luorescents. 2 It is often desired to remove the fluorescence or " bloom" from petroleum oils. This may be effected by refining with chromic acid, or more easily by the addition of a small quantity of nitro-naphthalene or nitro-benzene. The latter may often be detected by the odor. The test is made by boiling about one cubic centimeter of the oil with three cubic centimeters of ten per cent, alcoholic potash for one to two min- utes. If either of the nitro compounds be present, a blood- or violet-red coloration is produced: a 1 " Untersuchung d. SchmierSle," p. 183. 2 Holde, J. Soc. Chem. Ind., 13, 906 (1893). 44 PHYSICAL AND CHEMICAL TESTS. pure mineral oil is changed only to yellow or brown- ish-yellow by this treatment. In case the char- acteristic color does not appear the following test may be applied. 1 It depends upon the reduction of the nitro bodies to their amines. A few cubic centimeters of the oil are heated with feathered tin and hydrochloric acid in an Erlenmeyer flask for ten minutes: this can be aided by the introduction of a piece of platinum wire. The oil is separated by a separatory funnel and filtration through a wet filter, the filtrate treated in another separatory with sodium hydrate until the tin hydrate redissolves and shaken out with 10-20 cc. of ether. The amines go into solution in the ether, giving to it a violet color and fluorescence in the case of a-napthylamine. These can be recognized by their odor, that of napthylamine being very characteristic. The latter may be recognized by dissolving in hydrochloric acid, evaporating the latter, and upon treatment with ferric chloride obtaining an azure-blue precipi- tate. This changes when filtered off to purple-red and the filtrate to violet. Aniline can be recognized by solution in con- centrated sulphuric acid and the red and then blue color which appears on the addition of a small crystal of potassium bichromate. Free aniline is also temporarily colored violet by a solution of bleaching powder. 1 Holde, "Untersuchung, u. s. w." p. 186. PETROLEUM PRODUCTS. 45 To ascertain if an oil be fluorescent, place a few drops upon a piece of hard rubber or other black surface and observe if any trace of blue color be perceptible. Test for Fatty Oils. To detect small quantities of fatty oil (one-quarter to two per cent.) Lux 1 recommends heating a few cubic centimeters of the oil for fifteen minutes with some bits of sodium in a test-tube in an oil-bath; a similar test is made with sodium hydrate. The temperature employed should be for light oils about 230, for dark oils 250 . 2 In case fatty oil be present, the contents of one or both of the tubes solidify to a jelly of greater or less consistence according to the amount of fatty oil present. The quantitative determination of these oils, as for example in cylinder oils, is effected after the manner of determining the saponification value (p. 65) or the detection of unsaponifiable oils in fatty oils (p. 68). Schreiber 3 adopts a similar method to Sweetham and Henriques, in that he dissolves 5 grams of the oil in 25 cc. of benzole, adds 25-50 cc. alcoholic potash, and boils for half an hour on the water- bath, using a three-foot glass tube as a condenser. Gumming Test. 4 This is designed to give an idea of the amount of change that may be expected 1 Z. anal. Chem., 24, 357 (1885). 2 Holde, Untersuchung d. Schmierole u. Fette, p. 175. 3 J. Am. Chem. Soc., 29, 74 (1907). 4 Gill, J. Am. Chem. Soc., 24, 467 (1902). 46 PHYSICAL AND CHEMICAL TESTS. in a mineral oil when in use. These resinified products increase the friction of the revolving or rubbing surfaces. 1 It is also a measure of the amount that an oil will " carbonize" in a gas or gasolene engine cylinder. It is applied after the manner of the Elaidin Test, by thoroughly mixing together five grams of the oil in a cordial glass with eleven grams of nitrosulphuric acid and cool- ing by immersion in a pan of water at 10-15. Brownish spots or, in case of a bad oil, masses, form around the edges and become red in the course of two hours. The cordial glass is filled successively three times with 70-86 naphtha and the oil dissolved off the surface of the acid, the gasolene solution being sucked off into a bottle with an air-pump. Care is taken not to suck off any of the tarry matter formed. The acid can be neutralized with ammonia and the tar can be collected on a tared filter, washed with gasolene that leaves no residue on evaporation, dried at a low temperature, and weighed as gummy matter. As shown by long practical experience, the oil showing the least tar or gum is the best oil; it also absorbs the least oxygen. Friction Tests. The writer is inclined to doubt if friction tests are worth the outlay for a machine and the time expended in their execution. With- out question they do determine the relative efficiency as regards lubricating power of different oils, but 1 Aisinman, J. Soc. Chem. Ind., 14, 282 (1895). PETROLEUM PRODUCTS. 47 the conditions under which the test is made seldom occur in practice; the bearings upon which the oil is tested are as nearly perfect as can be made, and the feed and load are as regular as is possible; in other words, the conditions are ideal. The lubricating power of an oil is so closely related to its viscosity 1 that the author believes that results of more practical value can be obtained by the determination of the viscosity of the oils, and subsequent observation of their behavior in actual use, than by the longer and more trouble- some friction test. In case, however, it be desired to make the friction test, the following machines, it is believed, will be found to be most satisfactory for the purpose. For spindle oils and light lubricating oils, the Ordway-Woodbury machine, 2 described in the "Proceedings of the American Society of Mechan- ical Engineers/' 1880, 74, and 1884, 136; also in Brannt, " Petroleum and its Products," p. 480. For heavy oils and railroad work, the large machine of Thurston, 2 described in his "Friction and Lost Work in Machinery and Millwork, " p. 254; also in Brannt, p. 486; also in Archbutt and Deeley. 3 Or use may be made of the Richie* machine made by the Riehle Bros, of Philadelphia. 4 1 Brannt, " Petroleum and its Products," p. 510; Woodbury, vide infra. 2 Made by the Pratt & Whitney Co., Hartford, Conn. 3 "Lubrication and Lubricants," 1907, pp. 332-348. 4 Ibid., p. 359. 48 PHYSICAL AND CHEMICAL TESTS. For machines using a flooded bearing the Beau- champ-Tower machine, described in the "Proceed- ings of the Institution of Mechanical Engineers of Great Britain/' 1883, 632; 1884, 29; 1885, 58; 1888, 173; 1891, 131; also in Archbutt and Deeley. 1 1 Ibid., p. 355. CHAPTER III. ANIMAL AND VEGETABLE OILS. THE tests most commonly employed for the identification of these oils are as follows: specific gravity, Valenta test, elaidin test, Maumene test, heat of bromination test, iodine number, and saponification value. In addition certain special and commercial tests are applied, as Bechi test, Baudouin test, free acid, spontaneous combustion, and drying test. Specific Gravity. This is usually determined either by the Westphal balance (page 36) or by the picnometer. A two-necked flask of fifty cubic centimeters' capacity, having a thermometer carefully ground into one neck, the second one being a narrow tube bearing the mark, is most suitable. This is filled with the oil to be examined, cooled to 15.5 C., 1 the excess of oil removed and weighed. If the weighings be made to 0.5 milligram and a correction applied for the expansion of the glass by the differ- ence in temperature, =15.5 4 = 11. 5 =0.025 per cent, of the value obtained, the determination is accurate to 0.00002. 2 1 Allen (Organic Analysis, 33) states that a correction of 0.00064 can be made for each variation of 1 C. 2 Wright, J. Soc. Chem. Ind., 11, 300 (1892). 4 49 50 PHYSICAL AND CHEMICAL TESTS. For the determination of the specific gravity of small quantities of oil, the arseopicnometer of Eich- horn 1 may be used. Still more satisfactory results can be obtained by weighing one or five cubic centi- meters of the oil carefully measured from an accu- rately calibrated pipette. Or a mixture of alcohol and water can be made until a drop of oil will stay in any position in it, and its specific gravity determined. Valenta Test. 2 Although considered by some to be unreliable, yet as the indication given by this test may be of value, it is barely worth the trouble of execution. It depends upon the solubility of the oil in glacial acetic acid. Enough oil is poured into a test-tube to fill it to the depth of about one inch, the exact height being marked by the thumb; an equal quantity of glacial acetic acid is poured in, that is, until the acid reaches the point indicated by the thumb. A light thermometer is placed in the tube, and it is heated until the oil dissolves, shown by the liquid becoming homogeneous. The tube is now allowed to cool, and the point noted at which it begins to become thoroughly turbid. Castor oil is soluble at ordinary temperatures, while rape-seed and other cruciferous oils are usually insoluble even at the boiling point of the acid. The temperatures at which other oils become turbid are given in Table VIII. 1 Z. anal. Chem., 30, 216 (1891). 3 Valenta, Dingier polyt. J., 253, 418 ; also J. Soc. Chem. Ind., 3, 643 (1884). ANIMAL AND VEGETABLE OILS. 51 Elaidin Test. Although this is not a quantita- tive test, yet its ease of application and the con- clusions which may be drawn from it render it valuable. It depends upon the change of the liquid olein into its solid isomer elaidin, and is especially applicable to olive and lard oils. Manipulation. Five grams of the oil are weighed 1 within two drops into a cordial glass, seven grams of nitric acid, specific gravity 1.34, are then weighed into it, 1 and two pieces of copper wire (0.6 to 1.0 gram) added. Place the glass in a pan of cold water at about 12 C., and stir with a short glass rod about twenty to thirty turns, not only with a rotary movement but also with an up-and-down motion, so as to mix the oil and the evolved gas thoroughly. When the wire has dis- solved, add a second piece and stir as before. This second addition should furnish gas enough if the liquid has been kept cool and the stirring has been thorough. At the end of the first hour pure lard oil will usually show flakes of a wax-like appearance, and upon standing without disturbance and at the same temperature for another hour, the oil will have changed to a solid white cake hard enough to bear several ounces' weight or admit of lifting the glass and contents by the glass rod. Most of the fish and seed oils yield a pasty or buttery mass separating from a fluid portion, 1 Not on the analytical balance. 52 PHYSICAL AND CHEMICAL TESTS. whereas olive, almond, peanut, lard, sperm, and sometimes neat's-foot oil, yield a solid cake. Instead of using nitric acid and copper, sulphuric acid of 46 Baume, containing a little nitric acid and saturated at C. with nitric oxide, may be employed. A test should always be made at the same time with an oil of undoubted purity. Notes. If the oil be stirred too much or too frequently, or is too warm, it has no opportunity to form a hard cake. Hiibl states that all attempts to make the test a quantitative one have resulted in failure. Mercury can be used instead of copper. Cailletet's method, 1 in which a smaller quantity of oil is used and sulphuric and nitric acids allowed to act upon it in a boiling water-bath, cannot, in the experience of the writer, be depended upon to give reliable results. Maumene Test. While this, like the preceding, is not a quantitative test, yet the indications afforded by it are of more value in many cases than those obtained by quantitative methods, as, for example, the saponification value. It depends upon the heat developed by the mixing of the oil with strong sulphuric acid. This takes place in a small beaker seven and one half to nine centi- meters deep and of one hundred and fifty cubic centimeters' capacity, packed in an agate-ware cup with dry felt or cotton waste packing. 1 Milliau, J. Am. Chem. Soc., 15, 156 (1893). ANIMAL AND VEGETABLE OILS. 53 Manipulation. Fifty grams of the oil are weighed 1 into the beaker to within two drops, and its tem- perature noted by a thermometer. Ten cubic centimeters of sulphuric acid are now run gradu- ally into the oil, allowing the graduate to drain five seconds, the mixture being stirred at the same time, and the stirring continued until no further increase in temperature is noted. The highest point at which the thermometer remains constant for any appreciable time is observed, and the difference between this and the initial tempera- ture is the "rise of temperature." This varies with the strength of the acid employed, and to secure uniformity 2 the results should be expressed by dividing the rise of temperature with the oil by the rise of temperature with water, and multiply- ing by one hundred. This is called the "specific temperature reaction." The rise of temperature with water is determined in the same manner as with oil, using the same vessel. Notes. In performing this test it is important that the oil and acid be of the same temperature, attained by keeping them beside each other. The strength of acid should be as far as possible the same; it should be determined not by specific gravity, but by titration, as one hundred per cent, and ninety-four and three-tenths per cent, acid have the same specific gravity. 1 Not on the analytical balance. 2 Tortelli, J. Soc. Chem. Ind., 23, 668 (1904), is unable to secure uniformity in this way. 54 PHYSICAL AND CHEMICAL TESTS. For concordant results the conditions should be the same, and the same apparatus should be used. In case the test is to be applied to a drying oil, it should be diluted one-half with a mineral oil, 25 paraffine, for example, thoroughly mixing them. The "rise of temperature" is then, the rise of tem- perature of mixture minus half the rise of tempera- ture of fifty grams of mineral oil, multiplied by two. It is advisable to make a test at the same time with an oil of known purity. Results should agree within two per cent. By the use of the Hubl formula, p. 62, substituting thermal values, results comparable with those obtained with the iodine value can be obtained. Sherman, Danziger, and Kohnstamm 1 have studied this method with the idea of eliminating the errors. Rather than dilute the oil with a min- eral oil they dilute the acid, using one of eighty- nine per cent. The results obtained are a little lower for vegetable oils and a little higher for ani- mal oils than those usually found with the strong acid as employed by Thomson and Ballantyne- Mitchell 2 uses an inert diluent carbon tetrachlo- ride in a vacuum-jacketed tube and one-fifth the quantities; all oils are diluted. He finds that the results obtained are in close agreement with the bromine thermal values; further, that the test may be of use in determining the degree of oxidation of fats and oils, the figures becoming greater with the age of the oil. 1 J. Am. Chem. Soc., 24, 266 (1902). 1 Analyst, 26, 169 (1901). ANIMAL AND VEGETABLE OILS. 55 Data upon various oils will be found in Table VIII. REFERENCES. MAUMENE, Compt.-Rend., 35, 572 (1852). ELLIS, J. Soc. Chem. Ind., 5, 361 (1886). THOMSON and BALLANTYNE, J. Soc. Chem. Ind., 10, 234 (1891). RICHMOND, Analyst, 20, 58 (1895). MUNROE, Am. Pub. Health Ass'n, 10, 236 (1884). Heat of Bromination Test. This test, which was proposed by Hehner and Mitchell, 1 consists in observing the rise of temperature when bromine is added to a solution of the oil in chloroform. It occupies a middle position between the Maumene, being more accurate than it, and the Hiibl, than which it is less delicate; by multiplying by a factor, different for each instrument, the results obtained can be expressed in figures, which are a close ap- proximation to those obtained by the Hiibl method. The process has not found extensive application, and for a description of the method of execution reference may be had to articles by Wiley, J. Am. Chem. Soc., 18, 378 (1896), and Gill and Hatch, id., 21, 27 (1899). Iodine Number or Value. This is the percent- age of iodine absorbed by an oil; the method de- pends upon the fact that different oils absorb different amounts of the halogens; the process is mainly one of addition, although small quantities of substitution products are formed. For example, the unsaturated body olein, (C 17 H 33 COO)3C 3 H 5 , 1 Analyst, 20, 146 (1895). 56 PHYSICAL AND CHEMICAL TESTS. when brought in contact with iodine takes up six atoms and forms the addition product, di-iodo stearin, (C 17 H 33 I 2 COO) 3 C 3 H 5 . Palmitin, (C 15 H 31 - COO) 3 C 3 H 5 , when similarly treated, forms no addi- tion product, but a small quantity of the substitu- tion product, iodo-palmitin, (C 15 H 30 ICOO) 3 C 3 H 5 , and the hydrogen displaced unites with the iodine to form hydriodic acid. The quantity of hydriodic acid thus formed is a measure of the amount of substitution. 1 1. HANUS'S METHOD. Manipulation. From 0.12 to 0.15 gram of a drying oil, 0.2 to 0.3 gram of a non-drying oil, or 0.6 to 0.7 gram of a solid fat, is accurately weighed into a dry two hundred cubic centimeter bottle. This should be of colorless glass and be provided with a well-ground stopper. This is best effected by pouring out about five grams of the oil into a No. 1 beaker containing a short stirring rod, and setting it into a watch-glass upon the pan of the analytical balance. The whole system is weighed, the beaker removed, and several drops of oil transferred to the bottle by dropping down the rod, being careful that no oil touches the neck. Eight drops are approximately 0.2 gram. The beaker is replaced in the watch-glass and the system again weighed, the difference in weight being the amount of oil in the bottle. The oil is dissolved in 10 cc. of chloroform, 30 cc. of the iodine solution (Appendix, " Reagents") added, best from a burette, and allowed to 1 McDhiney, J. Am. Chem. Soc., 16, 275 (1894). ANIMAL AND VEGETABLE OILS. 57 stand with occasional shaking for fifteen minutes; with oils of an iodine number of less than 100, ten minutes suffices; 15 cc. of potassium iodide solution 1 are added and the solution titrated, with or without the addition of starch, with sodium thiosulphate until the halogen disappears. At the same time at which the oil was prepared two " blanks" should be prepared similarly in every way to the actual tests, except in the addi- tion of the oil, and treated in every respect like them; the strength of the thiosulphate solution should also be determined the same day on which this test is carried out. Standardization of the Thiosulphate Solution. Ten cubic centimeters of potassium iodide and one hundred cubic centimeters of water are poured into the Erlenmeyer flask; twenty cubic centi- meters of the bichromate solution, equivalent to 0.2 gram of iodine, are now measured in with a pipette, and to this five cubic centimeters of strong hydrochloric acid added and the mixture shaken for three minutes. It is now titrated with the thiosulphate solution until the yellow color of the iodine has almost disappeared; starch paste is now added, and the titration continued until the deep- blue color of the solution changes to a sea-green, due to CrCl 3 , which is usually brought about by the addition of a single drop. The reactions involved are: 1 This is the original method. Tolman adds here 100 cc. water as in the Hiibl method. 58 PHYSICAL AND CHEMICAL TESTS. KAA + 14HC1 = 2CrCl 3 + 2KC1 + 7H 8 O + 30,; 3C1 2 + 6KI = 6KC1 + 3I 2 ; 6Na 2 S 2 O 3 + 3I 2 = 3Na 2 S 4 O c + 6NaI. Notes. Wijs 1 uses iodine chloride instead of bromide; it is more troublesome to prepare and gives results about 1.2 points higher. 2 Either of these methods has the advantage over HiibPs, first, that the solutions keep better, remaining prac- tically unchanged for several months; secondly^ that the action is about sixteen times as rapid, it being completed in fifteen minutes; thirdly, that the solutions are cheaper. Acetic acid cannot be displaced by carbon tetra- chloride as a solvent, as the last traces of iodine are difficult to remove from it. The acetic acid used should be at least 99.5 per cent, and show no reduc- tion with potassium bichromate and sulphuric acid. 2. HUBL'S METHOD. Manipulation. The oil is weighed out as in 1, into three hundred cubic centimeter bottles, except that about twenty-five per cent, more may be used. The oil is now dissolved in ten cubic centimeters of chloroform, thirty cubic centimeters of iodine and mercuric chloride solution added, the bottle placed in a dark closet, and allowed to stand, with occasional gentle shaking, for four hours. If the solution becomes nearly decolorized after two hours, an additional quantity should be added. ^erichte, 31,752 (1898). 2 Tolman and Munson, J. Am. Chem. Soc., 25, 244 (1903). See Appendix, Table XIII. ANIMAL AND VEGETABLE OILS. 59 One hundred cubic centimeters of distilled water and twenty cubic centimeters of potassium iodide are added to the contents, and the excess of iodine titrated with sodium thiosulphate. If at this point a red precipitate (HgI 2 ) is formed, more potassium iodide should be added. As the chloroform dis- solves some of the iodine, the titration can proceed until the chloroform layer is nearly colorless, then the starch solution is added, and the operation con- tinued to the disappearance of the blue color. "Blanks" should be titrated as with the fore- going process, page 57. Notes. The method was proposed by Cailletet in 1857, made use of by Mills and Snodgrass 1 in 1883, using, however, bromine and carbon bisulphide, and described in almost its present form by Hiibl. 2 The chief factors in its execution are (1) strength of the iodine solution; (2) the quantity used; and (3) the length of its time of action. I. The Strength of Iodine Solution. According to HiibPs original memoir, the solutions can be kept indefinitely when mixed. Fahrion 3 states that the solution deteriorated as much as from seventeen to twenty-three per cent, in eight days. Ballantyne 4 confirms the deteriora- tion, but finds it much less, five to eight per cent. 1 J. Soc. Chem. Ind., 2, 435 (1883). 