January, 1923
INDUSTRIAL A N D ENGINEERING CHEMISTRY
An Aid to Petroleum Chemists
expected. Possibly, if all the analyses used by Ralston had been plotted, the shading of one group into another might be more pronounced. Professor Parr and his associates have given us much to think of on the classification of coals. Now can some one tie their work with uses of coal and so furnish a basis for a market classification? H. FOSTER BAIN
Editor of Industrial and Engineering Chemistry: May I have a little space in your journal to emphasize one of the points made by Dr. Dean in his recent review of Brooks’s “Chemistry of the Non-benzenoid Hydrocarbons?” The fact was mentioned that the author has brought together the literature of his subject from a large number of journals, some of which are not easily accessible. This painstaking work required a great amount of effort, which was justified by the importance of the subject. The recent activity in the study of the chemistry of petroleum is leading to uses of these hydrocarbons in the preparation of substances of importance in industrial organic chemistry, and I am of the opinion that further work will eventually place petroleum in a position similar to that of coal tar as an industrial raw material. The appearance of Dr. Brooks’s book a t this time serves to facilitate markedly research in this field, and will, no doubt, inspire investigations which would never be undertaken if such an admirable review of past work were not available. The book has been of great service to both my students and myself JAMES F.NORRIS
BUREAU OF MINES WASHINGTON. D. C. November 28, 1922
Admissions to U. S. Pharmacopeia A list of additional admissions to the U. S. Pharmacopeia (10th Revision), and an additional list of U. S. P. (9th Revision) titles which it is recommended not to admit to the U. S. P. X., has recently been issued. These represent reports from the Subcommittee on Scope submitted since the first lists were made public, some months ago. Comments are invited on these recommendations and careful consideration will be given to all communications by the Special Referee Committee on Scope, which consists of the twenty-one physicians of the General Committee of Revision. Where the recommendations of the subcommittee do not meet with approval, and a protest is submitted, this should be accompanied by evidence and facts to substantiate the claim, that the referees may have all evidence before them. There are a few questions of admission and deletion not yet announced by the Subcommittee on Scope. Information concerning these lists may be obtained from, and comments should be sent to E. Fullerton Cook, Chairman, 636 So. Franklin Square, Philadelphia, Pa.
MASSACHUSETTSINSTITUTE O F TZCHNOLOOY CAMBRIDGE, MASS. Novemher 29, 1922
The Classification of Coal Editor of Industrial and Engineering Chemistry: In the October issue of the journal, Prof. S. W. Parr has brought up again this most interesting subject and has made a valuable contribution to it. There is now a widespread interest in the classification of coal, since it is being appreciated that the high prices paid for coal are in part a t least due to poor marketing and that this in turn depends in part on poor classification. A satisfactory use of classification of coals properly applied would cut down the nation’s fuel bill materially. Bridging the gap from a scientific to a market grouping of any category of goods is a long step, but no step can be taken save from a starting point and a rational scientific classification; one which- places the various coals according to natural groupings and a t the same time is easily and quickly applied would affdrd such a point. As Professor Parr shows in his brief historical introduction, the subject is not new. Horace C. Porter in 1915l gave a more detailed review of the development of ideas along this line, and following that, in the same paper, 0. C. Ralston illustrated on trilinear diagrams the groupings developed by recalculation of 3000 analyses of coals made in the government laboratories. He showed that when ultimate analyses of coals are reduced to moisture- and ash-free basis (less nitrogen and sulfur), the various ranks fall in definite areas of a trilinear diagram on which carbon, hydrogen, and oxygen contents have been plotted. He also developed “isovolatile” and “isocalorific” lines running in divergent directions across the diagram, but with such relations that the position of the coal could be predicted either from the ultimate: analysis or the calorific value and volatile content. The latter is the basis used by Professor Parr, and the difference in appearance of the diagrams is incident mainly to the use in the trilinear of lines crossing a t an obtuse angle as against those a t right angles to each other in Professor Parr’s figures. Any student of the subject will want to have both before him. The Parr diagrams are admirably clear and simple and with the coals he has plotted show good definition of groups, except between eastern and western bituminous where too much is not to be 1
Bur. Mines, Tech. Paper Sa.
99
Heat Transfer by Conduction and Convection. 11-Liquids Flowing through Pipes-Correction I n the article under the above title [THIS JOURNAL, 14 (1922), 1101] the following errors should be noted: Page 1102, 2nd col., Eq. 7, the term (pu”) should be (pu)”. Page 1102, 2nd col., E q 7 b , the term (pp)O“a should read (pu)o.a3. Page 1103, 2nd col., first line after Eq. l o a , change “which” to “Eq.
10.” Pages 1103 and 1104, Equations 96 and 9c, b should read B. Page 1104, Col. 1, the line preceding the table should read “The range of the values for water is as follows.” Page 1104, Nomenclature Table: B = Constant. Change first p to p = Intensity of absolute pressure, etc. y = Exponent. p = Absolute viscosity of liquid ut average / ; l m temperature, as Ibs. per sec. per ft. = 0.0672 times film viscosity as poises.
W. H. MCADAMS T. H. FROST MASSACHUSETTS INSTITUTE O F TECHNOLOGY CAMBRIDGE, MASS. December 13, 1922
Report of the Viscosity Committee of the Cellulose Division-Correction I n this report, published in THIS JOURNAL, 14 (1922), 1164, in the list of specifications, the eighth item should read: Temperature of solution to be maintained by a water jacket within. . . .25’ C . i 5’.
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BOSTON, MASS. December 1.3, 1922
G. J. ESSELEN, JR., Chairman
