A’OTES A N D CORRESPO-YDESCE.
‘
thrown out and may be collected if the alcoholic solution is distilled off. n‘ith equal ease the platinum may be recovered from the potassium platinochloride obtained when the crystals are dissolved from the Gooch crucibles. If a little alcohol is added to this solution and it is allowed t o stand in direct sunlight for a few weeks, the bottles being kept tightly stoppered, the platinum is finally deposited a s platinum black and a clear solution remains. The platinum may then be collected and purified as in the case of the alcoA. W. BLAIR. holic wash. FLORID % AGRICULTURAL EXPERIMEXT STATIOS
THE TRUE MELTING POINT OF TRINITROTOLUENE. Inasmuch a s the determination of the purity of the C. P. trinitrotoluene of commerce is based to a large extent on the melting point, a n accurate determination of the true value of t h a t constant has become of importance. The trinitrotoluene in question is the a-z-4-6-compound, and is obtained as the final product by nitration of C. P. toluene with a mixture of nitric and sulphuric acids. The crude product is purified by recrystallization from suitable solvents, alcohol being the one usually used, and it is then obtained in the form of small prismatic crystals of a light yellow or brownish color. The true melting point of the C. P. material has been generally accepted as 82’ C., according to Beilstein, Richter, etc. The authority for this melting point is Wilbrand,’ who described the preparation of the substance in 1863, and stated that the melting point is “etwa Sz‘.” Later, in 1875,E. J. Mills2 prepared trinitrotoluene in two ways: His first product from nitrating toluene with fuming nitric acid and then treating with a mixture of fuming nitric and sulphuric acids, with recrystallization from naphtha and alcohol, had a constant melting point of 78.85’, which was not changed by boiling 36 hours with fuming nitric acid. A second product was obtained by treating “solid,” by which presumably para mono-nitrotoluene is meant, with fuming nitric and sulphuric acids. This product, when purified, had a constant melting point of 80.54’. I n a later article in 1882, determined the melting points of various benzene derivatives, which were most carefully purified by recrystallization, a n d found 7 8 . 8 5O for the melting point of trinitrotoluene. The subject has been investigated a t the Eastern laboratory, and all available samples of trinitrotoluene that were supposed t o be pure were tested with the following results: 1.
2. 3.
5.
6.
Melting point. Sample of 1-2-4-6-trinitrotoluene from Kahlbaum.. . 80.50 Another siim ‘trotoluene from Kahlbaum. .................... 79 , s o Same sampie crystallized three times from .......... 80.l0
A product with a sharp melting point a t 80.6’ (corrected) was obtained. This product was further nitrated again with a mixed acid of the same composition, but the melting point of the product was not changed thereby. The melting point determinations were made most carefully by the capillary method, using a fine capillary and the smallest possible amount of substance. The melting points in all cases were sharp, and the necessary corrections for emergent thread were made. The experimental work connected with this investigation was carried on by Dr. C. h1. Stine and 31r. C. C. Ahlum, t o whom I wish t o express my thanks. A. M. COMEY. EASTERS
LABORATORY,
E. I. DUPOST DE YEXIOURSPOWDER Co., December 22. 1909.
NOTE ON A CONDENSER USED FOR EXTRACTION. Its main advantages are Al (I) t h a t it has a large cooling surface (necessary in the case D of lowboiling solvents) and (2) that the solvent may be almost wholly recovered while the flask is still connected to the condenser (economical in the case of extractions by ether, acetone, etc.). The total length of the condenser is thirty-five (35) inches. I t has been used together with flasks similar to those described by Albert P. Sy,’ for about a year and has given satisfaction. Instead of a platinum perforated disk extraction tube, one having a diameter of thirteen - sixteenths (13/16) inches a t “ A ” (see figure) a n d seventeen - sixteenths (17116) inches a t “ B ” is conveniently u s e d . T h e substance to be extracted is weighed into a ( 2 2 x 80 mm.) thimble, which easily fits into the tube. DAVIDBL0oR.f.