'Dingier polyt. J., 253, 281; also J. Soc. Chem. Ind., 3, 641 (1884). 3 J. Soc. Chem. Ind., 11, 183, abstr. (1892). Id., 13, 1100, abstr. (1894). 60 PHYSICAL AND CHEMICAL TESTS. in thirty-eight days. This weakening of the solu- tion is probably due to the hydriodic acid formed by the action of the iodine upon the alcohol. 1 The mercuric chloride acts apparently as a carrier of iodine, as the reaction takes place very slowly without it. (Gantter.) 2 Waller 3 finds that the addition of fifty cubic centimeters HC1, specific gravity 1.19, to the mixed iodine solution preserves it for months. Of the other metallic chlorides, CoCl 2 gives the highest true iodine value, MnCl 2 , MnBr 2 , and NiCl 2 cause practically no addition. (Schweitzer and Lungwitz.) 4 2. The Quantity of Iodine Solution used. The mixed iodine solution as made up should require about fifty-three cubic centimeters of the thiosul- phate. Before using, a rough titration should be made, and if it be much weaker than this, a pro- portionately larger amount added. The action of a large excess of iodine is to increase the substitu- tion rather than addition; increase in temperature or in time produces the same effect. 5 The excess of iodine recommended is from one hundred and fifty to two hundred and fifty per cent.; some observers recommend from four hun- dred 6 to six hundred per cent. 7 1 J. Soc. Chem. Ind., 14, 130 (1895). 2 Id., 12, 717, abstr. (1893). 'Chem. Ztg., 19, 1786, 1831 (1895). 4 J. Soc. Chem. Ind., 14, 1031 (1895). 6 J. Soc. Chem. Ind., 12, 717, abstr. (1893). Id., 14, 1031 (1895). 7 Holde, Mitt. kgl. Techn. Versuchs., 9, 81 (1891). ANIMAL AND VEGETABLE OILS. 61 3. Length of Time. Two hours is sufficient for olive oil, tallow, and lard, while for linseed oil, balsams, and resins twenty-four hours should be allowed. 1 Waller 2 thinks that the " iodine number" is really the sum of changes in the fat due to absorption of iodine, oxygen, and chlorine. The two latter come from the interaction of the iodine, and mercuric chloride setting free chlorine, which sets free some oxygen from the water. Schweitzer and Lungwitz 3 obtain what they term "the true iodine value" by acting upon the oils for twenty-five minutes at 45 C. with iodine dissolved in carbon bisulphide and in the presence of a considerable quantity of mercuric chloride. Practically no hydriodic acid is formed under these conditions, and yet in the case of oleic acid it ab- sorbs more than the theory requires. They have studied further the effect of various sol- vents for iodine instead of ethyl alcohol, as methyl alcohol, ether, carbon tetrachloride and bisulphide. Ingle 4 has shown that the free acid formed during the process is due to the action of water upon the iodochlorides. Some of these are reduced by potas- sium iodide with liberation of iodine and conse- quent reduction in the iodine absorption. Iodine chloride is the active agent, and not hypoiodous acid. 1 Dieterich, J. Soc. Chein. Ind., 12, 381 (1893). 2 Analyst, 20, 280, (1895). 3 J. Soc. Chem. Ind., 14, 1031 (1895). J. Soc. Chem. Ind., 21. 587 (1902). 62 PHYSICAL AND CHEMICAL TESTS. Gill and Adams, 1 using a solution of iodine and mercuric iodide in absolute methyl alcohol, have diminished the amount of substitution that takes place. Oleic acid added the theoretical amount of iodine, and even stearic acid about seven per cent. For the calculation of the percentage of adulter- ation of one oil by another, Hiibl gives the follow- ing formula: 2 "Let x = percentage of one oil and y = percent- age of the other oil, further, m = iodine value of pure oil x, n of pure oil y, and 7 of the sample under examination, then x _100 (7 n) in n He further states that the age of the oil, provided it be not rancid or thickened, is without influence on the iodine value. Ballantyne 3 finds that light and air diminish the iodine number. As might be expected, the iodine value is inversely proportional to the cold test. The method, as will be seen, is a conventional one, and the best results will be obtained by using mea- sured quantities of reagents and carrying through the process in the same manner every time. 4 The calculation is perhaps most easily made as follows: Subtract the number of cubic centimeters 1 J. Am. Chem. Soc., 22, 13 (1900). 'Dingier polyt. J., 253, 281 (1884). 3 J. Soc. Chem. Ind., 10, 31 (1891). 4 If, for example, the water be added before the iodide solution, the iodine number is changed by 0.3 per cent. ANIMAL AND VEGETABLE OILS. 63 of thiosulphate used for the titration of the oil from that obtained by titrating the blank, this gives the thiosulphate equivalent to the iodine absorbed by tjie oil. Multiply this number (of cubic centi- meters) by the value of the thiosulphate in terms of iodine, and the result is the number of grams of iodine absorbed by the oil; this divided by the weight of oil used and multiplied by one hundred gives the iodine number. In case it be desired to recover the iodine used, reference may be had to an article by Dieterich, abstracted in the Jour. Soc. Chem. Ind., 15, 680 (1896). Oxidized Oils Iodine Number of. To find the original iodine number of a semi-drying or non- drying oil which has been altered by atmospheric oxidation, add 0.8 to the iodine number found on the altered sample for each increase of 0.001 in (15 5 C \ * taken at ' ] lo.o u./ Bromine Number or Value. The iodine method just described has, among others, the disadvantage that it fails to distinguish between addition and substitution; this is sometimes of importance, and to accomplish it Mcllhiney 2 makes use of the bro- mine absorption. Manipulation. From 0.2 to 0.3 gram of a drying oil, 0.4 to 0.5 of a non-drying oil, or 1.0 to 1.2 grams of a solid fat, are accurately weighed into the Sherman and Falk., J. Am. Chem. Soc., 27, 608 (1895). J. Am. Chem. Soc., 21, 1084 (1899). 64 PHYSICAL AND CHEMICAL TESTS. three hundred cubic centimeter bottle, as in the iodine number (page 58). The oil is dissolved in ten cubic centimeters of carbon tetrachloride, and twenty cubic centimeters of bromine solution (Appendix, Reagents) added, best from a burette. After allowing it to stand two minutes by the watch, twenty or thirty cubic centimeters of potassium iodide are added, in the manner described below, the amount depending upon the excess of bromine. To prevent loss of bromine and hydrobromic acid, a short piece of thin and wide rubber tubing "bill tie tubing" is slipped over the lip of the bottle, thus forming a well around the stopper; some of the iodide solution is poured into this and the bottle cooled in cracked ice. Upon removing the stopper the solution is sucked into the bottle, it is shaken to insure the solution of the vapors, and the remainder of the reagent added. The iodine liberated is titrated by sodium thiosulphate in the usual way. When this titration is finished, five cubic centi- meters of the potassium iodate solution are added and the titration repeated. The iodine liberated in this reaction is equivalent to the hydrobromic acid present. Blank determinations should be made with the reagents used, as with the iodine number. Notes. Oftentimes, particularly with resins, emulsification of the solution takes place, masking the end point. This can be prevented by the addi- tion of fifty or a hundred cubic centimeters of a ten per cent, solution of salt. ANIMAL AND VEGETABLE OILS. 65 In case ice be not at hand, the vapors will prob- ably be completely absorbed by passing through the iodine solution in the rubber well. The reactions involved, in addition to those on pages 56 and 58, are: Palmitin. (C 15 H 31 COO) 3 C 3 H 5 + 3Br 2 = (C 15 H 30 BrCOO) 3 C 3 H 5 + 3HBr. 3HBr + SKI = 3KBr + 3HI. 6HI + KIO 3 = 3I 2 + 3H 2 O + KI. The calculation is similar to that followed in the iodine number (page 62). The percentage of bromine found as hydrobromic acid is called the bromine substitution figure, and the total percentage absorbed, less twice the bromine substitution figure, gives the bromine addition figure. The method has the further advantages that it is rapid, the bromine solution is permanent and inexpensive. For data upon various oils, see Table XII. Saponification Value. This is expressed by the number of milligrams of potassium hydrate necessary to saponify one gram of the oil. It is called from the originator " Koettstorf er i number or value, " also " Saponification number, " and must not be con- founded with " Saponification equivalent" as proposed by Allen, 2 which is the number of grams of oil saponified by 56.1 grams of potassium hydrate. Manipulation. One to two grams of the oil are weighed out into a two hundred cubic centimeter 1 Z. anal. Chem., 18, 199 (1879). 2 Commercial Organic Analysis, 2, 40. 66 PHYSICAL AND CHEMICAL TESTS. Erlenmeyer flask (as in the iodine value, q. v., page 56) and saponified by twenty-five cubic centimeters alcoholic potash accurately measured from a burette, by heating upon a water-bath, a one-inch funnel being inserted in the flask. When the saponification is complete, shown by the homogeneity of the solution, a few droops of phenolphthalein are added and the excess of alkali titrated with hydrochloric acid. Two blank determinations of the strength of the potassium hydrate must be made simultaneously, by heating 25 c.c. under the same conditions as when mixed with the oil and for the same length of time. Notes. Many prefer to cork the flasks tightly and tie down the stoppers, thus saponifying under pressure; others make use of a return flow con- denser, oftentimes merely a long glass tube. Smetham 1 adds twenty cubic centimeters of ether and finds that it aids saponification. Hen- riques 2 uses three to four grams of oil, twenty-five cubic centimeters of petroleum ether, and twenty- five cubic centimeters of normal alcoholic potash, saponifying in the cold by allowing to stand over night; the advantage consists in preventing the change in the solution by boiling. Mcllhiney 3 has applied the process to dark-col- ored substances by making use of the principle 1 Analyst, 18, 193 (1893). Z Z. angew. Chemie, 721 (1895). 3 J. Am. Chem. Soc., 1 6, 409 (1894). For a discussion of the theory of the process, see Lewkowitsch, J. Soc. Chem. Ind., 17, 1107 (1898). ANIMAL AND VEGETABLE OILS. 67 that when ammonium chloride is added to a neutral soap solution, and the mixture distilled, the amount of ammonia freed is equivalent to the quantity of alkali combined with the fatty acids. As a description of the process is beyond the scope of the present volume, reference must be had to the original article. As ordinarily prepared, the alcoholic potash solution turns rapidly reddish-brown, so that it is very difficult to note the end point. This trouble can be partially avoided by adding a drop or two of the solution to the diluted indicator contained upon a tile after the manner of the titration of iron by bichromate. As the color is probably due to the polymerization of the aldehyde formed by the oxidation of the alcohol, it is more satisfactory to use for the preparation of the potash solution an alcohol which is practically aldehyde free. This is best made, according to Dunlap, 1 as follows: one and one-half grams of silver nitrate are dis- solved in 3 cc. water, added to one liter of alcohol and thoroughly shaken; three grams of potassium hydrate are dissolved in 15 cc. warm alcohol and, after cooling, added to the alcoholic silver nitrate and thoroughly shaken again, best in a tall bottle or cylinder. The silver oxide is allowed to settle, the clear liquid siphoned off and distilled. Alcoholic potash made up from this, using the so-called " potash by alcohol/' will give a solution which will remain water-white for weeks. 1 J. Am Chem. Soc., 28, 397 (1906). 68 PHYSICAL AND CHEMICAL TESTS. The writer has found, if the stock solution be kept under an atmosphere of hydrogen, that the coloration by standing is almost entirely prevented. Detection of Unsaponifiable Oils. The qualita- tive detection takes place by observing the be- havior of the solution obtained by boiling the oil with alcoholic potash when diluted with warm water. Any unsaponifiable material will manifest itself as oily drops in the clear alcoholic solution, or as a whitish cloud on the addition of water. The quantitative determination may take place in two ways: 1. From the saponification number. 2. By gravimetric methods. 1. From the Saponification Number. By Table VIII it will be noticed that, except for Castor, Rape, and Sperm oils, the saponification number averages 193. If the number found be divided by this figure, the percentage of saponifiable matter will be obtained; this subtracted from 100 will give the unsaponifiable matter. This method gives no idea of the kind of saponifiable matter. 2. By Gravimetric Methods. The procedure is essentially that of Spitz and Honig : * Ten grams of the oil are boiled fifteen minutes at a return-flow condenser with fifty cubic centimeters of five per cent, alcoholic potash; 2 forty cubic centimeters of water are added and the boiling repeated. The liquid is allowed to cool, washed into a separatory 1 Z. ang. Chem., 19, 565 (1891). 2 The potash is made by dissolving purified potash in the smallest possible quantity of water and adding absolute alcohol. ANIMAL AND VEGETABLE OILS. 69 funnel with fifty per cent, alcohol and fifty cubic centimeters of 86 gasolene, thoroughly shaken and allowed to stand. The gasolene layer should sepa- rate clearly and quickly from the soap solution and the latter is drawn off; the gasolene is washed two or three times with fifty per cent, alcohol to extract any soap, and these washings added to the soap solution. This latter is extracted until upon evap- oration the gasolene leaves no stain upon paper, care being taken to wash the gasolene extracts each time with fifty per cent, alcohol; three extractions with gasolene are usually sufficient. The gasolene is distilled from these extracts, the residue heated until the gasolene odor disappears, and weighed. From the appearance of the residue some idea of the kind of unsaponifiable matter can be obtained. This in the case of sperm oil will be mainly solid alcohols, probably of the ethylene series. According to Schicht and Halpern 1 this method is open to the following errors: incomplete saponi- fication, incomplete extraction, solubility of soaps in the solvent, and the solubility of the unsaponi- fiable matter in the washing solution. Their im- proved method is as follows: five grams fat with three grams solid caustic potash dissolved in a little water and 25 cc. absolute alcohol are boiled half an hour under a reflux condenser. After cooling 25 cc. of 10 per cent. KC1 are added and the solu- 1 Chem. Ztg., 31, 279 (1907). 70 PHYSICAL AND CHEMICAL TESTS. tion is then shaken four times with 200 cc. petro- leum ether distilling under 60. The petroleum ether is evaporated and, without washing, the residue is dissolved in 25 cc. absolute alcohol and the solution made slightly alkaline with normal alkali; 25 cc. of 10 per cent. KC1 are added and the shaking with petroleum ether repeated. The petroleum ether solution is shaken with 100 cc. of 50 per cent, alcohol and the wash solution with 100 cc. petroleum ether, which is afterwards washed with 100 cc. of 50 per cent, alcohol. After combin- ing the extracts the petroleum ether is driven off and the residue dried and weighed. Notes. Care should be taken to use gasolene which leaves no residue on evaporation at 100 C. Identification of the Unsaponifiable Matter. The unsaponifiable matter is either liquid or solid: in case it is liquid, it may be (1) hydrocarbon oils, either mineral, or formed by the distillation of waste fats, as wool grease, Chapter VIII; or (2) tar oils, "dead oils," etc., obtained by the distillation of coal tar; or (3) rosin oils, p. 118. If it be a question of one of these three, the spe- cific gravity will usually decide it; that of the hydrocarbon oils is 0.855 to 0.930, of the rosin oils 0.96 to 0.99, while the tar oils are heavier than water. Rosin oils would be shown by the Lieber- mann-Storch test, p. 120; a mixture of mineral and tar oils would be identified by treatment with an equal quantity of nitric acid, sp. gr. 1.45, both previously cooled to 15 C., and noting the rise ANIMAL AND VEGETABLE OILS. 71 of temperature. Mineral oils give a very slight rise, being paraffines, while the tar oils belong to the benzole series and are more easily nitrated. Hydrocarbon oils from distilled grease oleines can be identified by their refractive index and rotatory power, p. 145. Solid unsaponifiable matters may be: (4) Paraffine, p. 102. (5) Ceresene refined ozokerite. (6) Higher alcohols of the paraffine series, as cetyl, C 16 H 33 OH, coming from the saponification of sperm oil and other waxes. (7) Cholesterol, C 26 H 43 OH, and its isomers, phy- tosterol, sitosterol, isocholesterol, etc. (8) Lactones, internal anhydrides of oxy acids, as stearlactone, C 14 H 28 CHOHCH 2 CH 2 COOH = C 14 + H 2 0. These may be separated by boiling for two hours with an equal quantity of acetic anhydride; if the substance dissolves and does not precipitate on cooling, higher alcohols are indicated; if a mass of crystals separates out on cooling, cho- lesterol and its isomers, or a mixture of these with the higher alcohols is indicated; if an oily layer remains on top, it is an indication of the presence of paraffine or ceresene. For the complete separa- tion and identification of these reference must be had to Lewkowitsch, " Analysis of Fats, Oils, and Waxes, " as it is beyond the limits of this volume. 72 PHYSICAL AND CHEMICAL TESTS. SPECIAL TESTS FOR CERTAIN OILS. Lewkowitsch 1 states that little reliance can be placed upon the color reactions of the various oils, an opinion in which the writer can cordially concur; with the exception of the Bechi, Baudouin, and Halphen tests, in the majority of cases with a doubtful sample the doubt will still exist after the color test has been performed. Bechi's Test for Cotton-seed Oil. This depends upon the supposition that a substance of an aldehy- dic nature which reduces silver nitrate is contained in the oil. The method is essentially that of Milliau. 2 Fifteen grams of oil are weighed into a No. 6 por- celain dish, using the coarse scales, and heated for about ten minutes upon the water-bath; a mixture of ten cubic centimeters of thirty per cent, caustic soda and ten cubic centimeters of the alcohol is slowly poured upon the oil. The whole is occasion- ally stirred until the mass becomes clear and homo- geneous, and one hundred and fifty cubic centimeters of hot distilled water slowly added so as not to de- compose the soap, and the boiling continued until the alcohol is expelled. Dilute sulphuric acid (1:10) is added to acid reaction, and the separated fatty acids washed three times by decantation with cold water. A portion of these is brought into a large test-tube, fifteen cubic centimeters of alcohol and two cubic centimeters of three per cent, silver 1 J. Soc. Chem. Ind., 13, 617 (1894). 3 J. Am. Chem. Soc., 15, 164 (1893). ANIMAL AND VEGETABLE OILS. 73 nitrate solution are added, the tube is wrapped with brown paper, held in place by an elastic band, and heated, with constant stirring, in the water- bath until one-third of the alcohol is expelled, which is replaced by ten cubic centimeters of water. This heating is continued for a few min- utes longer and the coloration of the insoluble fatty acids observed. The presence of cotton-seed oil in any appreciable proportion causes a mirror- like precipitate of metallic silver, which blackens the fatty acids of the mixture. Notes. The alcohol should be proved free from aldehyde by a blank test. Unless the mixture in the test-tube be thoroughly stirred while heating, it will " bump " and eject the contents. Other methods of procedure consist in applying the test to the oil itself, often after treatment with dilute caustic soda and nitric acid. (Wesson. 1 ) The writer had a case in which the oil gave the test while the fatty acids gave no blackening, showing there was something in the oil itself other than cotton-seed oil which reduced the silver nitrate. Students have no difficulty in detecting a five per cent, adulteration with cotton-seed oil. Dupont 2 thinks that the reduction of silver ni- trate is due rather to sulphur compounds contained in the oil ; by passing steam over the oil he obtained a product containing sulphur and the oil still gave the Bechi test. This work has been repeated and 1 J. Am. Chem. Soc., 17, 723 (1895). a Bull. Soc. Chem. (3), 13, 696; J. Soc. Chem. Ind., 14, 811 (1895); also Charabot and March, Bull. Soc. Chim., 21, 252 (1899). 74 PHYSICAL AND CHEMICAL TESTS. confirmed by the author. 1 It is to be noted that while the fatty acids blacken silver nitrate they do not color cadmium, lead, or copper salts, but reduce mercury compounds. No indication of an aldehyde was noted by the fuchsine or ammonia tests. The supposition that the reducing substance is aldehydic in its nature finds support in the fact that if the oil be heated to 240 2 or be kept for some time 3 it loses this peculiar property. By purifying the acids by the lead salts Tortelli and Ruggeri 4 are able to detect as little as ten per cent, of heated cotton-seed oil. Halphen's Test for Cotton-seed Oil. 5 This depends upon the observation that this oil contains an un- saturated fatty acid which combines with sulphur ; giving a colored compound. 6 Procedure. Ten cubic centimeters of the oil or melted fat are heated, in a large test-tube with a long glass condenser tube attached, with an equal volume of amyl alcohol and of carbon bisulphide solution of sulphur (Reagents), at first with frequent agi- tation, in a steam-bath, and then, after the violent boiling has ceased, in a brine bath (105-110) for forty-five minutes to three hours, according to the quantity of adulterant present, the tube being occasionally removed and shaken. As little 1 Gill and Dennison, J. Am. Chem. Soc., 24, 397 (1902). 2 Holde, J. Soc. Chem. Ind., 1 1, 637 (1892). 3 Wilson, Chem. News, 59, 99 (1889). * J. Soc. Chem. Ind., 20, 753 (1901). 5 Halphen, J. Pharm. Chim. (1897), 390. 