t68 Scientific Intelligence. 



existing in coal, although the distillation products have received 

 a vast amount of attention. Some attempts have been made to 

 extract the constituents with various solvents, but no definite 

 compounds have thus been isolated. Ame Pictet and Louis 

 Ramseykr have recently succeeded in extracting with benzol and 

 purifying a small amount of at least one constituent of a French 

 gas-coal. This was found to be hexahydro -fluorene, C, s H )n , a 

 hydrocarbon of the aromatic series which is slowly oxidized in 

 the air, which is gradually polymerized by heating, apparently 

 into (C 13 H 16 ) 2 , and is converted at a high temperature into fluor- 

 ene, C 13 rl 10 , a constituent of coal-tar. The hexahydro-fluorene 

 and the fluorene may be represented as follows : 



C C H, ~-C 6 H — » CJH 4 C 6 H 4 . 



^CH.^ ^CH.^ 



Berichte, xliv, 2486. n. l. w,. 



5. The Technicfd Analysis of Brass and the Non-ferrous 

 Alloys; by W. B. Price and R. K. Meade. 12mo, pp. 267. 

 New York, 1911 (John Wiley & Sons).— This book gives an 

 interesting introductory chapter in which many alloys are 

 described and their compositions are given. The main part of 

 the book is devoted to analytical methods, including electrolytic, 

 gravimetric and volumetric processes. There appears to be very 

 little in this part that is new or original, but very probably some 

 of the methods described here will be found useful to the practi- 

 cal analyst. In some cases there seems to be too little explana- 

 tion of the reasons for the step taken, if the book is to be used by 

 beginners, and not all of the explanations given are sound, as, 

 for instance, in connection with the determination of sulphur, 

 where directions are given to add jL gram of sodium carbonate 

 to a strong nitric acid solution of an alloy, it is absurdly stated 

 that this will convert any lead sulphate into carbonate. Some 

 of the descriptions of processes are decidedly bad ; for example, 

 where an entirely unnecessary operation, presumably for the sepa- 

 ration of manganese, is included as a preliminary step to the 

 determination of nickel by the dimethyl glyoxime method. 



H. L. W. 



6. Allen' 's Commercial Organic Analysis/ Fourth Edition, 

 Entirely Rewritten. Volume V. Svo, pp. 704. Philadelphia, 

 1911 (P. Blakiston's Son & Co.). — This volume, like its predeces- 

 sors, is of great interest and importance. The subjects included 

 are Tannins, Analysis of Leather, Dyes and Coloring Matters (arti- 

 ficial and natural), Analysis of Coloring Materials, Coloring Mat- 

 ters in Foods, and Inks. The contributors are W. P. Dreaper of 

 London, J. F. Hewitt of Surrey, England, W. M. Gardner of 

 Bradford, England, Albert F. Seeker of Brooklyn, N. Y., Percy 

 H. Walker of Washington, D. C, and F. Feilmann of London. 

 The section on Coloring Matters in Foods is new, and it should 

 prove useful to food analysts and others. h. l. w. 



7. Electro- Analysis ; by Edgar F. Smith. Fifth Edition, 

 Revised and Enlarged. 12 mo, pp. 332. Philadelphia, 1911 (P. 