.........
lized three times from alcohol. . . . . . . . . 80.6’ Samples from various lots of English C . P. trini tro toluen 80 . 5 ‘-80 . 6 Trinitrotoluene ern laborator toluene and 80.50
Finally, in order to determine the true melting point of trinitrotoluene, commercial C. P. toluene was carefully fractionated in the laboratory until a large quantity of a product boiling constant a t 110.7’ (corrected) at 760 mm. pressure was obtained. This was nitrated in the usual way with a mixture of nitric and sulphuric acids, and the product recrystallized. Annalen. 128, 178. P h i l . M a g . . [4] 6 0 , 17. I b i d . , [ 5 ] 14, 27.
BUREAU OF STANDARDS, ANALYZED SAMPLES. The Bureau of Standards, Washington, D. C., is ready t o distribute Bessemer steels with 0.6 and 0 . 8 carbon, and a n iron C to replace that originally prepared by the American Foundrymen’s Association. The new C has the following composition: Total C, 2 . 7 8 ; graphite, 2 . 2 2 ; Si, I .84; Ti, 0.074; P, 0.192; S by oxide, 0.0354; S by evol., 0.0335; Mn, 0 , 7 4 4 . A new iron B was found t o need remixing and partial analyIt is hoped that the sample will be ready to distribute sis. by the time this notice appears in print. A vanadium steel and a n ore of manganese await the reconciling of differences in the analytical results reported. Three Lake Superior iron ores are undergoing analysis: one to serve as a standard for iron, phosphorus and silicon; the THISJ O U R N A L , 1, 314 (1909).
T H E J O C R N A L OF I N D U S T K I S L A N D ENGINEERTXG C H E M I S T R Y .
I04
second for aluminum, calcium and magnesium; and the third for manganese. POSSIBLE CONTAMINATION OF ACETIC ANHYDRIDE USED I N THE LIEBERMANN-STORCH REACTION. The note by Waters and Beneker on casein tests,’ with incidental reference to the Liebermann-Storch reaction for rosin, calls attention t o the fact, not sufficiently emphasized in the books, t h a t this test gives positive results with many gums, waxes, and oils. Further, much of our acetic anhydride comes with the glass stopper sealed with a wax which itself gives the Liebermann-Sforchreaciion. This should be noted, for unless the stoppers are cleaned, carefully and scrupulously, the acetic anhydride may be itself so charged with resinous material as to appear to give the test, even with substances which are really neutral or indifferent t o the test. That the acetic anhydride bottles so sealed are from a leading drug-and-chemical house is only another illustration of the necessity for eternal vigilance in watching the purity of our reagents. CHAS.S. PALMER. NORWOOD, MASS.
BOOK REVIEWS AND NOTICES. A Text-Book of Botany and Pharmacognosy. By HENRY KRAEMER,PH.D., Professor of Botany and Pharmacognosy of Philadelphia College of Pharmacy. Third revised edition. 850 pp. Philadelphia: J. B. Lippincott Co. The subjects are clasified a s follows: Part I, Botany. Part 11, Pharmacognosy: Chapter I, Crude Drugs; Chapter 11, Powdered Drugs and Foods. Part 111, Reagents and Microscopical Technique. The sections devoted t o botany are abundantly, accurately and excellently illustrated, while the subject-matter is presented in a n unusually clear manner. Under Pharmacognosy of the Crude Drugs, we find the information relative t o their chemistry, thorough and up-to-date. The common adulterants and also the allied plant products are detailed under each drug, a knowledge of which is of primary importance to-day, when adulteration and substitution among crude and powdered drugs is so prevalent. The chapter on Powdered Vegetable Drugs and Foods is especially recommended to food and pharmaceutical chemists, a subject so little known and of such primary importance since the enactment of the Food and Drugs Act. Any analyst upon carefully studying this chapter will discover the invaluable uses of the microscope, an instrument very much negl’ected in our chemical institutes. The chapter devoted to reagents and methods of staining, mounting and micrometry is a valuable feature, but still more t o be commended is the application of the micro-polariscope, so very useful in this as well a s other branches of chemical research. Professor Kraemer is to be congratulated in having presented a n original and valuable reference as well as text-book, which should occupy a prominent place on the shelves of every food V. CORLENTZ. analyst. The Manufacture of Paper. By R. W. SISDALL, F.C.S., London. New York: D. Van Nostrand Co. 1908. Price, $2 .oo net. This purports t o be a n elementary text-book which confines itself t o a n outline of the various stages of the paper manufacture and some of the more recent improvements in the industry. From whatever point of view it is considered, the book must be adjudged a contribution of very moderate value t o the literature of the art. I t s material has been brought together many times before and in its present arrangement takes on no new aspect. As a text-book, “The hlanufacture of Paper” fails to meet several fundamental requirements. There T H l S JOURNAL.