8 Raikow, Chem. Ztg., 24, 562, 583 (1900). ANIMAL AND VEGETABLE OILS. 75 as one per cent, will give a crimson wine coloration in twenty minutes. 1 Notes. If the mixture be heated for too long a time a misleading brownish-red color due to burning is produced. The reaction seems to be peculiar to this oil; it is more sensitive with fresh than old fats, and while, by comparison with a blank, one- sixteenth of one per cent, is noticeable, one-fourth of one per cent, is easily detected. Cotton-seed oil which has been heated to 250 does not give the test; the oil is then not available as food. Heating to 200 does not interfere with the test. 2 ' 3 The test is not given by an oil which has been oxidized with sulphuric acid and potassium per- manganate, although such an oil gives the Bechi test. 4 This shows that the two tests are not pro- duced by the same substance. Nor is this test or that of Bechi given by an oil which has been treated with chlorine or sulphurous acid. 5 If treated with the former it is no longer edible; an oil treated with sulphurous acid and washed with alcohol can- not be distinguished from ordinary cotton-seed oil and does not, as already stated, respond to either the Halphen or Bechi test. In this case the test for phytosterol is the only means of determining if it has been added to an animal oil. 1 Oilar, Am. Chem. J., 24, 355; abstr. Anal., 26, 22 (1901). 2 Fischer and Peyan, Analyst, 30, 131 (1905). 3 Soltsien, Z. Offentl. Chem., 5, 135 (1899); J. Soc. Chem. Ind., 18, 865. 4 Raikow, loc. cit. Petkow, Analyst, 32, 123 (1907). 76 PHYSICAL AND CHEMICAL TESTS. Lard from hogs fed on cotton-seed meal shows this reaction strongly, as if it were twenty-five per cent, oil. 1 The butter from cows similarly fed also yields the reaction. 2 The test may be applied to the soaps or fatty acids, provided they are not too deeply colored. The amyl alcohol cannot be omitted nor substi- tuted by ethyl alcohol without impairing the deli- cacy of the test. 3 The compound in the oil cannot be removed by treatment with animal charcoal. 4 Baudouin's, or really Camoin's, test for Sesame Oil. Villavecchia and Fabris 5 apply the test as fol- lows: 0.1 gram sugar is dissolved in ten cubic cen- timeters of hydrochloric acid of specific gravity 1.18 in a test-tube and twenty grams of the oil to be tested added, the whole thoroughly shaken and allowed to stand. In the presence of one per cent, of sesame oil the aqueous liquid will be colored red, 6 due to the action of the f urfurol formed upon the oil. They state that as olive oils of undoubted purity have shown the reaction in the aqueous layer and not in the oily stratum, the color should be looked for in the latter. The sugar may be replaced by 0.1 cubic centi- meter of a two per cent, solution of furfurol and half the quantity of oil used. 1 Soltsien, Z. offentl. Chem., 7, 140 (1901). 3 Wauters, J. Soc. Chem. Ind., 19, 172 (1900). 8 Soltsien, loc. cit., 25, Oilar, loc. cit. 4 Utz, Rev. Fett.-Harz.-Ind., 9, 125 (1902). Z. angew. Chem., 509 (1892); abstr. J. Soc. Chem. Ind., 12, 67; also Kerp, Analyst, 24, 246 (1899). "Ibid. (1893), 505; abstr. Analyst, 19, 47. ANIMAL AND VEGETABLE OILS. 77 Milliau * saponifies as in the Bechi test and dries the acids at 105. Lewkowitsch 2 states that this is a needless complication. Da Silva 3 states that this test has given colors with certain Portuguese olive oils. Kreis 4 states that the active or color-giving constituent is probably phenolic in its nature. The reaction is given by other substances, 5 as vanillin, oil of cloves, and cinnamon; this should be borne in mind in testing oils which have been extracted from confec- tionery. Rancid fats prevent the coloration; it can, however, be brought about even in rancid fats by the addition of an equal quantity of cotton-seed oil. 8 Bach's Test. According to 0. Bach, 7 the acids obtained from rape-seed oil are completely insoluble in David's alcoholic acetic acid, in the proportion of one to fifteen, by volume; those from cotton- seed, peanut, sesame, and sunflower oil dissolve on heating. Those from the last oil separate as a granular precipitate at 15, while from the other three they gelatinize. The acids from olive oil are completely soluble at the ordinary temperature. David's acid is made by mixing twenty-two cubic centimeters of fifty per cent, acetic acid (by volume) with thirty cubic centimeters of alcohol, sp. gr. 0.817, 92.07 per cent, (by weight). 1 J. Am. Chem. Soc., 15, 162 (1893). '"Oils, Fats, and Waxes." 3 J. Soc. Chem. Ind., 17, 275 (1898). 4 Chem. Ztg., 27, 316 (1903). 5 Gerber, Analyst, 32, 90, (1907). 9 Lauff and Hinsmann, Chem. Ztg., 31, 1023 (1908). 7 Allen, "Commercial Organic Analysis, ' ' vol. ii., pt. 1, p. 128 (1899). 78 PHYSICAL AND CHEMICAL TESTS. FIG. 6, Notes. The author has found that Bach's obser- vation cannot be implicitly relied upon, as some rape-seed oils yield acids which are soluble in David's mixture. Free Acid Test. About ten grams of oil are weighed (to centigrams) into a 250 cubic centimeter Erlen- meyer flask, sixty cubic centimeters of neutral alcohol (Reagents) added, the mixture warmed to about 60 C., and titrated with potas- sium hydrate, using phenolphtha- lein, the flask being frequently and thoroughly shaken. The result is conventionally reported in per cent, of oleic acid; 1.0 cubic centi- meter KOH is equivalent to 0.047 gram oleic acid. Spontaneous Combustion Test. Mackey's Apparatus. The appa- ratus, 1 - 2 Fig. 6, consists of a cylin- drical copper water-bath 7 inches high and 4 inches in diameter (inside measurements), surrounded with a half-inch water- jacket. The cover is packed with asbestos and carries the draft tubes A and B, \ inch in diameter and 6 inches long, which cause a current of air to be sucked down B and up A, thus ensuring a circulation of air in the apparatus: C is a cylinder made of 24-mesh wire gauze 6 inches high and 1J inches in diameter Mackey's apparatus. 1 Mackey, J. Soc. Chem. Ind., 15, 90 (1896). 'Gill, id., 26, 185(1907). ANIMAL AND VEGETABLE OILS. 79 and supported upon a projection from the bottom of the bath. A thermometer projects down into the center of the cylinder; if a metal condenser be con- nected to the water-bath it can be used indefinitely without refilling and without danger of burning out. Seven grams of ordinary bleached cotton wadding are weighed out in a porcelain dish or on a watch- glass, and 14 grams of the oil to be tested poured upon the cotton and thoroughly worked into it, care being taken to replace any oil that is lost. The cotton is then placed in the cylinder, packed about the thermometer so that it occupies the upper 4J inches of the cylinder, and put into the boiling water-bath. After the expir'ation of an hour, the bath having been kept in active ebullition, the tem- perature is read. Any oil which shows a temperature exceeding 100 C. in one hour or 200 C. in two hours should be regarded as a dangerous oil, or liable to pro- duce spontaneous combustion. The following tables show the results obtained in using this apparatus. Temperature C. in Oil Ihr. IJhrs. 1* hrs. Olive (neutral) 97-98 100 101 Cotton-seed 112-128 177-242 194-282 Elaine 98-103 101-115 102-191 Olive fatty acids 102-114 196 Other values obtained were : Temp. Time Iodine Free Acid Oil C. Minutes No. per cent. Olive 234 130 85.4 5.3 Lard 234 75 75.2 Trace OleicAcid 158 188 60.5 Cotton-seed 234 70 108.9 Neutral Linseed 234 65 168.1 Neutral 25 Paraffin.. 97 135 16.2 80 PHYSICAL AND CHEMICAL TESTS. Besides being used for testing oils it can be applied to testing other materials, oily waste, sawdust, or any mixture suspected of causing spontaneous combustion. Other apparatus, particularly that of Ordway, 1 described in earlier editions of this book, while giving trustworthy results, has not been found to give such rapid and concordant results as are obtained with Mackey's. For an account of early experiments along this line reference may be had to papers by Coleman and Dollfus in the Bulletin of the Industrial Society of Mulhouse, 1875 and 1876. "The results 1 of the greatest practical value ob- tained in the use of this apparatus have been, first, determining the cause of fires; and, second, deter- mining the degree of safety of the various oils used in manufacturing. Mineral oil, as is well known, is not liable to spontaneous combustion; and a certain percentage of animal or vegetable oil may be added to mineral oil without materially increasing the danger under ordinary circumstances. This per- centage varies according to the oil; with neat's- foot and first quality lard oil some fifty to sixty per cent, may be used, with cotton-seed not over twenty-five per cent, is allowable. The claim so often made for so-called 'safe' oils, said to have been changed by special and secret processes of refining so as to be no longer dangerous, is easily exposed by this test." 1 Richards, Tech. Quarterly, 4, 346 (1891). ANIMAL AND VEGETABLE OILS. 81 Drying Test. This is, as would be implied, more especially applicable to the drying oils; there are two ways of applying it, exposure of the oil upon finely divided lead (Livache test) and upon a plate of glass. Livache Test. 1 One gram of precipitated lead is spread out in a thin layer on a three-inch flat watch- glass and accurately weighed; 0.5 to 0.6 gram of the oil (twenty to twenty-four drops) are brought upon the lead from a pipette, taking care that the drops do not touch each other, the watch-glass and contents again accurately weighed, and exposed to light and air at ordinary temperature. It is weighed from time to time, the maximum weight being reached in from eighteen to seventy-two hours. The oil that increases most in a given time is considered to be the best drying oil. Lippert 2 confirms Weger's opinion that the Livache test as here carried out is unreliable and advises the use of copper powder instead of lead. This is known as "cement copper," and is prepared similarly to the precipitated lead. Test upon Glass. 3 A few drops of the oil are brought upon a glass plate inclined at about thirty degrees from the horizontal. A test of the oil is made from time to time by touching it with the fingers, the time at which it does not soil them being noted as the point when it is dry. Good oil should dry in three days. 1 Compt. rend., 102, 1167 (1886). 2 Rev.Fett.-Harz.-Ind., 6, 65; abstr. J. Soc. Chem. Ind., 18, 693 (1899). 3 Amsel, J. Soc. Chem. Ind., 15, 222 (1896). 82 PHYSICAL AND CHEMICAL TESTS. Archbutt * makes this test as follows : A piece of polished plate-glass seven centimeters square by four millimeters thick is cleaned and counterpoised on the balance; it is then heated for an hour at 200 C. in an air-bath to thoroughly dry it. It is taken out, laid on a non-conductor, allowed to cool for three or four minutes, and the hot glass thinly painted with the oil to be tested by means of a camel's-hair brush. When the glass is cold it is weighed and sufficient oil added to make it up to 0.1 gram. Two glasses are coated with the sample and two with a standard oil, all placed on a level surface in a large air-bath at 50 C. and heated for nine hours; one set of plates is withdrawn, cooled, and tested by the finger. Good raw linseed is tacky, when tested by the finger when cold, in nine hours and dry in twelve; corn oil is practically dry in fifteen hours, though slightly tacky; cotton- seed, partially dry in eighteen hours and fully dry in twenty-one. Refined rape oil dried in forty-eight hours, and olive oil was sticky after thirteen days. Titer Test. Under this rather misleading title is expressed the solidification point of the fatty acids derived from a fat or oil; it has nothing at all to do with titration, as might be expected. The test is extensively used for the evaluation of fats, and according to the method provisionally adopted by the Association of Official Agricultural Chemists is carried out as follows: 2 J. Soc. Chem. Ind., 18, 347 (1899). 2 U- S. Dept. of Agriculture, Bureau of Chemistry Bulletin No. 107, p. 135 (1907). ANIMAL AND VEGETABLE OILS. 83 (a) STANDARD THERMOMETER. The thermometer must be graduated in tenth degrees from 10 to 60, with a zero mark, and have an auxiliary reservoir at the upper end, also one between the zero mark and the 10 mark. The cavity in the capillary tube between the zero mark and the 10 mark must be at least 1 cm. below the 10 mark, the 10 mark to be about 3 or 4 cm. above the bulb, the length of the thermometer being about 15 inches over all. The thermometer is annealed for 75 hours at 450 C., and the bulb is of Jena normal 16"' glass, moderately thin, so that the thermometer will be quick acting. The bulb is about 3 cm. long and 6 mm. in diameter. The stem of the thermometer is 6 mm. in diameter and made of the best thermometer tubing, with scale etched on the stem, the graduation to be clear-cut and distinct, but quite fine. (b) DETERMINATION. Saponify 75 grams of fat in a metal dish with 60 cc. of 30 per cent, sodium hydroxid (36 Baume") and 75 cc. of 95 per cent, (by volume) alcohol or 120 cc. of water. Boil to dryness, with constant stirring to prevent scorching, over a very low flame or over an iron or asbestos plate. Dissolve the dry soap in a liter of boiling water, and if alcohol has been used, boil for forty minutes in order to remove it, adding sufficient water to replace that lost in boiling. Add 100 cc. of 30 per cent, sulphuric acid 84 PHYSICAL AND CHEMICAL TESTS. (25 Baume*) to free the fatty acids, and boil until they form a clear, transparent layer. Wash with boiling water until free from sulphuric acid, collect in a small beaker, and place on the steam bath until the water has settled and the fatty acids are clear; then decant them into a dry beaker, filter, using the hot-water funnel, and dry twenty minutes at 100 C. When dried, cool the fatty acids to 15 or 20 C. above the expected titer and transfer to the titer tube, which is 25 mm. in diameter and 100 mm. in length (1 by 4 inches) and made of glass about 1 mm. in thickness. Place in a 16-ounce saltmouth bottle of clear glass, about 70 mm. in diameter and 150 mm. high (2.8 by 6 inches), fitted with a cork, which is perforated so as to hold the tube rigidly when in position. Suspend the thermometer, graduated to 0.1 C., so that it can be used as a stirrer, and stir the mass slowly until the mercury remains station- ary for thirty seconds. Then allow the thermometer to hang quietly, with the bulb in the center of the mass, and observe the rise of the mercury. The highest point to which it rises is recorded as the titer of the fatty acids. Test the fatty acids for complete saponification as follows: Place 3 cc. in a test-tube and add 15 cc. of alcohol (9$ per cent, by volume). Bring the mixture to a boil and add an equal volume of ammonium hy- droxid (0.96 sp. gr.). A clear solution should result, turbidity indicating unsaponified fat. The titer must be made at about 20 C. for all fats having a ANIMAL AND VEGETABLE OILS. 85 liter above 30 C. and at 10 C. below the titer for all other fats. REFERENCES. HEFTER, G. Technologie der Fette, Oele, und Wachsarten des Pflanzen und Tierreichs. 4 volumes, 1906 + UBBELOHDE, L. Chemie, Analyse und Gewinnung der Oele, Fette und Wachse. 4 volumes, 1908 + CHAPTER IV. GENERAL CONSIDERATIONS REGARDING LUBRICANTS. Method of Examination of an Unknown Oil. ACCORDING to the results of the viscosity and friction tests, the least viscous oil is to be given the preference. It should be borne in mind, however, that the heat of the journal diminishes the viscosity: for example, at 60 F., if the viscosity of sperm oil be taken as 100, that of 25 paraffine oil is 123; at 100 F. the latter has diminished to 110, and at 250 F. they are practically equal. On account of this change in temperature, as well as the irregulari- ties of the journals, of the feed, and of pressure, a too thinly fluid oil must not be chosen. The following considerations will aid in the selection of a suitable oil. 1. The flashing point of the oil should be above 300 F. 2. The oil should have an evaporation test of less than five per cent. 3. On general principles the most fluid oil that will stay in place should be used. 4. The best oil is that which possesses the greatest adhesion and least cohesion. This condition is ful- filled, first, by fine Mineral Oils; 1 second, Sperm; third, Neat's-foot; fourth, Lard. 1 Except at high temperatures. Doolittle, J. Am. Chem. Soc., 20, 238 (1898). 86 LUBRICANTS: GENERAL CONSIDERATIONS. 87 5. For light pressures and high speeds, Mineral Oils of specific gravity 30.5 Be., flash point 360 F., Sperm, Olive, and Rape (Thurston adds also Cotton-seed), should be employed. 6. For ordinary machinery, Mineral Oils of spe- cific gravity 25 to 29 B<., flash point 400 to 450 F., Lard, Whale, Neat's-foot, and Tallow, also heavy Vegetable Oils, should be used. 7. For cylinder oils, Mineral Oils of specific gravity 27 Be"., flash point 550 F., alone and with small percentages (1 to 7) of Animal or Vegetable Oils, are employed; the latter are Degras, Tallow, Lin- seed, Cotton-seed, and blown Rape. 8. For watches and clocks, clarified Sperm, Jaw, and " Melon" oils should be employed. 9. For heavy pressure and slow speed, Lard, Tallow, and other greases, either by themselves or mixed with Graphite and Soapstone, should be used. 10. For very heavy pressure, solid lubricants, as Graphite and Soapstone, are employed. 11. To resist cold, as, for example, for lubricating air-driven rock-drills, Kerosene has been used. 12. The oil should contain no acid to corrode the shaft or journal; the German railroads l per- mit no more than 0.1 to 0.3 per cent, of acids, calcu- lated as sulphuric anhydride, in their oils. For the action of oils upon metals reference may be had to Table X. 1 Aisinmann, Z. angew. Chemie, 11, 213; abstr. J. Soc. Chem. Ind., 14, 811 (1895). 88 PHYSICAL AND CHEMICAL TESTS. REFERENCES. MILLS, J. Soc. Chem. Ind., 5, 148, 149 (1886). COLEMAN, ibid., 359. REDWOOD, idem, 121-132. DENTON, Trans. Am. Soc. Mech. Engrs., 9, 369 (1888); 11, 1013 (1890). ARCHBUTT and DEELEY, " Lubrication and Lubricants," 48-131. WM. M. DAVIS, " Friction and Lubrication." D. HOLDE, " Untersuchung der Mineral Oele und Fette." Method of Examination of an Unknown Oil. There being no specific tests foAhe different oils, 1 as in the case of the various elementary substances, the analyst should, in attacking an unknown oil, ascertain all possible facts about it, as the source, the use to which it is put, and the cost. A low- priced oil is not likely to be adulterated with one of higher cost. While the prices fluctuate to a consid- erable extent, yet the following table, it is believed, represents the average price of the various oils, the highest priced being given first: 1. Almond. 7. Sperm. 12. Lard. 2. Castor. 8. Whale. 13. Cod. 3. Sesame. 9. Peanut. 14. Cotton-seed. 4. Neat's-foot. 10. Linseed. 15. Mineral. 5. Rape. 11. Tallow. 16. Rosin. 6. Olive. Certain physical properties may aid in the exami- nation. The color is of little assistance, as oils may be colored by the use of the oleates or butyrates of iron or copper. Fluorescence is valuable as indicat- 1 At the present state of our knowledge (1908) we can detect the following oils with certainty: Castor, Cokernut, Cotton-seed, Pea- nut, Rosin, and Sesame. We can be reasonably certain of 25 per cent, of Corn, Rape, and Sperm oils. LUBRICANTS: GENERAL CONSIDERATIONS. ing the presence of mineral oil; this can be shown by placing a few drops of the oil on a sheet of ebonite and observing the bluish color. The odor and taste, as has already been stated, may to experts reveal much about the nature of the oil under examination. Marine animal oils are detected, especially when warm, by their strong "fishy" odor, while neat's-foot, tallow, lard, olive, rosin, and linseed oils each have a well-marked and easily distinguishable odor. Whale oil has a nutty, and rape oil a harsh, unpleasant taste. The specific gravity should next be noted, the oil being exactly at 15 C. The accompanying table shows the groups into which the oils are divided by this criterion: .875-.8S4. .884-.912. .912-.920. .920-.937. .937-.970. Sperm. Oleic Acid. Almond. Lard. Neat's-foot. Olive. Peanut. Rape. Tallow. Corn. Cotton-seed. Fish. Linseed. Poppy-seed. Sesame. Castor. Blown Oils. The elaidin test (page 51) may be applied next, to allow time for the cake to form; it will be followed by the Valenta (page 50) and Maumene (page 52) tests, all of these being done in duplicate. In mak- ing the elaidin test, it is advisable to carry on an experiment under the same conditions with a known sample of lard oil. From the result of the examination up to this 90 PHYSICAL AND CHEMICAL TESTS. time a reasonably good idea of the nature of the oil will have been obtained; the iodine test can now be applied and the percentage of adulteration approximated. The data obtained by the Maumen6 test and specific gravity determination will serve as checks upon this. In case Sesame, Cotton-seed, Peanut, or Rosin oils be suspected, the specific tests for them can be made. The saponification test, unless mineral oil be sus- pected, need rarely be resorted to; the reason being that it would show practically nothing regarding the nature of the oil. This is evident from Table VIII. Of all the oils there given, this constant, excepting Castor (181), Rape (174), and Sperm (135), being about 193. Finally, where the impor- tance of the case will warrant, the analyst is advised to prepare a mixture of the oils, using the propor- tions indicated by the various tests, and subject it to the more rapid tests, as the Specific Gravity, Viscosity, Maumene", and Bromine Number. It should be borne in mind in making out the report that, excepting in the case of the special tests, the results of one test cannot be relied upon to determine the nature of an oil, but the evidence of all the tests here given should be carefully weighed and com- pared before rendering a final verdict. Test for Animal or Vegetable Oils. Animal oils contain cholesterol, C 26 H 43 OH, while vegetable oils contain the isomeric body phytosterol; hence the isolation and identification of these compounds enables one to say with certainty as to the pres- LUBRICANTS: GENERAL CONSIDERATIONS. 