August 2, 1912] 



SCIENCE 



149 



physical basis and the mechanical theory of 

 aviation, and contains many useful and con- 

 cisely solved problems that will appeal to 

 amateurs and professionals devoted to the 

 practical study of the aeroplane. A special 

 commendation of the work is that it was 

 awarded the Monthyon prize in 1911 by the 

 French Academy of Sciences. 



A. F. Zahm 



Smohe — A Study of Town Air. By J. B. 

 Cohen and A. G. Ruston. New York, Long- 

 mans, Green & Co. 1912. 



Among the principal disadvantages at- 

 tendant upon our modern civilization is the 

 smoke produced wherever soft coal is burned. 

 As in so many other cases, the possibility of 

 doing away with the evil rests, to a great ex- 

 tent, upon the sufficient arousal of public 

 opinion; in this instance, that there may be 

 enacted the legislative measures necessary for 

 the enforcing of the smokeless combustion of 

 soft coal. 



The means and methods of burning soft 

 coal without smoke, having been the subject 

 of numerous publications, are well known. 

 But attention to other phases of the subject, 

 which are so necessary for the enlisting of 

 public sympathy, are remarkably lacking. 



In point of fact, this little book by Cohen 

 and Euston is the first attempt to gather 

 what little information we already possess 

 along these lines into such form as to be ac- 

 cessible to and easily comprehended by the 

 general public. 



This book, therefore, takes one into a field, 

 new to the average reader, and gives him a 

 point of view different from that to which he 

 is accustomed. It is, thus, eminently worth 

 while. 



The first chapter has to do with the chemi- 

 cal composition of soot and shows why it is 

 obnoxious and injurious. Reliable figures are 

 given for the amount of soot formed from a 

 definite amount of coal burned, for the solid 

 impurities in the air-r-and for the daily soot 

 fall in various towns in England. 



The effect of smoke on vegetation is treated 

 with considerable detail and is shown in many 

 cases to be decidedly injurious. 



The effect of sulphuric acid in the air upon 

 metal work and vegetation, here gone into at 

 length, while interesting to know, is somewhat 

 out of place, as the smokeless combustion of 

 soft coal will not do away with the acid 

 emitted from our chimneys. 



The study of the diminution in the trans- 

 parency of the air and the increase in fogs 

 due to smoke forms an instructive discussion. 



The chapter on the influence of coal-smoke 

 upon health, by Dr. Ascher, is a valuable ad- 

 dition to the book, showing that, " there can 

 be little doubt that coal dust smoke and soot 

 increase the death rate from acute lung dis- 

 eases." 



Altogether it is a clear, concise and, above 

 all, trustworthy collection of data concerning 

 smoke and soot and the damage done by them. 

 R. C. Bennee 



Department of Industrial Research, 

 Universitt of Pittsburgh 



General Index to a Hand-list of the Genera 

 and Species of Birds: [Nomenclator avium 

 turn fossilium tum viventium.] Volumes I.- 

 V. Edited by W. R. Ogilvie-Grant. London : 

 Printed by order of the Trustees. Sold by 

 Longmans & Co., 39 Paternoster Row, E. C. ; 

 B. Quaritch, 11 Grafton Street, New Bond 

 Street, W.; Dulau & Co., Ltd., 37 Soho 

 Square, W. ; and at the British Museum 

 (Natural History), Cromwell Road, S. W. 

 1912. All rights reserved. 8vo. Pp. vi -|- 

 199. 



Dr. Richard Bowdler Sharpe's " Hand-list 

 of the Genera and Species of Birds " (5 vols., 

 8vo) was completed in 1909.' Although each 

 of the five volumes (except the first, indexed 

 with volume II.) was supplied with an index, 

 a general index has been prepared, under the 

 editorship of Mr. W. R. Ogilvie-Grant, Dr. 

 Sharpe's successor in charge of the ornitho- 

 logical collections in the British Museum, 

 "to supply a much-felt want." The task of 

 amalgamating the indexes to the five volumes 

 was done mainly by Mr. Grant's chief assist- 

 ant, Mr. Thomas Wells. We are told in the 



'Eeviewed in Science, N. S., Vol. XXXI., No. 

 790, pp. 265-267, February 18, 1910. 