2, 28 (1910).
Mar., 1910
is no clear statement or logical development of general principles, definitions are often inexact and descriptions superficial rather than concise. Cellulose, for example, is hardly to be defined as “paper pulp” or even a s “this fibrous substance.” We do not speak of “ a vegetable plant.” Parchment is quite a different thing from parchment paper. Celluloid is not always “ a plastic, ivory-like substance.” No reference is made to the necessity of tension if mercerization of cotton is to produce silky luster; the paragraph on artificial silk is carelessly inaccurate and there is no mention under “Viscose” of the regeneration of cellulose through decomposition of the material, although the commercial developments of viscose are based upon this regeneration. There are 58 illustrations, most of which can be of little assistance to the student through lack of adequate description in the text. The chapter on the chemicals used in paper making is most casual in its treatment. The best parts of the book are those which relate to beating, a subject which has been much more fully treated by Beadle, and to dyeing and coloring, which have been far more adequately presented by Erfurt. The book concludes with a valuable bibliography, the most complete which we have seen, and a brief index. A really comprehensive and up-to-date textbook of paper-making is much needed and it should easily lie within Mr. Sindall’s powers to produce it. I t is to be regretted that he has not done so in the present volume. A. D. LITTLE’. Allen’s Commercial Organic Analysis. 4th Edition. Vol. I. Edited by HENRY LEFFXASNand W. A. DAVIS,assisted by the following contributors: E. F. ARNSTRONG,J. L. BAKER, G. C. JONES, E. SCHLICHTIXG and R. W. SINDALL. Philadelphia: P. Blakiston’s Son 81 Co. Large 8vo. Cloth. 576 pp Price, $5 .oo net. I n preparing the present edition of this well-known standard work, the editors a n 8 contributors have followed in the main the arrangement of the previous editions. It has been found necessary, however, to turn over the writing of the various parts to spec alists, and in their selection both sides of the Atlantic have been drawn upon, thus making the work international in character. The introduction of the present volume is by 1%’. A. Davis and covers the general methods of commercial organic analysis. Alcohols are treated by G. C. Jones; Malt and Malt Liquors, by Julius L. Baker; Wines and Potable Spirits, by G. C. Jones; Yeast, by .Emil Schlichting; Neutral Alcoholic Derivatives, by Henry Leff mann; Sugars, by E. Frankland Armstrong; Starch and I t s Isomers, by E. Frankland Armstrong; Paper and Paper-Making Materials, by R . W. Sindall; Acid Derivatives of Alcohols, by Henry Leff mann. It will be seen from these several divisions that a considerable part of the subject-matter is altogether new, notably the chapters on least and on paper and paper-making materials. The number of pages have been increased from 557 to 576, but the increase of matter is more than would be covered by the increase in the number of pages. The descriptive treatment, which characterized Sllen’s works in previous editions, is retained in the present and is to be commended in a work of this character. Analysts who have used the previous editions with profit will find the present edition valuable, although since it is written by a number of authors, all parts cannot be absolutely equal in merit, and only repeated use will determine the actual merit of the various parts. The paper, typogW. D. RICHARDSON. raphy and binding are excellent. Producer Gas Fired Furnaces. By OSKAR NAGEL. Large 8vo., cloth, 184 pages. New York: Published by the author. Price, $2 .oo net. All of Mr. Nagel’s works have the merit of covering subjects not otherwise specifically treated in the English language. The work under consideration is made up of some ten chapters and a n appendix, in which are to be found descriptions of all