91 ence of one class of oil or the other for example as to the presence of fish oil in linseed. The quan- tity of these bodies varies from 0.2 to one per cent. The method is essentially that of Bomer.W Fifty grams of the oil are boiled in a flask with a return cooler with 75 cc. of 95 per cent, alcohol for five minutes and the alcoholic solution separated; this is repeated with another portion of alcohol. The alcoholic solutions are mixed with 15 cc. of 30 per cent, sodium hydroxide and evaporated on a water-bath nearly to dryness in a porcelain dish and the residue shaken out with ether. The ether is evaporated, the residue taken up with a little ether, filtered, again evaporated, dissolved in 95 per cent, alcohol (by volume), and allowed to crystallize slowly. Bomer states that the form of the crystals is more to be relied upon than a determination of their melting point. Cholesterol crystallizes from alcohol or ether in leaflets or rhomboid tables con- taining one molecule of water of crystallization. Phytosterol crystallizes also from alcohol with one molecule of water in needles forming stars or bundles. As a further means of identification, some of the esters should be made and their melting points determined. To this end the crystals above obtained are heated over a low flame in a small porcelain dish covered with a watch-glass, with 2 or 3 cc. of acetic 1 J. Soc. Chem. Ind., 17, 954 (1898). 'Tolman, J. Am. Chem. Soc., 27, 590 (1905). 3 Tolman, Bull. 107, U. S. Dept. Agriculture (1907). 92 PHYSICAL AND CHEMICAL TESTS. or other acid anhydride until it boils: the watch- glass is removed and the excess of anhydride evaporated on the water-bath. The contents of the dish are treated with a small quantity of absolute alcohol to prevent crystallization, more alcohol added and the solution allowed to crystallize. The crystals are filtered off through a very small filter, washed with a small quantity of 95 per cent, alcohol, dissolved in absolute alcohol, and recrystallized until a constant melting point is obtained. The following table shows the corrected melting points of these alcohols and their esters: Cholesterol. Phytosterol. Alcohol 148-150.8 136-143.8 Acetate 113-114 120-137 Benzoate 145-151 142-148 Propionate 97-98 104-105 Notes. Some directions state, in isolating the cholesterol or phytosterol, to boil with the 30 per cent, sodium hydroxide until one-fourth of the alcohol is evaporated. As a result of repeated experiments this has been found to cut down the yield so much that on a large scale practically none of these bodies, particularly phytosterol, was ob- tained. This agrees with the observation of Lew- kowitsch that by heating cholesterol with normal alcoholic potash, cholesterin hydrate is obtained. The following test will serve to differentiate between cholesterol and phytosterol. 1 A very small *Neuberg and Rauchwerger, abstr. J. Soc. Chem. Ind., 23, 1163(1904). LUBRICANTS: GENERAL CONSIDERATIONS. 93 quantity of cholesterol is warmed with 1.5 cc. absolute alcohol and a trace of isodulcit or rhamnose (^-dimethylfurfural) added. After cooling, an equal volume of concentrated sulphuric acid is added, so as to form a layer below the solution, whereupon a raspberry-colored ring is produced at the zone of contact of the two liquids. On mixing the layers while the tube is cooled in a current of cold water the mixture becomes intensely colored. With phy- tosterol the reaction fails or at most a pink color. Similar reactions are given by abietic acid. As little as one per cent, of cotton-seed has been found in lard, and four per cent, in any oil have been detected by this test. For the means of distinguishing between drying and marine animal oils, see Halphen, J. Pharm. Chim., 14,391 (1901), abstracted J. Soc. Chem. Ind., 21, 74, or Chem. Centralb., 72, ii., 1097 and 1323. PART II. DERIVATION, DESCRIPTION, AND EXAMINATION. DERIVATION, DESCRIPTION, AND EXAM- INATION OF CERTAIN OILS. IN this part the technology and properties of the more commonly occurring oils will be considered under the following heads: 1. Source and Preparation. 2. Physical Characteristics. 3. Chemical Composition. 4. Analytical Constants. 5. Adulterations and their Effects. 6. Uses. The analytical data are the average of the results from many sources; in addition to these the highest and lowest results are often given. The classification of the animal and vegetable oils is that of Lewkowitsch, following in the various groups of oils the order of the iodine values. A. Oils and Fats. Glycerides. 1. VEGETABLE OILS. (1) Drying Oils. (2) Semi-drying Oils. (3) Non-drying Oils. 7 97 EXAMINATION OF CERTAIN OILS. 2. ANIMAL OILS. (1) Marine Animal Oils. a. Fish Oils. 0. Liver Oils. Y. Blubber Oils. (2) Terrestrial Animal Oils. B. Waxes. Non-Qlycerides. LIQUID WAXES. CHAPTER V. PETROLEUM PRODUCTS. CRUDE petroleum varies so much with the locality that any statement about it is only approximate; according to Peckham, 1 the products which may be obtained from Pennsylvania petroleum are about as follows : First. The NAPHTHA DISTILLATE, all that passing over above 60 Baum6, about sixteen and five-tenths per cent. Second. The BURNING OIL DISTILLATE, that pass- ing over between 60 and 36 B6., about fifty-four per cent. Third. The LUBRICATING OIL DISTILLATE, that passing over from 36 to 23 B6., about seventeen and five-tenths per cent. Fourth. PARAFFINE, two per cent. Fifth. COKE AND LOSSES, ten per cent. The Naphtha Distillate. This is fractionated as follows : I. Crude Gasolene, cut at 80 B6., one and five- tenths per cent. II. C Naphtha, between 80 and 68 B6. , ten per cent. III. B Naphtha, between 68 and 64 B6., two to two and five-tenths per cent. 1 S. F. Peckham, 'Report on Petroleum," p. 165; also J. Soc. Chem.Ind., 13,794(1894). 99 100 EXAMINATION OF CERTAIN OILS IV. A Naphtha, between 64 and 60 Be., two to two and five-tenths per cent. Fraction I. is redistilled and the products caught in a mixture of ice and salt, giving: 1 1. Cymogene, 110 to 100 Be., Bpt. 32 F., largely butane, used for ice-machines. 2. Rhigolene, 100 to 90 Be., Bpt. 65 F., largely pentane, used as a local anaesthetic. 3. Petroleum Ether, Sherwood Oil, " Gasolene," 90 to 80 Be., Bpt. 100 to 150 F., largely hexane, used for carburetting air in the various " gas-ma- chines" and in the laboratory for oil and fat ex- traction. 4. Gasolene, Canadol, 80 to 75 Be., Bpt. 150 to 190 F., used for oil extraction on the large scale. Fraction II. is treated with four ounces of oil of vitriol to the gallon in an agitator with mechanical paddles, washed with caustic soda solution, and dis- tilled with steam, yielding: 5. Naphtha, Danforth's Oil, 76 to 70 Be., Bpt. 160 to 210 F., used in street lamps, stoves, torches, and gasolene engines. Fractions III. and IV. are treated similarly to II., giving: 6. Ligroine, 67 to 62 Be., Bpt. 160 to 225 F., 2 used in pharmacy, in the laboratory, and in sponge lamps. 7. Benzine (deodorized), 62 to 57 Be., Bpt. 225 1 Sadtler, "Industrial Organic Chemistry" (1895), p. 30. 2 Freezing point, 147 C. Cabot, J. Soc. Chem. Ind., 26, 813 (1907). PETROLEUM PRODUCTS. 101 to 300 F., used as a substitute for turpentine, for cleaning type, and by dyers and scourers. The Burning Oil Distillate. This is fractionated into : V. Crude Burning Oil, 58 to 40 Be., forty-two per cent. VI. "B" Oil, 40 to 36 Be., seventeen per cent. Fraction V. is treated with acid similarly to II., washed, and distilled as long as the color is good. Three fractions may be obtained: 8. " Export Oil," 110 F., Fire Test (F. T.), shipped to China and Japan. 9. Export Oil, 120 F., F. T., shipped to England. 10. Headlight Oil, 150 F., F. T., 50 to 47 Be., ordinary kerosene. Fraction VI. is treated similarly to V., and on distillation yields: 11. Mineral Sperm, or Lantern Oil, 36 Be., 250 F., Flash point, and 300 F., F. T., used for passenger traffic illumination and in light-houses. The Lubricating Oil Distillate. The residues from the burning oil distillate are distilled with super- heated steam, various fractions being obtained; these are treated with acid, washed, and redistilled, yielding : " Neutral" Oils, 38 to 32 Be., used as "wool oils." Spindle Oils, 32 to 28 Be\ Loom Oils, 29 to 27 Be*. Engine Oils, 27 to 23 Be\ Cylinder Oils, 28 to 25 Be\ 102 EXAMINATION OF CERTAIN OILS. These fractions are filtered through sawdust and salt to remove water, and when too deeply colored through bone charcoal, after the manner of sugar syrups. In addition to these distilled oils there is another class, the paraffine oils, which are obtained by chill- ing and pressing certain distillates, yielding solid paraffine and paraffine oil. A. OILS AND FATS. GLYCERIDES. CHAPTER VI. VEGETABLE OILS. (1) Drying Oils. Linseed Oil. Percentage of oil in seeds 38 to 40. Preparation. Linseed oil is prepared from the seeds of the flax-plant by expression or extraction. The oil receives its name according to the locality where the seed is grown. Calcutta, La Plata, and Western are some of the brands in this market; the first being considered to be the best, although some- times equalled by the last. Properties. It is of a golden-yellow color and high specific gravity, the highest of any fatty oil likely to be used as an adulterant. On exposure to the air it ab- sorbs oxygen often causing spontaneous combustion and dries to a gummy, insoluble substance, linoxyn. Composition. It contains the glycerides of isolino- lenic, linolenic, linolic, 1 oleic, stearic, palmitic, and myristic acids. CONSTANTS. Sp. Gr. 15 C. Maumeng. Elaidin. Iodine. 1 Saponification. .9315-.9371 103-126C. Liquid 170-193 187.6-195.2 90 and solid. 167.6 .934. 111 176 191 1 Hazura and Griissner, Monatsh., 9, 180 (1888). 2 Obtained by Hiibl's method; this is true of this constant throughout the book. 103 104 EXAMINATION OF CERTAIN OILS. Adulterants. Corn, Cotton-seed, Fish, and Rosin oils. All these adulterants lower the constants given and diminish its drying power; Cotton-seed oil would be shown by the Bechi test (page 72) ; Rosin oil by the low Saponification Value, it being un- saponifiable, by the Liebermann-Storch reaction (page 120), and by the rotary power. Fish oil, usually menhaden oil, p. 132, may, if present in large quantity, be detected by its odor when warmed. For the detection of smaller quantities, and par- ticularly of the deodorized oil, resort must be had to the isolation of phytosterol and cholesterol (p. 90). These should be converted into the acetates by boiling with acetic anhydride, recrystallized from absolute alcohol four or five times or until a constant melting point is obtained. Bomer and Winter state that the melting point of the phytosterol acetate crystals from pure linseed oil is 128-129, and that if cholesterol be present a much lower melting point is obtained. Uses. For preparation of paints and as " boiled" and "bleached oil" for preparation of varnishes; by treatment with sulphur chloride for manufacture of rubber substitutes; and for soft soaps. "Boiled Oil." By heating the oil preferably in a steam jacketed kettle from 130 C. upward, with or without the addition of litharge, red lead, lead acetate, manganese dioxide or borate, the oil becomes oxidized, changes color, and dries much more rapidly. The constants of boiled oil are as follows: VEGETABLE OILS. 105 CONSTANTS. 1 Sp. Gr. 15 C. Maumen. Iodine. Valenta. .936-.93S 100 C. 164-178 60-74 C. Bleached Oil. This is an oil prepared, by special processes kept jealously guarded, for the use of varnish-makers. It may be prepared by heating linseed oil hotter than in the preparation of " boiled oil, " to 260 to 300 C., or by forcing oxygen through the oil. CONSTANTS. 1 Sp. Gr. 15 C. Maumend. Iodine. Valenta. .032-.934 104 C. 160 60 C. Mastbaum 2 states that pressed linseed oil has a higher iodine value than extracted because the more fluid portion is pressed out, and further, that the iodine value changes with the age of the oil. Linseed oil for varnish-making and other refined purposes should separate but a small quantity of mucilage when heated to 300 C. The oil should be very rapidly heated to this temperature in a metal vessel, poured into a test-tube, and allowed to cool. A suitable oil shows little or no deposit, whereas a bad one may separate an amount equal in volume to the oil used. Hexabromide Test. This is of great value to determine the purity of a linseed oil. If the yield of hexabromides from a linseed oil is less than twenty per cent., foreign oil is present; fatty acids from genuine linseed oils yield usually from thirty 1 Gill and Lamb, J. Am. Chem. Soc., 21, 29 (1899). 'Mastbaum, Z. angew. Chem., 23, 719; abstr. J. Soc. Chem. Ind., 16, 150 (1897). 106 EXAMINATION OF CERTAIN OILS. to forty-two per cent, of bromides. The bromides of these acids melt at 175-180 to a dear liquid, while those obtained from fish, liver, and blubber oils do not melt even at 200 and change into a dark mass. The test is best performed according to the method of Hehner and Mitchell : * One or two grams of the oil (0.3 gr. fatty acids) are dissolved in 40 cc. of ether to which a few cubic centimeters of acetic acid have been added. The solution is cooled to 5 and bromine added drop by drop (keeping the flask cool) until the color of bromine persists. The mixture is allowed to stand three hours to ensure complete absorption of the bromine, filtered through a weighed asbestos filter, and the precipitate washed successively with 5 cc. each of cooled acetic acid, alcohol, and ether. The precip- itate is dried in a water oven to constant weight. Linseed oil yields from 23 to 38 per cent, of bro- mides; poppy, corn, cotton-seed, almond, olive, and in some cases tung oil, yield none; walnut oil 1.5-2.0, fish oil 49.0-52, Japan fish oil 22, cod-liver oil 30-43, shark-liver oil 19-22, seal oil 27, whale oil 15-25. Boiled oils 2 can be detected by the lower percent- age of bromides obtained in this test; where raw oil gives 24 per cent., boiled oils give from 8.4 to 21. Chinese Wood Oil. Percentage of oil in seeds 35 to 40. Preparation. This oil, called also Japanese Wood oil or Tung oil, is obtained from the seeds of the 1 Analyst, 23, 313 (1898). 3 Lewkowitsch, Analyst, 29, 334 (1904). VEGETABLE OILS 107 Elceococca vernicia, and must not be mistaken for gurjun balsam, also known as wood oil. Properties. It is pale yellow to dark brown, of unpleasant taste and odor. On exposure to light it is slowly changed to a solid fat, owing to the con- version of the elseomargarine into its isomer, elseo- stearine. It dries more rapidly than linseed oil, forming a hard film of little adhesive power to the surface beneath. It does not dry on the surface or in layers, as does linseed. Composition. It consists of the glycerides of oleic and elaeomargaric acids. 1 CONSTANTS. Sp. Gr. 15 C. Iodine. Saponification. .940 155-165.7 190-197 When heated above 200 C. it gelatinizes and then neither melts nor dissolves. Uses. Wood oil cannot be regarded as a substi- tute for linseed oil; when mixed with it, it has given excellent results, especially for out-of-door work. When heated with driers at about 160 C. it has been used to good advantage in the manufacture of oil varnishes and enamel paints. 2 It is used as a floor varnish, in the manufacture of water-proof materials, and products resembling oilcloth. Poppy-seed Oil. Per cent, oil in seeds 40-50. Preparation. Poppy-seed oil is prepared from the seeds of the common poppy. . Bull. Soc. Chim., 26, 286 (1901); Compt. rend., 71, 649; 72,501. 3 Toch, " Chemistry and Technology of Mixed Paints." 108 EXAMINATION OF CERTAIN OILS. Properties. The "cold drawn" oil is colorless or pale golden yellow, that of the second pressing of a reddish color; the taste is pleasant, and it is practi- cally odorless. It dissolves in twenty-five volumes of cold or six of boiling alcohol. CONSTANTS. Sp. Gr. 15 C. Maumene". Iodine. Saponification. .924-.9S7 87 C. 133-143 190-197 .925 138 193 Adulterants. The chief adulterant is Sesame oil, detected by the lower Iodine Value and Baudouin test. Uses. The oil is used as a salad oil and for mixing and grinding artists' colors. Sunflower Oil. Percentage of oil in seeds 30. Preparation. Sunflower oil is obtained from the seeds of the common sunflower. Properties. It is a pale yellow oil of bland taste and pleasant odor. CONSTANTS. Sp. Gr. 15 C. Maumend. Iodine. Saponification. .924-.92G 67-75 C. 118-133 190-194 Gives Bechi but not Halphen or Baudouin test. Uses. For adulterating other oils, as olive, as an edible oil, for burning, soap- and varnish-making. (2) Semi-drying Oils. Corn Oil. Percentage of oil in seeds 6 to 10. Preparation. Corn or Maize oil is prepared by Expression from the germ of the corn separated in VEGETABLE OILS. 109 the manufacture of starch, 1 or from the residues from the fermentation of alcohol. 2 Properties. The former oil is pale to golden yel- low, the latter reddish brown. CONSTANTS. Sp. Gr. 15 C. Maumen(?. Elaidin. Iodine. Saponification. .9215-.927 56-88 C. Pasty. 111-123 188-193 .922 85 115 191 .922 100 124 188 Adulterants. Mineral and Rosin oils. These would be detected by the lowering of the constants (except Specific Gravity), and the latter by the Liebermann-Storch reaction. Composition. It contains the glycerides of pal- mitic, arachidic, oleic, linoleic and, possibly, stearic acids. Uses. For adulterating other oils, as linseed, lard, 4 and olive, and for painting, burning, lubricat- ing, and soap-making, especially soft and transparent soaps. Cotton-seed Oil. Percentage of oil in seeds 25. Preparation. Cotton-seed oil is obtained by press- ing the seeds of the cotton-plant; when first pressed it is ruby-red or black, and is purified by treatment with caustic soda, carrying down the gelatinous sub- stances and color as " cotton-seed foots." The 1 J. Soc. Chem. Ind., 11, 286 (1892). 2 Kriegner, Dingier pol. J. (1895), 39 ; abstr. J. Soc. Chem. Ind., 14, 287 (1895). 3 Boiled corn oil. 4 Its presence can be told by the presence of sitosterol. See articles by Gill and Tufts, J. Am. Chem. Soc., 25, 254 (1903). Also McPherson and Ruth, ibid., 29, 921 (1907). 110 EXAMINATION OF CERTAIN OILS. grades in the market are Summer White and Sum- mer Yellow, and Winter White and Winter Yellow, according to the temperature or season of pressing. Properties. It is pale to deep yellow in color, and absorbs oxygen slowly from the air. Composition. It contains the glycerides of stearic, palmitic, oleic, linoleic acids, and some hydroxy- acids not yet investigated. (Hazura, Fahrion.) CONSTANTS. Sp. Gr. 15* C. Maumen. Elaidin. Iodine. Saponification. .9216-.930 70-90C. Pasty. 101-117 191-196 .922 76 108 Adulterants. It is rarely adulterated. Linseed oil is used for this purpose when the price permits. Uses. For adulterating other oils, as a cooking oil both by itself and when mixed with suet, as "Cottolene," "Cotosuet," etc., and for soap stock; it, however, occasions a browning of the product. Sesame Oil. Percentage of oil in seeds 50 to 57. Sesame oil, known also as Gingili or Teel oil, is prepared from the seeds of the sesame-plant. Properties. It is odorless, of a pale or deep yellow color and pleasant taste. Composition. It contains the glycerides of stearic, palmitic, oleic, and linolic acids, also other bodies 1 the composition of which is not exactly known, to which the color reaction (page 76) is probably due. B6mer, Chem. Centralb., 70, ii. 729 (1899); Kreis, Chem. Ztg., 27, 1030, ibid., 28, 956 (1904); Canzoneri and Perciabosco, Gaz. Chim. ital., 33, 253. VEGETABLE OILS. Ill CONSTANTS. 6p. Gr. 15 C. Maumend. Elaidin. Iodine. Saponification. .022-.924 65 C. Pasty. 103-115 187-194 Adulterants. Cotton-seed, Peanut, Rape, and Poppy-seed. Cotton-seed oil would be shown by the Bechi test, Peanut oil by the low Specific Gravity and isolation of arachidic acid; Rape oil would lower all the con- stants and Poppy-seed oil raise them, especially the Iodine (138) and Maumene* (87) Values. The Baudouin test (page 76) is the characteristic test for the presence of Sesame oil. Uses. It finds application as an edible and burn- ing oil, also in tanning and soap-making. Rape-seed Oil. Per cent, of oil in seeds 33-43. Preparation. This oil, otherwise known as Colza oil, is obtained from the seeds of Brassica campestris or its varieties, colza or turnip. Properties. It is of pale yellow color, peculiar odor, and harsh taste. Composition. The glycerides of stearic, oleic, erucic, rapic and arachidic 1 acids are contained in the oil. 2 The free fatty acids vary from 0.5 to 6.2 per cent. CONSTANTS. Sp. Gr. 15 C. Maumend. Elaidin. Iodine. Saponification. .913-.917 49-64 94-106 168-178 .916 55 Pasty. 101 174 1 Archbutt, J. Soc. Chem. Ind., 17. 1009 (1898). 1 Reimer and Will, Ber., 20, 2388 (1887). 112 EXAMINATION OF CERTAIN OILS. Adulterants. Cotton-seed, Poppy-seed, Hemp- seed, Linseed, and refined Fish oil. Cotton-seed oil would be indicated by Maumene figure (76) and Bechi test; Poppy-seed oil by Iodine Value (138); Hemp-seed and Linseed by Specific Gravity (.934) and Iodine Value (176); Fish oil by the odor and high Iodine Value. Rape-seed oil is distinguished by its almost com- plete insolubility in glacial acetic acid (Valenta test) and by its high viscosity. According to Palas, 1 if colza oil be agitated with rosaniline bisulphite, a rose-red coloration is ob- tained. Other oils of this and the preceding group are unchanged, with the exception of linseed, which is changed to golden yellow. The reagent is pre- pared by mixing together in the cold thirty cubic centimeters of a one per cent, solution of fuchsin, twenty cubic centimeters sodium bisulphite, 1.31 specific gravity, two hundred cubic centimeters water, and five cubic centimeters of sulphuric acid. The test is capable of detecting two per cent, of colza oil. Uses. It is used as a lubricant and a burning oil; because of the difficulty with which it is saponified it finds little application in soap-making. Blown Rape-seed Oil. See under Blown Oils, page 127. Castor Oil. Percentage of oil in seeds 50. Preparation. Castor oil is obtained from the seeds of the castor-oil plant. 1 Analyst, 22, 45; abstr. La Nature (1897). VEGETABLE OILS. 113 Properties. It is colorless or pale greenish, of mild taste changing to harsh, especially with the Ameri- can oils. Composition. It contains the glycerides of ricin- oleic, dihydroxystearic, and stearic acids, and an active principle to which it probably owes its cathartic properties. The free fatty acids vary from 0.7 to 14 per cent. ; average about 1. CONSTANTS. Sp. Gr. 15 C. Maumend. Acetyl Value. Iodine. Saponification. .959-.96S 47 C. 150 81-90 176-186 Adulterants. Blown oils, either Linseed, Rape, or Cotton-seed, and Rosin oils. These, though but ten per cent, be present, cause a turbidity with absolute alcohol, with which castor oil is miscible in every proportion, as it is with glacial acetic acid. Rosin oil would be shown by the lowering of the saponification value. Uses. Castor oil is employed in the manufacture of Turkey red oil, for soap-making, illumination, and in medicine. According to Lane castor oil can be determined in mixtures, soaps, and Turkey-red oils by making use of the fact that the lead soaps of this oil are wholly insoluble in petroleum ether of boiling point 28-30 or 38-40 C. 1 (3) Non-Drying Oils. Almond Oil. Percentage of oil in seeds 45 to 55. J. Soc. Chem. Ind., 26, 597 (1907). 114 EXAMINATION OF CERTAIN OILS. Preparation. Almond oil is obtained from the seeds of two varieties of the almond-tree, the sweet and bitter almond, the latter yielding the more oil. Properties. It is a bland thin oil of pale yellow color, mainly pure olein with some linolein. CONSTANTS. Sp. Gr. 15 C. Maumend. Elaidin. Iodine. Saponification. .914-.920 53 C. Solid. 93-102 190 .918 97 Adulterants. It is adulterated with Peach and Apricot Kernel oils, Cotton-seed, Peanut, Lard, Olive, Sesame, and Poppy-seed oils. The first two are well-nigh impossible of detection. Cotton-seed oil would be indicated by the Maumene figure (76) and Bechi or Halphen test. Peanut oil would be shown by the isolation of arachidic acid. Lard oil by the odor when heated and by the high melting point of the fatty acid (35 C.), and also Olive by the deposition of stearin when cooled to 5. Sesame oil could be detected by the Baudouin test and Poppy-seed by the Iodine Value (138). Uses. Almond oil is used in medicine or when- ever a fairly permanent oil is required. Peanut Oil. Percentage of oil in seeds 50. Preparation. By the cold pressing of the common peanut a colorless, pleasant-tasting oil is obtained, which is used as a salad oil; a second pressing yields an oil of inferior quality, used as an edible and burning oil; a third pressing at a higher tem- perature yields a grade employed in soap-making. Properties. It varies in color from white to yellow. VEGETABLE OILS. 115 Composition. It contains the glycerides of stearic, palmitic, linolic, oleic, arachidic, and lignoceric acids. 1 CONSTANTS. Sp. Gr. 15 C. Maumend. Elaidin. Iodine. Saponification. .916-.921 45-75 C. Solid. 85-105 189-197 .917 51 98 194 Adulterants. Cotton-seed, Rape, Sesame, and Poppy-seed are used to adulterate this oil. Cotton-seed oil would be shown by the rise in the melting point of the fatty acids, those of peanut oil melting at about 28, while those from cotton-seed melt about ten degrees higher; it would further be shown by the Bechi test. Rape oil would be indi- cated by the low Saponification Value (175), Sesame oil by the Baudouin test, and Poppy-seed oil by the Specific Gravity (.924) and high Iodine Value (138). Characteristic Test. The oil can be detected in other oils by the isolation of its peculiar acid, ara- chidic acid. This is effected, according to Renard's 2 process as modified by Tolman 3 as follows : Weigh 20 grams of oil into an Erlenmeyer flask. Saponify with alcoholic potash, neutralize exactly with dilute acetic acid, using phenolphthalein as indicator, and wash into a 500 cc. flask containing a boiling mixture of 100 cc. of water and 120 cc. of a 20 per cent, lead acetate solution. Boil for a ^ossmann and Scheven, Ann., 94, 230 (1885); Kreiling, Ber. r 21, 880 (1888); Caldwell, Ann., 101. 97 (1857). 'Renard, Compt. rend., 73, 1330 (1871); also Archbutt, J. Soc. Chem. Ind., 17, 1124. 'Bull. 107, U. S. Dept. Agriculture (1907), p. 145, 116 EXAMINATION OF CERTAIN OILS. minute and then cool the precipitated soap by im- mersing the flask in water, occasionally giving it a whirling motion to cause the soap to stick to the sides of the flask. After the flask has cooled, the water and excess of lead can be poured off and the soap washed with cold water and with 90 per cent, (by volume) alcohol. Add 200 cc. of ether, cork, and allow to stand for some time until the soap is disintegrated; heat on the water-bath, using a reflux condenser, and boil for about five minutes. In the oils most of the soap will be dissolved, while in lards, which contain much stearin, part will be left undissolved. Cool the ether solution of soap to 15 or 17 C. and let it stand until all the insoluble soaps have crystallized out (about twelve hours). Filter and thoroughly wash the precipitate with ether. Wash the soaps on the filter back into the flask by means of a stream of hot water acidified with hydrochloric acid. Add an excess of dilute hydrochloric acid, partially fill the flask with hot water, and heat until fatty acids form a clear oily layer. Fill the flask with hot water, allow the fatty acids to harden and separate from the precipitated lead chlorid, wash, drain, repeat washing with hot water, and dissolve the fatty acids in 100 cc. of boiling 90 per cent, (by volume) alcohol. Cool to 15 C., shaking thoroughly to aid crystallization. From 5 to 10 per cent, of peanut oil can be detected by this method, as it effects a complete separation of the soluble acids from the insoluble, which interfere with the crystallization of the arachidic acid. Filter, VEGETABLE OILS. 117 wash the precipitate twice with 10 cc. of 90 per cent, (by volume) alcohol, and then with alcohol 70 per cent, by volume. Dissolve off the filter with boiling absolute alcohol, evaporate to dryness in a weighed dish, dry and weigh. Add to this weight 0.0025 gram for each 10 cc. of 90 per cent, alcohol used in the crystallization and washing if done at 15 C. ; if done at 20 add 0.0045 gram for each 10 cc. The melting point of arachidic acid thus obtained is between 71 and 72 C. Twenty times the weight of arachidic acid will give the approximate amount of peanut oil present. No examination for adulter- ants in olive oil is complete without making the test for peanut oil. Arachidic acid has a characteristic structure and can be detected by the microscope. Uses. These have been already given under the preparation. Olive Oil. Percentage of oil in the fruit 40 to 60. Preparation. Olive oil is prepared by expressing or extracting the fruit of the olive-tree; the oil varies greatly according to the tree, there being no less than three hundred varieties in Italy alone, and also the degree of ripeness and manner of gathering of the fruit itself. Properties. It varies in color from almost color- less to golden yellow or green. Composition. It contains palmitin, stearin, olein, and linolin, 1 the solid glycerides constituting about twenty-eight per cent, of the oil. 1 Ilazura and Griissner. 118 EXAMINATION OF CERTAIN OILS. The free fatty acids vary from 1 to 24 per cent. According to Allen, an oil containing more than five per cent, of free fatty acids is unfit for a lubri- cant, as it attacks the metals, and also, according to Archbutt, as a burning oil, as it causes charring of the wick. CONSTANTS. Sp. Gr. 15 C. Maumend. Elaidin. Iodine. Saponification. .914-.918 41-47C. Very solid. 78.2-91.5 185-203 .916 35 82 190 Adulterants. Cotton-seed, Peanut, Rape, Sesame, Poppy-seed, and Lard. Cotton-seed oil would be shown by the Bechi test and the high Maumen figure (76) and Iodine Value (108). Peanut oil by isolation of Arachidic Acid and high Iodine Value (98). Rape oil would be indi- cated by the Saponification Value (175) and Iodine Value (101). Sesame oil by the Baudouin test. Poppy-seed oil by the Iodine Value (138) and Mau- men6 figure (87). Olive oil is characterized by the low Maumene* and Iodine Values and by the solid elaidin. Uses. It is used as an edible oil, for oiling tex- tiles, as a soap stock, and as a burning oil. ROSIN OILS AND TURPENTINE. Rosin Oil. Rosin oil is prepared by the distilla- tion of common rosin (colophony) in stills holding about thirty barrels. About eighty-five per cent, of rosin oil and three per cent, of rosin spirits, or pino- VEGETABLE OILS. 119 line, are obtained. Acid water, gas, coke, and losses account for the remaining twelve per cent. The product obtained is a thick oil, known as "First Run;" this is redistilled, yielding a darker-colored oil, called "Second Run." This operation is re- peated, yielding "Third," " Fourth," and even " Fifth Run." The oil in the market is, however, 1 in nearly every case the product of a single distillation; upon dis- tilling five to six thousand pounds of rosin the fol- owing yields are obtained. Water 0.5 to 1 per cent. Naphtha 1.5 to 2 per cent. Raw oil] 84 to 88 per cent. Pitch 3 to 5 per cent. Gases, loss, etc. 6 to 8 per cent. CONSTANTS. Sp. Gr. Iodine. Free Acid. 975-.995 112-115 .05-4.8 per cent. PROPERTIES OF ROSIN OILS. ROSIN OIL, SECOND RUN. Sp. Gr. at 15. Maumene". Iodine. Saponification. .987 32 59 34 Free acid, 12.6. ROSIN OIL, THIRD RUN. Sp. Gr. at 15. Maumene". Iodine. Saponification. .985 34.0 77 25 Free acid, 13.7. ROSIN OIL, FOURTH RUN. Sp. Gr. at 15. Maumene*. Iodine. Saponification. .981 32.5 23 20 Free acid, 9.6. 1 Spayd, Chem. Eng'r, 3, 218 (1905). 120 EXAMINATION OF CERTAIN OILS. Deodorized Rosin oil is that portion of the later runs which is freed from the " spirits" by fractional distillation. Uses. " First Run" is employed in making axle grease, in oiling leather, and making cements. " Second Run" finds use in printing ink and in the leather industry. " Third" and "Fourth" runs are used mainly for mixing with other oils. Qualitative Test. Rosin oil may be detected by the Liebermann-Storch reaction. 1 One to two cubic centimeters of the oil are shaken with an equal quan- tity of acetic anhydride and gently warmed. When cool, the acetic anhydride is pipetted off and tested by the addition of one drop of concentrated sulphuric acid. A fine violet color is produced in the presence of rosin oil. Cholesterol which is contained in the animal fats produces a similar coloration; this can be removed by saponifying the oil as completely as possible and shaking out the somewhat dilute soap solution with ether or petroleum ether. The soap solution is then acidified, setting free the fatty acids, and these treated with acetic anhydride as if they were the oil. Renard's test modified by Allen 2 consists in add- ing a few drops of stannic bromide, dissolved in carbon bisulphide, to a few drops of the oil, also dissolved in carbon bisulphide. Should rosin oil be present a violet color will be produced, which on 1 Storch, J. Soc. Chem. Ind., 7, 136 (1888). 'Commercial Organic Analysis, ii. 463. VEGETABLE OILS. 121 standing forms a deposit at the bottom of the tube. Glacial acetic acid is recommended as a solvent in the case of mineral oils, these not dissolving it to any appreciable extent and not masking the reaction. Wiederhold l states that rosin oils are dissolved at 15 C. by half their volume of anhydrous acetone, while mineral oils, especially American, are almost unacted upon by it. Rosin Spirits. Its preparation has already been given under rosin oils. Properties and Composition. It has a peculiar odor and contains heptine, 2 C 7 H 12 , which boils at 103-104 C. and absorbs oxygen readily. CONSTANTS. Sp. Gr. 15 C. Maumend. Iodine. .856-.8S3 91 C. 185 The boiling point varies frorh 80 to 250 C. The free acid is sometimes 15 per cent. Valenta 3 states that rosin spirits, or " essence of turpentine" as he calls it, can be distinguished by the following reactions: (1) acetic anhydride and one drop of sulphuric acid give an intense green color; (2) one part of oil and 1 to 2 parts of a 6 per cent, solution of iodine in chloroform or carbon tetrachloride, warmed gently on a water-bath, give intense green to olive-green colors. The strongest colors are given by the lower boiling fractions. 1 Z. anal. Chem., 33, 111 (1894). 1 Veitch, Bureau of Chemistry Circular No. 36, p. 31 (1907). 3 Chem. Zeit., 29, 807 (1905); abstr. Analyst, 30, 342. 122 EXAMINATION OF CERTAIN OILS. This last reaction is not given by oil of turpentine (gum), pine resin oils (wood turpentine), light petro- leum, oil of camphor, or rosin oil. Adulterants. Petroleum and shale products. Uses. As a substitute for gum turpentine. Turpentine. Preparation. Turpentine is pre- pared 1 by distilling pine resin in copper stills of about eight hundred gallons' capacity; the process requires some care to prevent overheating and obtain a fine quality of rosin. To aid the process, after the crude resin is melted, a stream of tepid water from the condenser is run into the still, thus making a distillation with steam. The yield and quality vary according to the length of time the trees have been producing resin, both growing inferior with age. The crude resin, or "dippings," of the first season is called "virgin dip," and produces the finest quality of rosin, W. W. (water white) and W. G. (window glass); the better grades are N, M, and K, passing through the poorer grades to the black A. From two hundred and twenty-five barrels of soft turpen- tine and one hundred and twenty barrels of hard gum, the product of a second season, nineteen hun- dred gallons of turpentine and two hundred barrels of amber rosin, I, H, or G, were produced. The resin is chiefly obtained from the Long-leaf Pine, Pinus palustris or australiSj known also as Southern, Yellow, or Hard Pine. 1 Condensed from a monograph on " The Timber Pines of the Southern United States," by Filibert Roth, U. S. Dept. of Agri- culture (1896). VEGETABLE OILS. 123 Properties and Composition. Turpentine is a colorless liquid of peculiar taste and odor. On exposure to the air it absorbs oxygen and gradually becomes resinous. It consists mainly of a hydro- carbon, Pinene, C 10 H 16 . CONSTANTS. Sp. Gr. 15 C. Iodine. .8G2-.87 331, 1 384-391 3 The boiling point is 155 to 156 C., and eighty- five per cent, should pass over between 155 and 163, the remainder below 183 . 3 The flash point is 83 to 95 F. by the New York State Board of Health tester. American turpentine deflects polar- ized light to the right, although a sample obtained from spruce-trees had a specific rotation of 40.79. 4 Adulterants. Petroleum and Shale Products, Rosin Spirits, Wood, 5 and Russian Turpentine are the chief adulterations. Petroleum and Shale Products: the lighter ones would be indicated by the lowering of the specific gravity, flash test, and iodine value, they having a value of 30 and 70 respectively, and by distillation. Kerosene might be detected by the "bloom." To determine the quantity of petroleum or heavy oil added, Vulpius 6 floats a gram of the suspected 1 Wilson, Chem. Trade J., 6, 316 ; J. Soc. Chem. Ind., 9, 657 (1890). 'Worstall, ibid., 23, 302 (1904). Long, ibid., 10, 261; J. Soc. Chem. Ind., 11, 549. (1892). 4 Long, J. Am. Chem. Soc., 16, 884 (1894). 8 McCandless, ibid., 26, 981 (1904). Apoth. Ztg., 6, 289 ; abstr. J. Soc. Chem. Ind., 10, 800 (1891). 124 EXAMINATION OF CERTAIN OILS. sample and of a pure sample each in a separate watch-glass upon a beaker of water kept at 80. When the pure sample has evaporated, both are weighed, the residue from the pure sample deducted from the other, and this difference represents the heavy oil added. According to Burton, 1 the oxida- tion with fuming nitric acid gives fairly quantitative results on the percentage of petroleum products present. This is effected by dropping slowly one hundred cubic centimeters of the sample into three hundred cubic centimeters of fuming nitric acid in a flask immersed' in cold water; the oxidation products are dissolved in hot water and the petro- leum remains. Rosin Spirits could be detected by distillation and treatment of the residue with stannic bromide (Renard's test, p. 120) dissolved in carbon bisul- phide and also Valenta's test, p. 50. The addition of rosin spirits or wood turpentine is readily shown by Herzfeld's test, the production of a yellow color by shaking with a solution of sulphurous acid. They would also cause a lowering of the iodine value, that for rosin spirits being 185 * and refined wood turpentine 212. 2 McCandless 3 claims to detect the latter by distil- ling the turpentine according to Engler's method for kerosene, p. 20, and determining the refraction index of various distillates. "The flame used must 1 Am. Chem. J., 12, 102. 'Worstall, loc. cit. 3 Loc. cit. VEGETABLE OILS. 125 be small, the thermometer rise very slowly, and the first half cubic centimeter of the distillate collected by itself, the refractive index being taken at 25 C. In case of no genuine oil will this fall below 1.4659, being usually 1.4665 to 1.4678. Sev- eral samples of wood turpentine show readings as low as 1.4652, 1.4646, or even 1.4639. When the wood turpentines do not show a low initial reading, they nearly always show a high reading on the final portion of the distillate. I have adopted the 97th and 98th cc. as being in practice the most convenient to collect separately for the purpose of making the final refractive index. In the case of the genuine (gum) spirits this reading will not exceed 1.4765, usually much less, but with wood turpentine will exceed 1.4765 and may even reach 1.4840. A further distinction between genuine and wood turpentine may be observed during this distillation; in nearly all genuine spirits 95 per cent, will have distilled over by the time the temperature reaches 165 C., whereas with wood turpentine, when 95 per cent, have come over, the thermometer is much higher than 165 ." Paul 1 says the above method is fairly satisfactory. Besides this method Geer 2 recommends the frac- tional distillation with steam. Russian Turpentine would be shown by the higher temperature of distillation, 170 to 180. Pure tur- 1 J. Ind. and Eng. Chem. 1, 27 (1909). 2 U. S. Dept. Agriculture Forest Service Circular 153 (1908). 126 EXAMINATION OF CERTAIN OILS. pentine should leave no residue upon writing-paper after half an hour. Uses. Turpentine finds extended use as a sol- vent for fats, waxes, resins, and rubber, and as a "drier" in paints. Wood Turpentine. Wood Spirits, Stump Ter- pentine. As its name denotes, this is obtained by distilling pine wood (" light wood," stumps, knots, etc.) with steam: superheated steam was formerly employed, but modern practice uses direct steam, postponing destructive distillation or any other process until the spirits are first removed. The wood is chipped as for the manufacture of wood pulp, filled into horizontal or vertical retorts, and steam blown into them: this requires from one to twelve hours and the yield is from 6 to 25 gallons per cord, the average being 12 to 15 gallons. When the stills are properly operated and the product is suitably refined, there should be prac- tically no difference between the turpentine pre- pared in this way and the ordinary (gum) tur- pentine. 1 Properties. It has a specific gravity of 0.860 to .880 at 20 C., and 95 per cent, should distil between 150 and 185 C. 2 and an iodine number of 212 to 352. 3 Adulterants and Uses. The same as for gum turpentine, which see. On account of the odor of 1 Teeple, J. Soc. Chem. Ind., 26, 811 (1907). 'Veitch, loc. cit., p. 29. 3 McCandless, loc. cit. VEGETABLE OILS. 127 some varieties it is better used for out-door paint- ing than for inside work. Varieties of Turpentine and Sources. American turpentine, from Pinus palustris or australis, the Longleaf Pine, dextrorotary. English turpentine, from gum collected in Amer- ica, from P. australis and P. tceda, Loblolly. French, from Pinus maritima, Sea-pine, and P. glabra, Spruce Pine, laevorotary. German, from P. sylvestris, Scotch Pine or Fir, P. nigra, Black Pine, and P. rotundata. Venice, from Larix europcea, Larch. Russian, from P. sylvestris, and P. ledebourii, dextrorotary. Blown Oils. Preparation. Blown, Base, Thick- ened, or Oxidized oil is usually prepared by heat- ing the oil to 70 or 110 in a jacketed kettle and forcing a current of air through it; after the action is once started no further heating is usually necessary. Properties. The color of the oil darkens slightly and the density and viscosity are much increased. Benedikt and Ulzer think that the fatty acids are oxidized to hydroxyacids. The oils submitted to this process are chiefly Rape and Cotton-seed, although it is often applied to Linseed, Sperm, and Seal oils. CONSTANTS. 1 Sp. Gr. 15 C. .967 .974 Maumend. 2 253-(57) 227 Iodine. 63.6 56.4 Saponification. 197.7 Rape. 213.3 Cotton-seed. .980 ... 90.7 208.6 Maize. 1 Thomson and Ballantyne, J. Soc. Chem. Ind., 1 1, 506 (1892). 3 Specific temperature reaction. 128 EXAMINATION OF CERTAIN OILS. Uses. On account of their high viscosity, blown oils are used to mix with other oils for lubricating purposes. Palm Oil. Preparation. Palm oil is obtained from the flesh or pericarp of the palm-nut; this grows in immense quantities on the west coast of Africa. The fruits are fermented, whereby the oil rises to the top, or it is expressed from the fresh fruit. The latter process yields the finer and more fluid product. Properties. Owing to its method of preparation its properties are quite varied. It is of a buttery or tallowy consistency, of orange-yellow to dirty red in color, and has an odor in some samples recalling that of violets. By heating to a high temperature or treatment with acids it may be bleached. Composition. It is mainly palmitin, with some olein and free palmitic acid. CONSTANTS. Sp. Gr. 99 C. Iodine. Saponification. .859 53-56 196-202 Adulterants. Water and dirt, mostly sand. Characteristic Tests. 1 Dissolve 100 cc. of the oil in 300 cc. petroleum ether and shake with 50 cc. 0.5 per cent, potassium hydrate. The aqueous layer is drawn off, acidified with hydro- chloric acid, and shaken with 10 cc. carbon tetra- chloride: a portion of this solution is treated in a 1 Crampton and Simons, J. Am. Chem. Soc., 27, 272 (1905). VEGETABLE OILS. 129 porcelain crucible with 2 cc. of a mixture of one part crystallized phenol with two parts carbon tetrachloride. Five drops hydrobromic acid (sp. gr. 1.19) are added and the contents mixed by gently agitating the crucibles. The almost immediate development of a bluish-green color is indicative of palm oil. Ten cubic centimeters of the oil are shaken with an equal volume of acetic anhydride, then one drop sulphuric acid (sp. gr. 1.53) is added and the mixture shaken a few seconds. If palm oil be present the lower layers on settling out will be found to be colored blue with a tint of green. 1 Uses. For the manufacture of soap and candles and coloring other oils. Cocoanut Oil. Preparation. Cokernut oil is ob- tained from the fat of the cocoanut, the fruit of a species of palm. The finest quality is that prepared in Cochin (Malabar) from the fresh fruit. Infe- rior varieties are made from the dried kernels, or "coprah," which contain 60 to 70 per cent, of oil. Properties. It is a solid white fat of bland taste and peculiar odor, readily turning rancid. It is soluble in two volumes of absolute alcohol at 31 C. Composition. It contains a larger proportion of volatile acids than most oils; the glycerides of caproic, caprylic, capric, oleic, lauric, and myristic acids are among those present. 1 This test would seem open to question. 130 EXAMINATION OF CERTAIN OILS. CONSTANTS. Sp. Gr. 99 C. Iodine. Saponification. .874 8-10 253-268 Adulterants. It is rarely adulterated. Characteristic Test. Hanus 1 has devised a method for the detection of this fat in other fats and oils based upon the volatility of the ethyl esters made from the acid in cokernut oil, the " ethyl ester num- ber." The procedure is as follows: five grams of the melted fat are weighed into a 200 cc. Erlen- meyer flask, and heated for fifteen minutes in an oven at 50 C.; exactly 30 cc. of -^ alcoholic potas- sium hydroxide solution are then added from a burette, and the mixture is thoroughly shaken until perfectly clear, usually about two minutes. After keeping the contents of the flask at a tem- perature of 50 C. for eight minutes, 2 cc. of dilute sulphuric acid are added, the acid being of such concentration that the 2 cc. will exactly neutralize the 30 cc. of potassium hydroxide solution. The contents of the flask are now diluted to a volume of 145 cc. with water, a few pieces of quenched pumice are added, and the mixture is distilled, using a fusible metal bath and single bulb tower. The first 30 cc. of alcoholic distillate which comes over is collected in a graduated cylinder, the next 100 cc. of distillate being received separately in a 100 cc. flask. The whole distillation must not take longer than twenty-five minutes. Both frac- 1 Hanus, Z. Nahr. und Genussm., 13, 18 (1907), 16, 577 (1908). VEGETABLE OILS. 131 tions of the distillate are now transferred to two separate flasks; alcohol is added to the aqueous distillate until a clear solution is obtained, the free acidity of both portions is neutralized, using phenolphthalein as an indicator, and they are then boiled with 40 cc. of alcoholic potassium hydrox- ide solution. After titrating back the excess of alkali, the number of cc. of & alkali required for the saponification of the esters from 5 grams of the fat is calculated from the f used. For cokernut oil the number of cubic centimeters of ^ alkali required for the saponification of the esters in the alcoholic portion is from 38 to 44, butter 8-9.4, lard 1.6. Palm oil, 23.1. Cocoa butter 1.3-1.6. Uses. It is used in soap-making (marine soaps), in candle-making, and as an edible fat. CHAPTER VII. ANIMAL OILS. (1) Marine Animal Oils. a. Fish Oils. Menhaden Oil. This oil is otherwise known as mossbunker, pogy, porgy, or whitefish oil. Preparation. It is prepared from the menhaden by steaming and expression. There are several grades in the market, differing in appearance ac- cording to the source from which they are derived. They are Select Light Strained, Select Light, Choice Brown, Dark, and Gurry oil. The better varieties are obtained by gentle pressure and subsequent bleach- ing, and the others by the pressing of the residues. Properties. It is yellow to brown in color, and oxidizes readily on exposure to the air. It is to be noted, however, that the firm, hard coating or "skin" which is formed on drying is usually not as closely adherent to the surface be- neath it as that formed with linseed oil. Composition. It apparently contains the glycer- ides of linoleic, myristic, asellic, and acetic acids, and also isocholesterol. CONSTANTS. 8p. Gr. 15 C. Maumend. Elaidin. Iodine. Saponification. .927-.93S 123-128C. Liquid. 139-172 189-192 .930 126 154 190 132 ANIMAL OILS. 133 Adulterants. The chief adulterant is Mineral oil, which would be shown by a lowering of all these constants. Uses. It is used in currying, for adulterating other oils, as linseed, whale, and sardine, as a sub- stitute for linseed oil, and as a burning oil for mines. REFERENCE. G. B. GOODE, " The Natural and Economic History of the Ameri- can Menhaden," U. S. Commission of Fish and Fisheries, vol. v., 1879. /?. Liver Oils. Cod Oil. Three varieties of cod or cod-liver oil are obtainable in the market, the pale yellow, or " steam rendered," and the light brown, both of which are used in pharmacy, and for the examina- tion of which recourse must be had to larger works. The other, the brown oil or "cod oil,' 7 used in curry- ing, may be derived from the liver of any fish, hence it is impossible to give any data upon which judg- ment may be formed. T. Blubber Oils. Whale Oil. Preparation. Whale or Train oil is obtained by rendering the blubber of various species of whales except the sperm and bottlenose. Properties and Composition. It has a strong fishy odor, a "nutty" taste, and is of a light-yellow to yellowish-brown color. Little is known regard- ing its constitution. As may be expected, its com- position varies widely. 134 EXAMINATION OF CERTAIN OILS. CONSTANTS. Sp.Gr. 15 C. Maumene". Iodine. Saponification. .917-.930 85-91C. 110-136 188-193 .927 88 120 190 Adulterant. It is largely adulterated with Seal oil, which there is little chance of detecting. Uses. Whale oil is used as a leather dressing, as a burning oil, and to mix with other oils as a lubricant. (2) Terrestrial Animal Oils. Neat's-foot Oil Preparation. Neat's-foot oil is obtained from the feet of neat cattle. The hoofs are separated, the bones of the foot disjointed, and the latter boiled with water, the emulsion allowed to settle, and the oil which rises separated. As is the case with all oils, that which is obtained by the least degree of heat or pressure is the best. Properties. It is of a light-yellow color, bland taste, possesses a peculiar odor, and little tendency to turn rancid. Composition. It is nearly pure olein, containing a small quantity of stearin, which it frequently deposits. The free fatty acids may amount to six per cent. CONSTANTS. Sp. Gr. 15 C. Maumene*. Elaidin. Iodine. Saponification. .914-.916 42-49.5 C. Solid at times. 66-76 194-199 If the iodine number be less than 63, it probably contains hide oil. The fatty acid should be less than one per cent. Titer test may be from 17 to 26. Adulterants. Fish, Poppy-seed, Rape, Cotton- seed, Mineral oils, and other hoof oils. ANIMAL OILS. 135 Fish oil would be shown by the Iodine Value and Maumene test, also by the odor when heated; Poppy-seed oil by the Gravity (.925) and Iodine Value (138); Rape oil by Saponification (175) and Iodine Value (101); Cotton-seed by the Bechi test and Iodine Value (108); Mineral oil by the lower- ing of all the constants given. Uses. Neat's-foot oil finds application as a lubri- cant, either by itself or mixed with other oils, and for currying purposes. Horse Oil Horse oil is prepared by rendering dead horses. CONSTANTS. Sp. Gr. 15 C. Maumend. Iodine. Saponification. .916-.922 46-55C. 75-86 197.1 It is used for mixing with and adulterating other oils, as, for example, neat's-foot; when refined it has been used to adulterate olive oil. Lard Oil. Preparation. Lard oil is obtained by pressing lard; upright screw-presses are used and a pressure of about eight thousand pounds to the square inch employed; from forty to sixty per cent, of the lard is obtained as oil. Brands. These vary according to the source whence they are derived; the various lards in the American market are: Neutral Lard, obtained from the "leaf" by rendering at a low temperature (105 to 120 F.), used in making butterine. Only a portion of the fat is thus extracted; the operation is then completed, yielding Leaf Lard. Choice Lard is obtained from some parts of the leaf and fat from 136 EXAMINATION OF CERTAIN OILS. the backs. Prime Steam Lard is the product ob- tained from the trimmings, head, heart, and some intestinal fat. Gut Grease is obtained by rendering all the other parts of the hog except the heart, liver, and lungs. 1 Besides these products obtained from the live hog, there are Butchers 1 Lard or Crackling Grease, obtained from scraps and trimmings, and White Grease and Brown Grease, which are obtained from hogs dying in transit, being prepared from the eviscerated animal and its viscera respectively. Lastly, there is Yellow Grease, a product of the refuse of the packing-houses. All but the first two lards are pressed, yielding an oil which is classed according to its color as "Prime" (very light straw) to "No. 2" (brown). The varieties in the market are as follows: "Prime" Lard oil, prepared from Prime Steam Lard; "Pure" Lard oil, from No. 1 Lard and White Grease; "Extra No. 1," from Light Yellow Grease; "No. 1," from Yellow Grease; "No. 2," from Brown and Gut Grease; and "Crackling Oil," from Crackling Grease. Properties. The color varies from very light straw to brown, and the odor from almost none to offensive in the No. 2 lards. Composition. Its chemical composition is largely olein, with admixture of stearin and palmitin. 1 Condensed from "Lard and Lard Adulterations," by H. W. Wiley, U. S. Dep't Agriculture, Bull. 13, 1889, p. 14. ANIMAL OILS. 13? CONSTANTS. Sp .Gr. 15 C. Maumene 1 . Elaidin. Iodine. Saponification. .914-.916 39 C. Solid cake. 60 195-6. 1 41 72.5 2 43 75 3 Various parts of the animal give oils which vary considerably; the iodine values of oils from different sources are as follows: 4 Leaf. Intestine. Back. Foot. Head. 52.5-53 57.3 60.6 77.3 85 Adulterants. These are Cotton-seed, Corn, and Neutral Petroleum oils. Cotton-seed oil would be shown by the Elaidin, Maumene, and Bechi tests. Corn oil would be in- dicated by the Maumene test (58) and Iodine num- ber (115). Petroleum by the flash test and lowering of the constants. Uses. Lard oil is used as a burning and lubri- cating oil, as an edible oil, and for oiling textile material preparatory to spinning. REFERENCE. WESSON, Jour. Am. Chem. Soc., 17, 723-735 (1895). Tallow Oil. Preparation. Tallow oil is prepared by pressing tallow after the manner of lard, which see. Properties. It is a light-yellow bland oil, and of an odor resembling tallow. CONSTANTS. Sp. Gr. 15 C. Maumene*. Elaidin. Iodine. Saponification. .916 35 Solid cake. 56 197 1 No. 2 lard. No. 1 lard. ' Prime lard. 4 Wiley, toe. cU. 138 EXAMINATION OF CERTAIN OILS. Uses. It is used to mix with other oils and as a lubricant. Elain or Red Oil. Preparation. Elain oil, or, as it is sometimes called, " Saponified Red oil," is obtained by the saponification of the solid fats by the lime, sulphuric acid, or water methods. The fatty acids thus freed from their combination with glycerin are allowed to solidify and are pressed. According to the temperature, more or less stearic and palmitic acids go into the product; these can be separated by distillation. It is oftentimes semi-solid, resembling tallow; the distilled varieties are light brown to deep red. Composition. Chemically speaking, it is nearly pure oleic acid. CONSTANTS. 1 Sp. Gr. 15 C. Free Fatty Acids. Iodine. Saponification. .899-.908 80-97 90 2 200 It may contain some unsaponifiable matter, con- sisting of hydrocarbons formed in the process of distillation; these may vary from three to seven per cent. Uses. It is used for oiling wool, as it readily saponifies, and in soap-making. 1 Allen, Lewkowitsch. * Iodine number of the pure acid. B. WAXES. LIQUID WAXES. Sperm Oil Preparation. The real sperm oil is obtained from the great cavity in the head of the sperm whale; it is often mixed with the oil obtained from the body, or " blubber oil." The process of manufacture consists in chilling the crude oil, sepa- rating the spermaceti by pressure, and bleaching the expressed oil in thin layers by exposure to the sun. Properties. It is a limpid, pale-yellow oil of faint odor and taste. Composition. It contains no glycerides (Allen, Lewkowitsch), but is a mono-ester, a compound of an alcohol 1 and an organic acid. 1 When saponified these alcohols are freed, and the oil yields forty per cent, of unsaponifiable matter. It may con- tain two per cent, of free fatty acids. CONSTANTS. Sp. Gr. 15 C. Maumen<*. Elaidin. Iodine. Saponification. .844-.S84 45-47C. Solid at times. 81-90 123-147 .880 (70) Adulterants. Owing to its high cost it is often adulterated, Whale, Mineral, Rape, Liver, and 1 Cetyl alcohol, C ie HJJ OH, and palmitic acid have been identified in the oil. 139 OF THE UNIVERSITY 140 EXAMINATION OF CERTAIN OILS. Arctic Sperm (bottlenose whale) oil being used for this purpose. Whale oil would be shown by the strong fishy odor and " nutty" taste, also by the raising of all the constants. Mineral oils would be indicated by the low flash point, corresponding to a gravity of 0.880, and by the lowering of the constants. Rape oil by the high Saponification Value (175) and the isolation of the glycerin, which when multiplied by ten gives the fatty oils. Liver oils would be revealed by the violet coloration with sulphuric acid and rise in the constants. Arctic Sperm oil might be shown by the taste. Uses. It is employed as a lubricant; the viscosity is less than any other non-drying fatty oil, and also varies less than any other oil with increase of temperature. REFERENCES. STABBUCK, "History of American Whale Fishery from Earliest Inception to 1875." Report of U. S. Commissioner of Fisheries, vol. iv., 1875. SCAMMON, "Mammalia of North- Western America." CHAPTER VIII. RECOVERED AND WASTE OILS AND FATS. THESE have assumed more importance of late in this country, particularly with the increasing requirements of boards of health that these sub- stances be kept out of the brooks and rivers. Some of them are : Wool Fat, Fuller's Grease, Distilled Grease Oleines, Black Oil, Sod Oil, Garbage Grease. Cotton-seed Foots, Wool Fat British, German, or American Degras; Suint; Lanoline; Wool, Recovered, or Yorkshire Grease. Preparation. As the names denote, this is the greasy material obtained in the washing of wool: 1 wool contains from 30 to 80 per cent, of impurities, made up of (a) wool grease, the fatty matter secreted by the skin of the sheep, amounting to 6 to 17 per cent, of the wool; (b) suint, also a skin secretion but soluble in water, consisting of the potassium salts of oleic, valeric, and acetic acids, with sul- phates, phosphates, chlorides, and nitrogenous com- pounds amounting to 5 to 24 per cent, of the wool; 1 For a detailed description of wool- washing, see Thorp's "Out- lines of Industrial Chemistry." 141 142 EXAMINATION OF CERTAIN OILS. and (c) dirt, earthy matter, and manure. These are removed in two ways, by scouring with soap and alkali, and by extraction of the grease with solvents, usually naphtha or carbon tetrachloride, and subsequent washing. These foul and ill-smell- ing wash-waters are usually run into the streams and form one of the most troublesome sources of pollution. Wool grease is difficultly saponifiable but readily emulsifiable and is deposited the entire length of the stream. To recover the grease, the wash-waters are allowed to stand, to settle out the sand and dirt, then "soured" with sulphuric acid, whereupon part of the grease floats and part settles; these portions are collected and pressed hot through canvas. The grease thus obtained contains besides wool grease, the fatty acids of the soaps used and also traces of sulphuric acid. Or the solvent is distilled off from the solution of the grease and the latter strained into barrels. The product thus obtained is of lighter color and better quality than that ob- tained in the acid process, is free from sulphuric acid and practically so from fatty acids, and is the only one to which the term wool grease is properly applied. Properties. It is a light or dark brown substance of peculiar, unpleasant odor and salvy consistence; it is not wholly saponified by alcoholic potash, re- quiring sodium alcoholate to complete the process. It mixes with water readily and forms emulsions which are unusually permanent, particularly if any WASTE FATS. 143 alkali be present, and which may contain as much as 80 per cent, of water. It is not readily oxidized on exposure to the air. Composition. It is a complex mixture of al- cohols and esters, a collection of waxes and not a fat: the esters are largely those of cholesterol and its isomers. Lanoceric, lanopalmic, myristic, car- naubic, and other oily and volatile acids, ceryl and carnaubyl, alcohol, cholesterol, and isocholesterol are some of the compounds which have been found in the grease. CONSTANTS. From what has been said, it will be seen that it is impossible to give any figures to which the name constant can properly be applied. Sp. Gr. Iodine. Saponification. ~^ 0.9017 26 98-102 lo. o ANALYSIS OF WOOL GREASE IN PER CENT. Water. Fatty acids. Neutral oil. Unsaponifiable. 1 19-26 68-17 12-56 Adulterants. It is rarely adulterated, the usual one being mineral oil, not intentionally added but coming from the wash-waters. It could be detected by its resistance to saponification and insolubility in acetic anhydride, which converts the cholesterol into the acetate. Rosin oil might also be used and could be detected by partial saponification with potash, the object being to saponify the rosin acids in the oil and not the cholesterol esters, and the liberation of the rosin acids, which are submitted to the Liebermann-Storch test. 144 EXAMINATION OF CERTAIN OILS. Uses. Degras is used to mix with oils for curry- ing purposes, with lard and similar oils for "wool oils," and when purified forms the Lanoline of the Pharmacopoeia. This, from the ease with which it is absorbed by the skin, makes an admirable basis for salves and ointments. There are two varieties, one anhydrous (adeps lanse), and one with about 25 per cent, of water or Lanoline proper. It is used to replace tallow in certain cylinder oils. Distilled Grease. Preparation. This is prepared by distilling wool grease in cast-iron stills, using superheated steam to carry forward the heavy vapors. A "stearine" and "oleine" are obtained by cooling and pressing the distillate. Wool fat pitch is left in the retort. Properties. The crude stearines are brownish and, like all these products, of a peculiar penetrat- ing aldehydic odor; they are refined and are then white and crystalline. The oleines are light yellow to dark brown and have a greenish fluorescence, which must not be mistaken for the bluish " bloom" of the mineral oils used as adulterants. Composition. The esters originally present in the wool fat are broken down into hydrocarbons and fatty acids of high molecular weight, stearic, pal- mitic, and oleic, which in turn are dissociated into acids of lower molecular weight and other hydro- carbons. The following equation, cited by Smith, 1 gives an idea of what may have taken place: 1 Ann. China. Phys. (3), 6, 40. WASTE FATS. 145 l Cetyl palmitate = Palmitic acid+Cetene The nature of these hydrocarbons is not well understood; it is, however, probable that they can be distinguished from hydrocarbons intentionally added by the determination of the bromine addi- tion and substitution numbers, the optical rotation, and index of refraction. These constants, obtained on hydrocarbons separated from some distilled grease oleines by Gill and Mason, 1 are shown in the table below. Refractive Oleine. Bromine. Optical Index Sp. Gr. Addition. Substitution. Rotation, at 20 C. A 0.896 28.8 14.2 +17 58' 1.4967 BPure 0.902 25.1 14.8 1736' 1.4991 C 0.896 21.5 16.8 15 13' 1.4948 D (doubtful purity) 3.8 9.0 2 56' 1.4921 Mineral oils .. . . J- 848 to 4 ' 4 to 5 ' 6 to l25' L4662 to 10.863 5.9 8.4 1.4750 The extraction of the unsaponifiable matter is carried out as follows: 200 grams of the oil are saponified by boiling on a water-bath two or three hours with an excess of alcoholic potash (120 grams to the liter) in a 750 cc. flask, provided with a re- turn flow condenser. When the saponification is complete the solution is transferred to a liter sep- aratory funnel and shaken several times with 300 to 400 cc. of redistilled gasolene (86 Be*). The soap solution is thrown away. The gasolene solu- tion is concentrated to about one-half its volume 1 J. Am. Chem. Soc., 26, 665 (1904). 10 146 EXAMINATION OF CERTAIN OILS. and washed with warm water mixed with a little alcohol in the separatory funnel until all the soap is removed. The remainder of the gasolene is dis- tilled off in the water-bath, and the residue heated to 130 C. in a porcelain dish to drive off the water and last traces of gasolene. From the saponification numbers of the dif- ferent oils, the requisite amount of alcoholic pot- ash is calculated, and 100 per cent, excess em- ployed. After the saponification, when gasolene was first added and the mixture thoroughly shaken, no separation into two layers occurred, even after several hours' standing. Salt was added, but with- out effect. Finally water was added in small quan- tities until two distinct layers formed. In washing the gasolene solution water alone was tried, but did not appreciably dissolve the soap. When warm water, mixed with a little alcohol, was used the soap dissolved readily. In heating the oil to 130 C. to drive off water, a very small flame or, better, an electric stove should be used, and the oil constantly stirred to prevent bumping. A thermometer serves well as a stirring rod. The unsaponifiable oil is freed from cholesterol and other higher alcohols by boiling for an hour with 100 cc. of acetic anhydride in a flask provided with a return flow condenser, and heated over a sand-bath. Water is added, and the solution transferred to a separatory funnel, where it is washed with water and alcohol until the upper layer is clear and no odor of acetic acid is perceptible. The cho- WASTE FATS. 147 lesterol and higher alcohols are dissolved by the acetic anhydride, leaving the hydrocarbons. After submitting the oils to this process, a deter- mination of their saponification number is made, and if more than 0.2 cc. of alcoholic potash is used up, the treatment with alcoholic potash and acetic anhydride repeated. The examination of distilled wool grease is con- ducted upon the same general lines as indicated in the case of wool fat. Lewkowitsch 1 obtained the following results : Free fatty acids 54.9 per cent. Combined fatty acids, glycerides 7.0 " " Unsaponifiable matter 38.8 " " Some distilled grease oleines analyzed by the author showed the following composition: Free fatty acids (oleic) 37% 47% 52% 37% Glycerides 33% 3% 18% 18% Unsaponifiable matter 30% 51% 30% 45% Flash point, F 364 360 370 346 Adulterants. The only adulterant is mineral oil, the detection of which has already been given. Uses. Distilled grease stearine is used in soap and candle making; the oleine is used as a " wool oil. " Sod Oil, Moellon, French Degras. This is an oil obtained as a by-product in the process of currying leather, or specially prepared. Preparation. The skins after being dehaired are well rubbed with fish oil, either "cod," whale, 1 J. Soc. Chem. Ind., 1 1, 141 (1892). 148 EXAMINATION OF CERTAIN OILS. or menhaden, and thoroughly stuffed with the oil in the " stocks." They are then piled in heaps, whereby a kind of fermentation or "heating" ensues, care being taken that the temperature does not rise too high, the process being complete when the leather assumes the well-known yellow color of chamois leather. It is well scraped with a blunt knife, washed with soda or potash, the emul- sion treated with acid, and the oil which rises to the surface is added to that obtained by scraping. Properties. It is a light or dark brown oil of peculiar odor, betraying its origin. Composition. Prepared in the way indicated, its composition must naturally be very varied; besides unchanged oil and free fatty acids, it con- tains a resinous substance or "degras-former," prob- ably a mixture of oxidized oils and their anhydrides. Jean 1 states that this is soluble in alcohol and ether, insoluble in petroleum spirit, and is saponifiable, but the soap is not precipitable by salt. Moellon also contains unsaponifiable matter coming from the oils used in its preparation. The following shows the results of the examina- tion of 12 sod oils found on the American market by Hopkins, Coburn, and Spiller. 2 The results are calculated in per cent, on the water-free oil and the acids in milligrams of KOH per gram of oil. 1 Mon. sci., 15 (1889). 2 J. Am. Chem. Soc., 21, 291 (1899). WASTE FATS. 149 ij i k i ll o.S Hide Fragmenl IJ Oxidized Acids. Free Fati Acids. 0.05 1.1 56.6 0.7 0.15 0.4 1.1 32.6 1.0 91.5 96.6 8.8 3.0 42.6 26.4 34.3 I Minimum. 1.0 Maximum. 40.6 Examination and Adulterants. The determina- tions to be made upon sod oil are indicated above; that of water is effected by mixing five grams of the sample with sand until a solid mass is obtained and drying at 110 C. It usually con- tains unchanged oil which is added to it after its formation, this cannot properly be regarded as an adulteration. Mineral and rosin oils may sometimes be found in it, obviously added with fraudulent intent. The specific gravity of the water-free degras is higher than that of the oils from which it is made; it varies from 0.945 to 0.955, and if it be as low as 0.920 an admixture with mineral oil is indicated. Uses. It is used for currying leather. Oil Foots. Preparation. The term " foots" is ap- plied by the oil and paint trade to any sediment obtained in the manufacturing or storing process. It is a mixture of oil, the impurities contained in the oil coming from the seed, or " mucilage/' as it is called, coloring matter, water, dirt, and where alkali has been used in the refining process, of the saponified oil or soap. Properties. Cotton-seed oil foots 1 or soap-stock varies in color from light, dirty yellow, through 1 Wesson, J. Soc. Chem. Ind., 26, 595 (1907). 150 EXAMINATION OF CERTAIN OILS. dark green to deep red, changing to black on ex- posure to the air. The odor is that of decomposed fish, due probably to methyl amine. If it contains more than 40 per cent, of water it ferments easily in hot weather and the soap made therefrom is poorer in color than that made from the fresh stock. Composition and Analysis. This has been given under preparation; it varies with the amount and strength of the alkalies used: the total fatty acids vary from 35 to 65 per cent., 45 being a fair average; less than 40 per cent, cannot be delivered on con- tracts. The specific gravity is from 0.97 to 1.04, 1.00 being the average. A typical analysis is as follows: Water 36.0 Fatty anhydrides 48.5 Glycerine 4.0 Caustic soda, Na 2 3.2 Color 2.4 Organic matter 5.8 Uses. It is used for the manufacture of soap, textile or mill soaps particularly, and is by far the cheapest soap-making material on the market. Many of the "washing powders " are composed of settled foots soap and soda ash. In England the foots are distilled with superheated steam after the manner of wool grease, which has already been de- scribed: an oleine, stearine, and cotton-seed stearine pitch are the products. Other foots beside cotton- seed are linseed, whale, sperm, and olive oil. Fuller's Grease. " Seek oil" (England), Recov- ered Oil. WASTE FATS. 151 Preparation. This is obtained from the water in which woolen cloth has been washed, by a pro- cess exactly similar to that by which wool fat is produced. It consists, therefore, of the oil which has been used in carding and spinning the wool, together with the fatty acids obtained from the scouring soap used, and those which existed in the oils as such. Olive, lard, neat's-foot, saponified, and distilled red, or "elaine oils/' " distilled grease," oleines and mineral oils, sometimes mixed with wool fat or degras, are some of the oils used for this pur- pose, or "wool oils." Composition. This will vary according to the oils and soaps used, and the results obtained should be compared with the constants of the oils origi- nally employed. If the oil is to be used again as a wool oil the spontaneous combustion and saponi- fication tests should be applied. Black Oil. This is the term applied to oil ex- tracted from the greasy waste of woolen mills and is, except for mineral oil coming from the machinery, the same as that upon the wool itself. It should not be confounded with a petroleum product, black oil, a crude petroleum from which naphtha and burn- ing oil have been distilled and used for freight-car lubrication. Garbage Grease. This is a grease obtained by the extraction of garbage with naphtha or carbon tetrachloride. It is used for the manufacture of cheap toilet soaps, or distilled as is wool fat. APPENDIX. TABLES, REAGENTS, AND RAILROAD SPECIFICATIONS. TABLE I. Requirement of Various States and Cities regarding Flash and Fire Test of Illuminating Oils. Name. Flash, F. Fire, F. Instrument. Arkansas 130 Tagliabue. Columbia, District of 120 Connecticut 110 Florida 130 Tagliabue. Georgia 120 Illinois 150 Tagliabue. Indiana 120 . . . Indiana. Iowa 105 ... Elliott. Kansas 110 Tagliabue. Kentucky 130 Louisiana 125 . . . Tagliabue. Maine 120 . . . Tagliabue open. Massachusetts 100 ... Tagliabue open. Michigan 120 148 Foster. Minnesota 110 . . . Minnesota. Missouri 150 Tagliabue. Montana 110 Nebraska 100 ... Foster. New Hampshire 100 120 Tagliabue. New Jersey 100 115 New Mexico 150 New York 110 Tagliabue. North Carolina 100 ... Foster. North Dakota 100 Ohio 120 ... Foster. 153 154 APPENDIX. Name. Flash, F. Fire, F. Instrument. Pennsylvania 110 Tagliabue. Rhode Island 110 South Dakota 110 ... Foster. Tennessee 120 ... Open cup. Vermont 110 Tagliabue. Wisconsin 120 . . . Wisconsin. Requirements of Cities where Different from State Law. Name. Flash, F. Fire, F. Instrument. Baltimore, Md 120 Denver, Col 110 ... Tagliabue open. Los Angeles, Cal 110 ... Tagliabue open. Meriden, Conn 125 Milwaukee, Wis 110 Newark, N. J 110 New Haven, Conn 110 Tagliabue open. New Orleans, La 110 Tagliabue open. New York, N. Y 100 ... Elliott. Richmond, Va 110 Tagliabue. Sacramento, Cal 110 ... Tagliabue open. San Francisco, Cal 100 . . . Tagliabue open. Wilmington, Del 110 TABLE II. Showing the Flash and Fire Test of Various Oils. 1 Flash, Flash, Fire, Fire, Name. C. Corn 249 Cotton-seed 305 Prime Lard 264 No. 2 Lard 215 Boiled Linseed 192 Raw Linseed 274 Menhaden Neat's-foot.. . 226 480 582 T530 1600 419 378 525 405 439 335 340 340 242 300 340 273 635 644 644 468 572 644 484 523 1 Done with the apparatus described upon page 40. APPENDIX 155 Flash, Flash, Flash, Fire, Name. C. F. F. F. Olive 233 451 283 541 25 Paraffine 210 410 246 475 75% 25 Paraffine, 25% Neat 's-foot. . . 210 410 244 471 75% 25 Paraffine, 25% Lard 210 410 254 489 50% 25 Paraffine, 50% Lard 218 423 267 513 25% 25 Paraffine, 75% Lard 227 441 284 543 Distilled Red 184 364 213 415 Sperm No. 1 220 428 270 518 Sperm No. 2 252 486 301 574 Flash Point of Certain Organic Compounds. Flash, Fire, Name. C.* "F. 1 F. 4 F.' *F. 8 81 53 54 62 Alcohol, + 0.5% ether ... 9 75 .. Alcohol, 4% by vol ... 68 181 Benzene, C e H 6 ... -8 45 Turpentine . . . 92-98 119-125 90 95 100 83-89 s Methyl Alcohol 45 52 56 Denatured Alcohol 55 50 58 Arptonfi 34 iRaikow Chem. Ztg. (1899), 145: Holde and Pelgry, Chem. Centralb. (1899) 2, 546. Done with Abel's tester and calculated to Massachusetts tester by adding 27 F. * Abel tester. Done in author's laboratory with N. Y. tester. 'Schieffelin, J. Soc. Chem. Ind., 27, 922 (1908), with Mass, open tester. McCandless, J. Am. Chem. Soc., 26, 982 (1904). 156 APPENDIX. TABLE III. Relation of Baume Degrees to Specific Gravity and the Weight of One United States Gallon at 60 F. 1 P Pounds in Gallon. Baume*. Specific Gravity. Pounds in Gallon. Baume. >> ll 8P OQ Pounds in Gallon. Baumd. Specific Gravity. Pounds in Gallon. 10 1.0000 8.33 31 0.8695 7.24 52 0.7692 6.41 73 0.6896 5.75 11 0.9929 8.27 32 0.8641 7.20 53 0.7650 6.37 74 0.6863 5.72 12 0.9859 8.21 33 0.8588 7.15 54 0.7608 6.34 75 0.6829 5.69 13 0.9790 8.16 34 0.8536 7.11 55 0.7567 6.30 76 0.6796 5.66 14 0.9722 8.10 35 0.8484 7.07 56 0.7526 6.27 77 0.6763 5.63 15 0.9655 8.04 36 0.8433 7.03 57 0.7486 6.24 78 0.6730 5.60 16 0.9589 7.99 37 0.8383 6.98 58 0.7446 6.20 79 0.6698 5.58 17 0.9523 7.93 38 0.8333 6.94 59 0.7407 6.17 80 0.6666 5.55 18 0.9459 7.88 39 0.8284 6.90 60 0.7368 6.14 81 0.6635 5.52 19 0.9395 7.83 40 0.8235 6.86 61 0.7329 6.11 82 0.6604 5.50 20 0.9333 7.78 41 0.8187 6.82 62 0.7290 6.07 83 0.6573 5.48 21 0.9271 7.72 42 0.8139 6.78 63 0.7253 6.04 84 0.6542 5.45 22 0.9210 7.67 43 0.8092 6.74 64 0.7216 6.01 85 0.6511 5.42 23 0.9150 7.62 44 0.8045 6.70 65 0.7179 5.98 86 0.6481 5.40 24 0.9090 7.57 45 0.8000 6.66 66 0.7142 5.95 87 0.6451 5.38 25 0.9032 7.53 46 0.7954 6.63 67 0.7106 5.92 88 0.6422 5.36 26 0.8974 7.48 47 0.7909 6.59 68 0.7070 5.89 89 0.6392 5.33 27 0.8917 7.43 48 0.7865 6.55 69 0.7035 5.86 90 0.6363 5.30 28 0.8860 7.38 49 0.7821 6.52 70 0.7000 5.83 95 0.6222 5.18 29 0.8805 7.34 50 0.7777 6.48 71 0.6965 5.80 30 0.8750 7.29 51 0.7734 6.44 72 0.6930 5.78 APPENDIX. 157 TABLE IV. Showing the Specific Gravity, Degrees Baume, and Weight per Gallon and per Cubic Foot of Certain Oils. Specific Gravity. Degrees Baume*. Pounds in One Gallon. Pounds in One Cubic Foot. Water 1 0000 10 8.33 62.50 Castor Oil .9639 15 803 60.24 Linseed Oil boiled .9411 19 784 58.81 Linseed Oil raw .9299 21 7.75 58.12 Menhaden, light .... .9325 20 7.77 58.28 Menhaden, dark .9292 21 7.74 58.08 Hemp-seed .9307 20 7.75 58.17 Cod Liver .9270 21 7.72 57.94 Whale .9254 21 7.71 57.84 PoDDv-seed .9243 21 7.70 57.77 Cotton-seed .9220 22 7.67 57.53 Fish .9205 22 7.67 57.53 Olive .9192 22 7.65 57.45 Almond .9180 23 7.65 57.38 Lard 9175 23 7 64 5734 Rape-seed .9155 23 7.63 57.22 Neat's-foot .9142 23 7.62 57.14 Colza .9136 23 7.61 57.10 Palm .9046 25 7.54 56.54 Sperm natural 8815 29 7.34 55.09 Sperm bleached .8813 29 7.34 55.08 Spirits of Turpentine .8600 33 7.16 53.75 Alcohol 90 per cent .8228 40 6.85 51.43 Alcohol 95 per cent .8089 43 6.74 50.56 Alcohol absolute . ... .7938 46 6.61 49.61 NOTE. In the columu marked Baume", the nearest whole number is given, omitting fractions. 158 APPENDIX. TABLE V. Comparison of SayboU's A Viscosimeter and Doolittle's Viscosimeter. Saybolt. Doolittle. Grams of Oil. Specific Gravity. Seconds. Sugar. StoveGasolene 680 23 0.0 Water 1.000 25 0.0 Kerosene, 150 Fire Test 783 26.8 3.3 Lantern, 300 Fire Test 827 36.4 49.8 Spindle 849 57.9 62.8 Spindle 851 60 65.5 Sperm 880 102 73.5 Spindle 863 115 74.3 Spindle 879 138 77.0 Spindle 868 156 78.4 Loom 888 203 80.6 Lard 916 215 82.8 Mineral 907 224 83.5 Neat's-foot 916 250 83.7 25Paraffine 900 272 84.2 Mineral.. 903 339 86.0 NOTE. Table V. was made from data obtained in the author's laboratory; Tables VI. and VII. are from those issued by George D. Feidt & Co., Philadel- phia, former makers of the torsion instrument. The results of Tagliabue's instrument should agree very closely with those obtained by the use of Sayboit's. APPENDIX 159 TABLE VI. A Comparison of Saybolt B and Torsion Viscosimeters, at 70 F. Saybolt B. Seconds. Torsion Grams Sugar per 100 cc. Solution. (Differ- ence) Grams Sugar. Saybolt B. Seconds. Torsion Grams Sugar per 100 cc. Solution. (Differ- ence) Grams Sugar. Uf 0.0 56 83.2 .2 15 9.2 9.2 57 83.4 .2 16 22.5 14.3 58 83.6 .2 17 36.5 14.0 59 83.8 .2 18 47.7 11.2 60 84.0 .2 19 53.5 6.8 61 84.2 .2 20 57.7 4.2 62 84.35 .15 21 60.6 2.9 63 84.5 .15 22 63.2 2.6 64 84.65 .15 23 65.6 2.4 65 84.8 .15 24 67.5 1.9 66 85.0 .2 25 69.2 1.7 67 85.15 .15 26 70.6 1.4 68 85.3 .15 27 71.6 1.0 69 85.45 .15 28 72.6 1.0 70 85.6 .15 29 73.4 .8 71 85.75 .15 30 74.0 .6 72 85.9 .15 31 74.6 .6 73 86.0 .1 32 75.2 .6 74 86.15 .15 33 75.6 .4 75 86.25 .1 34 76.0 .4 76 86.35 .1 35 76.5 .5 77 86.45 .1 36 76.9 .4 78 86.55 .1 37 77.4 .5 79 86.65 .1 38 77.8 .4 80 86.75 .1 39 78.2 .4 85 87.25 .50 40 78.6 .4 90 87.60 .35 41 79.0 .4 95 87.8 .20 42 79.3 .3 100 88.0 .2 43 79.7 .4 105 88.1 .1 44 80.1 .4 110 88.2 .1 45 80.4 .3 115 88.3 .1 46 80.75 .35 120 88.4 .1 47 81.0 .25 125 88.5 .1 48 81.3 .3 130 88.6 .1 49 81.6 .3 135 88.7 .1 50 81.85 .25 140 88.8 .1 51 82.2 .35 145 88.9 .1 52 82.4 .2 150 89.0 .1 53 82.6 .2 155 89.05 .05 54 82.8 .2 160 89.10 .05 55 83.0 .2 NOTE. Saybolt viscosimeter used gave a viscosity at 70 F. of 371 seconds for pure sperm oil of .886 specific gravity. 160 APPENDIX. TABLE VII. A Comparison of Saybolt C and Torsion Viscosimeters, at 212 F. Saybolt'C. Seconds. Torsion Grams Sugar per 100 cc. Solution. (Differ- ence) Grams Sugar. Saybolt a Seconds. Torsion Grams Sugar per 100 cc. Solution. (Differ- ence) Grams Sugar. 23 48.1 60 65.75 .2 24 49.2 1.1 61 65.95 .2 25 50.25 1.05 62 66.1 .15 26 51.3 1.05 63 66.25 .15 27 52.3 1.0 64 66.40 .15 28 53.2 .9 65 66.6 .20 29 54.0 .8 66 66.8 .2 30 54.75 .75 67 67.0 .2 31 55.5 .75 68 67.2 .2 32 56.2 .7 69 67.3 .1 33 56.85 .65 70 67.5 .2 34 57.5 .65 71 67.7 .2 35 58.0 .5 72 67.8 .1 36 58.5 .5 73 68.0 .2 37 59.0 .5 74 68.2 .2 38 59.45 .45 75 68.3 .1 39 59.85 .40 76 68.45 .15 40 60.25 .40 77 68.60 .15 41 60.6 .35 78 68.75 .15 42 60.9 .3 79 68.95 .2 43 61.25 .35 80 69.1 .15 44 61.6 .35 85 69.9 .8 45 61.95 .35 90 70.6 .7 46 62.3 .35 95 71.3 .7 47 62.6 .3 100 71.9 .6 48 62.9 .3 105 72.4 .5 49 63.2 .3 110 72.9 .5 50 63.45 .25 115 73.3 .4 51 63.7 .25 120 73.7 .4 52 64.0 .3 125 74.0 .3 53 64.3 .3 130 74.2 .2 54 64.5 .2 135 74.4 .2 55 64.7 .2 140 74.6 .2 56 64.9 .2 145 74.8 .2 57 65.15 .25 150 74.9 .1 58 65.35 .20 155 74.95 .05 59 65.55 .2 160 75.0 .05 NOTE. Saybolt viscosimeter used gave a viscosity at 212 F of 36$ seconds for pure sperm oil of .884 specific gravity. APPENDIX. 161 TABLE VIII. Comparison of Sayboli's A and the Engler Viscosimeter. Seconds. Saybolt A. Engler. Water 22.9 52.0 Neutral 46.1 119. XX Wool 105.2 320.5 Paraffine 127.2 379. Spindle 147.0 437.0 Lard.. . 216.7 686.0 TABLE IX. Showing the Principal Constants of Various Oils. o d -8 g-g NAME. E O Vajenta, Elaidin. I t || Refraction Index, 15-15.5 C. | S 03 5 eg Almond .918 110 53 Solid. 97 190 1.4728 Castor 963 Soluble * 47 84 181 1 4795-4803 Chinese Wood. . . . .940 40-47 163 193 1.503 s 8741 9 260 1 4573 Colza. (See Rape) Corn 922 80 85 Pasty 115 191 1 4768 Cotton-seed .922 90 2 -110 76 Pasty. 108 193 1.4737-4757 Elain 904 90 3 200 1 4631 T Horse... .919 54 68 80 5? 80 197 1. 4652-1 .4704 7 Lard 917 54 66 98 41 Very solid. 65 195 1 4694 Linseed .934 572-74 70-79 111 176 191 1.4835 Maize. (See Corn) Menhaden .930 642 1 2fi 154 190 1 .4783 7 Neat's-foot .915 62 72-75 46 Solid.s 71 194 1.4695-4705 Olive .916 85-111 35 Very solid. 8? 194 1.4703-4713 Palm 859 52 199 1 410 at 60F Peanut .917 872-112 51 Solid. P8 194 1.4731 Poppy-seed .925 87 138 193 1.4773 Rape .916 Insoluble. 55 Pasty. 101 174 1.4720-4757 Sesame 1 .923 872-107 65 Pasty. 107 190 1.4748-4762 Sperm .880 Insoluble. 46 Solid. 85 135 1.4664-4673 Sunflower .925 71 125 192 1.4762 TaUow 916 71-75 Solid. 56 197 1 4660 7 Whale .927 88 190 1 4691 7 iAt99C. Tolman and Munson, J. Am. Chem. Soc., 25, 244 (1903). APPENDIX. 165 REAGENTS. The reagents used in oil analysis are few and easily obtained. A list and their method of prepa- ration is here given. Acetic Acid, Glacial. Baker and Adamson's C. P. or Kahl- baum's "Eisessig," ninety-nine and five-tenths per cent. pure. The determination of its strength should be made by titration and not by specific gravity, as the ninety-eight per cent, and eighty per cent, acid have the same specific gravity, 1.067. The deter- mination of the melting point gives results equally good with those obtained by titration and requires less time. 1 It is made after the manner of the "titer test" (p. 82), the tube being half filled, chilled to 10 or 11 C., and further chilled by placing the outside bottle in ice-water; the temperature of the super-cooled acid rises to its melting point, where it remains stationary for some time. The melting points of acids of various strengths are as follows: 100 per cent., 16.75 C.; 99.5 per cent., 15.65; 99 per cent., 14.8. For Hanus's solution it must not reduce potassium bichromate and sulphuric acid. Acetic Anhydride. Baker and Adamson's C. P. or Kahlbaum's "Essigsaures Anhydrid." Alcohol. Commercial "Cologne Spirits." For the preparation of alcohol free from aldehyde for alcoholic potash, cologne spirits are treated with silver oxide as follows: one and one-half grams of silver nitrate are dissolved in 3 cc. of water, added to one liter of alcohol and thoroughly shaken; three grams of potassium hydrate are dissolved in 15 cc. warm alcohol and, after cooling, added to the alcoholic silver nitrate and thoroughly shaken again, best in a tall bottle or cylinder. The silver oxide is allowed to settle, the clear liquid siphoned off and distilled, a few bits of pumice, pre- pared by igniting it and immediately quenching under water, being added to prevent bumping. Alcohol for use in the free acid determination is prepared by placing ten to fifteen grams of dry sodium carbonate in the reagent bottle, taking care to filter it before use. Alcohol, Amyl. Kahlbaum's manufacture. i Mcllhiney et al., J. Am.Chem. Soc., 29, 1224 (1907). 166 APPENDIX. Bromine. The commercial article; also a 3 solution, made by dissolving 26.6 grams bromine in one liter carbon tetrachloride. Calcium Chloride. The dry and also the crystallized salt. Calcium Sulphate. Plaster of Paris. Carbon Tetrachloride. Baker and Adamson's C. P. or Kahl- baum 's " Tetrachlorkohlenstoff . ' ' Chloroform Squibb 's, U. S. P. Copper. Copper turnings or clippings, used for the generation of nitric oxide. Copper Wire. Cut in pieces of 0.3 to 0.5 gram. Ether. Squibb's, U. S. P. Gasolene. Gasolene, 86 Baume". Hydrochloric Acid, C. P. Specific gravity 1.2. For f HC1 dilute thirty-nine cubic centimeters of the above acid to one liter and standardize. Iodine Solution. Fifty grams of iodine to one liter of alcohol. For Hanus's solution dissolve by warming 13.2 grams iodine in one liter glacial acetic acid; cool and add three cubic centimeters of bromine. Lead, Precipitated. Place strips of zinc in the solution of lead acetate below. When the precipitation is nearly complete the lead is washed with water, alcohol, and ether, and dried finally in a vacuum desiccator. Lead Acetate. One hundred grams of the salt to one liter. Litmus Paper. Mercuric Chloride. Sixty grams of the salt to one liter of alcohol. Nitric Acid. Specific gravity 1.34. Phenolphthalein. One gram of the substance to five hundred cubic centimeters of alcohol. M eta-Phosphoric Add. A saturated solution of the commercial "stick phosphoric acid" in absolute alcohol. Potassium Bichromate. Dissolve 3.8747 grams of the C. P. salt in one liter of water; one cubic centimeter is equivalent to 0.01 gram of iodine. The solution should be tested against iron wire containing a known percentage of iron. Potassium Hydrate. f: Dissolve thirty grams of "potash by alcohol" in one liter of alcohol. : Dissolve ten grams of ordi- nary " stick potash ' ' in one liter of water and dilute to proper strength. The solution should be protected by stick potash from the carbon dioxide in the air. Ten per cent.: Dissolve one hun- APPENDIX. 167 dred grams of "stick potash" in eleven hundred cubic centimeters of alcohol. Potassium lodate. A two per cent, solution. Potassium Iodide. One hundred grams of the commercial salt are dissolved in one liter of water. This should be free from iodate, shown by yielding no coloration when acidified with strong HC1. Silver Nitrate. Thirty grams to one liter + 0.4 Cc. HNO,. Sodium. Sodium Chloride. Ordinary "coarse fine" salt for freezing mixtures. Sodium Hydrate. 36 Baume*. Dissolve three hundred grams of caustic soda in one liter of water. Sodium Nitroprusside. The commercial salt. Sodium Thiosulphate. y^-: Dissolve twenty-six grams of "sodium hyposulphite" in one liter of water; the addition of two grams of ammonium carbonate to the liter is said by Mohr to improve the stability of the solution. Starch Solution. Rub up in a mortar one gram of potato starch with ten to fifteen cubic centimeters of water, pour this into two hundred cubic centimeters of water which are boiling actively, and continue the boiling for a few minutes. Sugar. Ordinary granulated sugar. Sulphur. A 1.5 per cent, solution in carbon bisulphide. Sulphuric Acid, C. P. This should be at least ninety-nine and five-tenths per cent, pure, and its strength be determined by titra- tion, as one hundred per cent, and ninety-four and three-tenths per cent, acid have the same specific gravity, 1.8384. 1 Dilute. One part acid to ten parts of water. Nitrosulphuric Acid, for the Elaidin Test. A liter of sulphuric acid of 46 Baume" (1.47 specific gravity) is prepared by diluting five hundred and sixty cubic centimeters commercial sulphuric acid to one liter; a few drops of nitric acid are added and nitric oxide (generated from copper and nitric acid) passed in until it is saturated. The acid is then cooled in ice-water and the gas passed in until it is saturated at C. This is called Roth's liquid. Tin Tetrabromide. This is prepared 2 by allowing bromine to fall drop by drop upon granulated tin contained in a dry flask im- i Richmond, J. Soc. Chem. Ind., 9, 479 (1890). 1 Allen, Commercial Organic Analysis, ii, 463. 168 APPENDIX. mersed in cold water until the coloration shows bromine to be in excess. A small quantity of bromine is then added and the liquid diluted with three to four times its volume of carbon bisulphide. OILS FOR RAILROAD USE. The railroads being among the largest users of oil, their requirements are of interest; as they do not differ widely, those of the Philadelphia and Reading Railroad will serve as a sample. Specifications for Lard Oil. When a shipment of oil is received a sample will be taken at random from each sixty barrels or fraction thereof, and forwarded to the Test Department. This sample will be examined and the entire shipment accepted or rejected on its merits. If rejected the shipment will be returned at the shipper's expense. Two grades of Lard Oil will be used, "Prime" and "Extra No. 1"; the former for burning purposes chiefly, and the latter as a lubricant. The material desired under this specification is oil from fresh lard of corn-fed hogs, unmixed with other oils. It should contain the least possible amount of free acid, and from October 1 to May 1 show a cold test not higher than 40 F. PRIME LARD OIL. This grade of oil must not contain admixtures of any other oils or more free acid than is neutralized by four cubic centimeters of alkali, as described below. Between October 1 and May 1 it must show a cold test below 45 F. When tested with nitrate of silver, as described below, it must not show any coloration. EXTRA No. 1 LARD OIL. This grade of oil must not contain admixtures of any other oils or more free acid than is neutralized by thirty cubic centimeters of alkali, as described below. Between October 1 and May 1 it must show a cold test below 45 F. The Cold Test. The cold test is made as follows: APPENDIX. 169 About two ounces of oil are put in a four-ounce sample bottle, a thermometer inserted, and the oil frozen with ice, salt being used if necessary. When the oil is hard, the bottle is taken from the freezing mixture and the frozen oil stirred thoroughly with the thermometer until it will flow. The reading of the thermometer is then taken, and this temperature is regarded as the cold test of the oil. Free Add Test. The solutions required for this test are ninety- five per cent, alcohol neutralized with sodium carbonate, caustic potash solution of such a strength that 31.5 cubic centimeters of it will exactly neutralize five cubic centimeters of a normal solution of sulphuric acid (forty-nine grams per liter), and a small amount of Phenolphthalein dissolved in Alcohol, and rendered neutral with caustic potash, to be used as an indicator. Now weigh or measure into a four-ounce sample bottle 8.9 grams of the oil to be tested, add about two ounces of Alcohol, warm to about 150 F., and add a few drops of the Phenolphthalein. Then run in the caustic potash from a graduated burette, with frequent shaking, until a permanent pink color remains after vigor- ous shaking. When this point is reached read the number of cubic centimeters used. Nitrate of Silver Test. Solution of Nitrate of Silver is made as follows: Nitrate of Silver, 1 gram; Alcohol, 200 grams; Ether, 40 grams. After the ingredients are dissolved and mixed, allow the solution to stand in a bright light until it has become perfectly clear; it is then ready for use, and should be kept in a dim place, and tightly corked. Into a fifty cubic centimeter test-tube put ten cubic centimeters of the oil to be tested, previously filtered through washed filter- paper. Add five cubic centimeters of the above solution, shake thoroughly, and heat in a vessel of boiling water fifteen minutes with occasional shaking. If the oil is satisfactory it will show no change of color under this test. Specifications for Petroleum Products. When a shipment of oil is received, a sample shall be taken at random and forwarded to the Test Department. This sample will be examined and the entire shipment accepted or rejected on its merits. If rejected, the shipment will be returned at the shipper's expense. 170 APPENDIX. 150 FIRE TEST OIL. This grade of oil shall be water-white in color, showing a flash- ing point not below 130 F., and a burning point not below 151. The test will be made in an open vessel by heating the oil not less than ten degrees per minute, and applying the test flame every seven degrees, beginning at 123. The gravity may be from 46 to 50 Baume\ Oil will not be received which is cloudy from the presence of glue or suspended matter of any kind. 300 FIRE TEST OIL. This grade of oil shall be water-white in color, show a flashing point not below 256 F., and a burning point not below 298. The test will be made in an open vessel by heating the oil not less than fifteen degrees per minute, and applying the test flame every seven degrees, beginning at 249. When heated to a temperature of 425 and held there for five minutes, the oil must remain clear and transparent, showing but a slight darkening and no separation of flocculent or other matter, either at this temperature or on cooling. When the oil is cooled to the temperature of 32, and held there for ten minutes, it must remain clear and transparent, showing no cloudiness. The gravity may be from 38 to 42 Baume*. Oil will not be received which is cloudy from the presence of glue or suspended matter of any kind. CAR OIL. This grade of oil, commonly known as Well Oil or Black Oil, should have a gravity of about 29 Baume", and must not show a flashing point below 325 F. The test will be made in an open vessel by heating the oil not less than fifteen degrees per minute, and applying the test flame once in seven degrees, beginning at 304. Oil received during the months of August and September must have a cold test not above 15 F., and from October 1 to April 1, a cold test not above 5 F. when determined as described below. From August 1 to April 1, at 80 F., the oil must show a vis- cosity not lower than that of a pure cane sugar solution containing eighty grams of sugar in one hundred cubic centimeters of the syrup, and at 150 F. a viscosity not lower than that of a pure cane sugar solution containing sixty-six grams of sugar in one hundred cubic centimeters of the syrup, the viscosity of the sugai solution being taken at 80 F. APPENDIX. 171 From April 1 to August 1, at 80 F., the oil must show a vis- cosity not lower than that of a pure cane sugar solution containing eighty-eight grams of sugar in one hundred cubic centimeters of the syrup, and at 150 F. a viscosity not lower than that of a pure cane sugar solution containing sixty-eight grams of sugar in one hundred cubic centimeters of the syrup, nor higher than that given by a pure cane sugar solution containing seventy-five grams of sugar in one hundred cubic centimeters of the syrup, the viscosity of the sugar solutions being taken at 80 F. The oil must be transparent with a reddish-brown or greenish color, free from lumps or specks. No oil will be accepted which shows more than five per cent, of flocculent or tarry matter settled out after five cubic centimeters of the oil have been mixed with ninety-five cubic centimeters of 88 Gasolene, and allowed to stand for an hour. CYLINDER STOCK. This grade of oil shall show a flashing point not below 525 F., and a burning point not below 600 F. The test will be made in an open vessel by heating the oil not less than twenty degrees per minute, and applying the test flame every seven degrees, beginning at 504. This oil must flow readily at 60 F., and at 350 F. must show a viscosity not lower than that of a pure cane sugar solution con- taining fifty-eight grams of sugar in one hundred cubic centimeters of the syrup, the viscosity of the sugar solution being taken at 80 F. The oil must be transparent, with a reddish-brown or greenish color, free from lumps or specks. No oil will be accepted which shows more than five per cent, of flocculent or tarry matter settled out after five cubic centimeters of the oil have been mixed with ninety-five cubic centimeters of 88 Gasolene, and allowed to stand for one hour. Cold Test. About two ounces of oil are put in a four-ounce sample bottle, a thermometer inserted, and the oil frozen with a mixture of ice and salt. When the oil is hard the bottle is taken from the freezing mixture and the frozen oil stirred thoroughly with the thermometer until it will flow. The reading of the ther- mometer is then taken, and this temperature is regarded as the cold test of the oil. 172 APPENDIX. NOTE. The viscosity tests will be made upon the Torsion Vis- cosimeter. Manufacturers not having this instrument may submit a sample of oil to the Test Department, and will be furnished with the infor- mation necessary to standardize the viscosimeter they may have in use. Specifications for Compound Oils. When a shipment of oil is received, a sample shall be taken at random and forwarded to the Test Department. This sample will be examined and the entire shipment accepted or rejected on its merits. If rejected, the shipment will be returned at the shipper's expense. CYLINDER OIL. This oil shall consist of a high-grade cylinder stock, compounded with not less than twenty per cent, by weight of acidless animal oil, Tallow or Tallow Oil being preferred. The compounded oil shall show a flashing point not below 525 F., and a burning point not below 600. The test will be made in an open vessel by heating the oil not less than twenty degrees per minute, and applying the test flame every seven degrees, beginning at 504. This oil must flow readily at 60 F., and at a temperature of 350 F. must show a viscosity not lower than that of a pure cane sugar solution containing fifty-eight grams of sugar in one hundred cubic centimeters of the syrup, the viscosity of the sugar solution being taken at 80 F. The oil must be transparent, with a reddish-brown or greenish color, free from lumps or specks. No oil will be accepted which shows more than five per cent, of flocculent or tarry matter settled out after five cubic centimeters of the oil have been mixed with ninety-five cubic centimeters of 88 Gasolene, and allowed to stand for one hour. SIGNAL OIL. This grade of oil shall be prime white in color, shall contain not less than forty per cent, by weight of Prime Lard Oil, and shall show a flashing point not below 200 F., and a burning point not above 300. The test will be made in an open vessel by heating the oil not less than fifteen degrees per minute, and applying the test flame every seven degrees, beginning at 193. APPENDIX. 173 When heated to a temperature of 450, and held there for five minutes, the oil must remain clear and transparent, showing but a slight darkening and no separation of flocculent or other matter, either at this temperature or on cooling. The gravity may be from 31 to 34 Baume*. Oil will not be received which is cloudy from the presence of glue or suspended matter of any kind. No. 1 ENGINE OIL. This oil shall consist of a high grade of mineral oil, compounded with not less than ten per cent, by weight of nearly acidless animal oil. It shall show a gravity of about 29 Baume*, and a flashing point not below 325 F. The test will be made in an open vessel by heating the oil not less than fifteen degrees per minute, and applying the test flame once in seven degrees, beginning at 304. Oil received during the months of August and September must have a cold test not above 15 F., and from October 1 to April 1 a cold test not above 5 F., when determined as described below. From August 1 to April 1, at 80 F., the oil must show a vis- cosity not lower than that of a pure cane sugar solution containing eighty grams of sugar in one hundred cubic centimeters of the syrup, and at 150 a viscosity not lower than that of a pure cane sugar solution containing sixty-six grams of sugar in one hundred cubic centimeters of the syrup, the viscosity of the sugar solution being taken at 80 F. From April 1 to August 1, at 80 F., the oil must show a vis- cosity not lower than that of a pure cane sugar solution containing eighty-eight grams of sugar in one hundred cubic centimeters of the syrup, and at 150 F. a viscosity not lower than that of a pure cane sugar solution containing sixty-eight grams of sugar in one hundred cubic centimeters of the syrup, nor higher than that given by a solution of pure cane sugar containing seventy-five grams of sugar in one hundred cubic centimeters of the syrup, the viscosity of the sugar solutions being taken at 80 F. The oil must be transparent, with a reddish-brown or greenish color, free from lumps or specks. No oil will be accepted which shows more than five per cent, of flocculent or tarry residue settled out after five cubic centimeters of the oil have been mixed with ninety-five cubic centimeters of 88 Gasolene, and allowed to stand for an hour. 174 APPENDIX. No. 2 ENGINE OIL. The requirements for this oil are identically the same as those for No. 1 Engine Oil, with the following exceptions: It must contain not less than twenty per cent, by weight of nearly acidless animal oil. From October 1 to April 1 the cold test must be not above 10 F. when determined as described below. SCREW-CUTTING OlL. This oil shall consist of paraffine oil of about 27 Baume* gravity, compounded with not less than twenty-five per cent, by weight of Fat Oil, Cotton-seed preferred. The compound oil shall show a flashing point not below 300 F., and a burning point not above 425. The test will be made in an open vessel by heating the oil not less than fifteen degrees per minute, and applying the test flame once in seven degrees, begin- ning at 276. From October 1 to April 1 the oil must have a cold test not above 15 F. when determined as described below. Cold Test. About two ounces of oil are placed in a four-ounce sample bottle, a thermometer inserted, and the oil frozen with a mixture of ice and salt. When the oil is hard, the bottle is taken from the freezing mixture, and the frozen oil stirred thoroughly with the thermometer until it will flow. The reading of the ther- mometer is then taken, and this temperature is regarded as the cold test of the oil. NOTE. The viscosity tests will be made upon the Torsion Vis- cosimeter. Manufacturers not having this instrument may submit a sample of oil to the Test Department, and will be furnished with the infor- mation necessary to standardize the instrument they may have in use. Specifications for Tallow. Tallow to be used for cylinder lubrication should be rendered as soon as possible after the animal is killed, in order to have the amount of free acid as small as possible. Tallow which on examination is found to contain dirt or crack- lings disseminated through it, or which has a layer of dirt or crack- lings in the bottom of the barrel more than an eighth of an inch thick, will be rejected. APPENDIX. 175 Tallow will not be accepted which has more free acid than can be neutralized by three cubic centimeters of the alkali solution used for this determination (p. 78), or which contains any foreign substance not properly belonging to tallow. Specifications for Transformer Oil. Transformer oils l should be either pure mineral or rosin oils and be free from water, acid, and alkali. Heated in Holde's apparatus for two hours at 170 they should lose less than, one per cent. (Holde's apparatus consists of a copper cup 55 mm. in diameter and in depth, which is filled to within 2 cm. of the top and heated in a glycerine or other suitable bath.) The viscosity should be low, less than 408 second Saybolt at 70 F. They should remain liquid at C. The flash point should be not less than 190 C. in the open tester. iHolde, Schmiermittel Untersuchung, p. 66, 1905. INDEX Acid, arachidic, 115. Acidity, detection of, 23, 78. Adulteration, calculation of, 62. Animal oils, test for, 90. Antifluorescents, detection of, 43. Bach's test, 77. Baudouin's test, 76. Baume hydrometer, 19. Bechi test, 72. Benzine, deodorized, 100. Black oil, 151. Bromine number, 63. Burning oil distillate, 99-101. oils, 13, 101. Canadol, 100. Caoutchouc, 43. Chilling point, 39. Cholesterol, melting point of, 92. esters, melting point of, 92. test for, 92. Cold test, 38. Color of oils, 9. reactions, 72. Cotton-seed oil test for, 74. Cymogene, 100. Danforth's oil, 100. Degras, 141, 147. Determination of mineral salts, 24. of sulphur, 21. of water, 24. Distillation test, 20. Distilled grease, 144. oleines, 144. stearines, 144. Drying test, 81. Elaidin test, 51. Evaporation test, 37. Export oil, 101. Fatty oils, test for, 45. Fire test, burning oils, 19. lubricating oils, 41. Flash point, burning oils, 13. conditions influencing, 14. lubricating oils, 40. test, 13. Fluorescence, observation of, 45. Foots, 149. Free acid test, 78. Freezing mixtures, 39. Friction machines, 46. tests, 46. Fuller's grease, 150. Garbage grease, 151. Gasolene, 100. Gumming test, 45. Halphen's test, 74. Hanus's method, 56. Headlight oil, 101. Heat of bromination test, 55. Hexabromide test, 105. Hubl's method, 58. Iodine number, 55. oxidized oils, 63, 127. Kerosene, 101. Koettstorfer's method, 65. Lanoline, 144. Liebermann-Storch test, 120. Ligroine, 101. Livache test, 81. Lubricants, 86. Lubricating oil distillate, 99, 101. oils, 26. Mackey's apparatus, 78. Maumeng test, 52. 177 178 INDEX. McHhiney's method, 63 Mineral salts, effects of, in burning oils, 24. sperm, 101. Moellon, 147. Naphtha, 100. distillate, 99. Nitro-benzene, 43. naphthalene, 43. Odor of oils, 9, 89. Oil, almond, 113. arachis, 114. black, 151. castor, 112. Chinese wood, 106. cocoanut, 129. cod, 133. corn, 108. cotton-seed, 109. earthnut, 114. elain, 138. horse, 135. Japanese wood, 106. jaw, 87. lard, 135. linseed, 103. bleached, 105. boiled, 104. maize, 108. "melon," 87. menhaden, 132. neat's-foot, 134. olive, 117. palm, 128. peanut, 114. poppy-seed, 107. "pulp," 42. rape, 111. blown, 127. red, 138. rosin, 118. sesame*, 110. sod, 147. sperm, 139. sunflower, 108. tallow, 137. "thickener, "42. transformer, 175. tung, 106. Oil, whale, 133. Oils, animal, 49. blown, 127. burning, 13, 101, 170. classification of, 97. clock, 87. cylinder, 87, 101, 172. drying, 103. engine, 87, 101, 173. loom, 101. lubricating, 26, 87. machinery, 87. neutral, 101. non-drying, 113. oxidized, iodine number of, 63. paraffine, 102. semi-drying, 108. spindle, 87, 101. vegetable, 49. watch, 87. Oil foots, 149. Petroleum ether, 100. Phytosterol, melting point of, 92. esters, melting point of, 92. test for, 92. Prices of oils, 88. Reagents, 165. Renard's test for rosin oil, 120. Rhigolene, 100. Rosin, grades of, 122. spirits, 121. Saponification value, 65. Sesame" oil, test for, 76. Sherwood oil, 100. Soap, detection of, 42. Sod oil, 147. Specific gravity, 19, 36, 49, 89. Specifications for oils, 86, 108. car oil, 170. cylinder oil, 171, 172. stock, 171. engine oil, 173, 174. 150 fire test, 170. 300 fire test, 170. lard oil, 168. screw-cutting oil, 174, signal oil, 172. tallow, 174. INDEX. 179 Specifications for transformer oil, 175. Spontaneous combustion test, 78. Sulphur in oils, 21. Sulphuric acid test for burning oils, 23. Tables: I., flash and fire test, re- quirements, 153. II., flash and fire test, various oils, 154. III., Baumd, degrees and specific gravity, 156. IV., specific gravity and weight of oils, 157. V. VIII., comparison of viscosi- meters, 158-161. IX., constants of various oils, 161. X., volumetric factors, 162. XI., action of oils upon metals, 162. XII., constants of fatty acids from various oils, 163. XIII., bromine addition and sub- stitution figures, 163. XIV., comparison of Hubl, Hanus, and Wijs iodine values, 164. Test, animal oils, 90. Bach's, 77. Baudouin's, 76. Bechi, 72. Camoin's, 76. cold, 38. distillation, 20. drying, 81. elaidin, 51. evaporation, 37. fatty oils, 45. fire, 19, 41. flash, 13, 40. free acid, 78. gumming, 45. Test, Halphen's, 74. Hanus's, 130. heat of bromination, 55. hexabromide, 105. Liebermann-S torch, 120. Livache, 81. Maumend, 52. Renard, 120. soap, 42. spontaneous combustion, 78. titer, 82. Valenta's, 50. vegetable oils, 90. Tester, covered, 15. Massachusetts, 18. New York State, 15. Tagliabue, open, 18. Titer test, 82. Turpentine, 122. wood, 126. Unknown oil, examination of, 88. Unsaponifiable oils, detection of, 68. examination of, 70. Valenta test, 50. Vegetable oils, test for, 90. Viscosimeter, Doolittle's, 33. Saybolt's"A,"27. Saybolt's"C,"29. Universal, 30. Traube's, 35. Viscosimetrical tables, 158161. Viscosity, definition of, 26. Water, determination of, 24. Westphal's balance, 36. "White Gelatin, "42. Wool fat, 141. grease, 141. THIS BOOK IS DUE ON THE LAST DATE STAMPED BELOW AN INITIAL FINE OF 25 CENTS WILL BE ASSESSED FOR FAILURE TO RETURN THIS BOOK ON THE DATE DUE. THE PENALTY WILL INCREASE TO SO CENTS ON THE FOURTH DAY AND TO $1.OO ON THE SEVENTH DAY OVERDUE. SEP 5 1933 APR 8 1936 MAR 19 1940 REC'D LO NOV 619S7 LD 21-50m-l,'3i X ;