Mat 12, 1916] 



SCIENCE 



687 



been used by me and has proved very satis- 

 factory. 



In a foot-cylinder with a ground top is 

 placed a smaller graduated cylinder contain- 

 ing the solution. The larger cylinder contains 

 sufficient solvent to reach nearly to the top of 

 the smaller one. The system is enclosed by a 

 ground-glass vaseliued plate covering the outer 

 cylinder. Gradually the volume of the solu- 

 tion increases and the change in volume can 

 be accurately followed and recorded. 



In an experiment which lasted two months 

 the total change in a nearly saturated salt 

 solution was from 5.8 c.c. to 6.6 c.c, or nearly 

 14 per cent. This is to be repeated for verifi- 

 cation, and other solutions of various solvents 

 and solutes studied. 



James H. Eansom 



PUEDUE UNIVERSITT, 



March 25, 1916 



SCIENTIFIC BOOKS 



Engineering as a Career. A series of papers 

 by eminent engineers, edited by F. H. 

 ISTewell and C. E. Drayer. 

 This book of 214 pages is made up of selec- 

 tions from the writings of different engineers 

 so chosen as to embrace a broad field of prac- 

 tise. It is a mosaic presenting attractive 

 fragments from the work of active leaders in 

 steel-making, in manufacturing, in marine 

 engineering, in railroad operation and mainte- 

 nance, in municipal administration, in indus- 

 trial management, in architecture, in mining 

 and metallurgical work, and in other equally 

 interesting and important lines of activity. 

 The book opens with a general discussion of 

 the engineer and his profession by Mr. Albert 

 J. Himes. Mr. "Worcester E. Warner speaks 

 especially from the standpoint of the mechan- 

 ical engineer, Mr. A. "W. Johnston from that 

 of the railway engineer, and Mr. Chester W. 

 Larner from that of the hydraulic engineer. 

 Altogether twenty-two selections are presented. 

 They make an impressive picture drawn by 

 men of experience, concerning the opportu- 

 nities offered to and the attributes of char- 

 acter required by one who seeks a career as an 

 engineer. 



The book will interest parents, ambitious for 

 the success of their growing sons, who are ap- 

 proaching the question as to whether their sons 

 shall go to college, and if so, whether they 

 shall seek to become engineers ; it will interest 

 multitudes of high-school boys, who are waver- 

 ing between the call of business and that of the 

 technical or professional school; and it will 

 interest engineers who enjoy any well-con- 

 sidered formulated statement which seeks to 

 set forth broad views of the engineer's prob- 

 lem and of the place which he must assume in 

 society. But it is especially for the boy and 

 for the parents of boys. 



The editing has been a labor of love, the 

 work having been done by Mr. C. E. Drayer, 

 secretary and later president of the Cleveland 

 Engineering Society, and by Professor F. H. 

 Newell, head of the department of civil engi- 

 neering of the University of Illinois, who for 

 twenty-five years served the government in an 

 engineering capacity, principally as chief 

 engineer and later as director of the United 

 States Reclamation Service which has been 

 responsible for the building of great reser- 

 voirs and irrigation canals throughout the arid 

 west. W. F. M. Goss 



University of Illinois 



The Bare Earths. By S. I. Levy, B.A. 

 (Cantab.), B.Sc. (Lond.), A.I.C., Late 

 Hutchinson Research Student of St. John's 

 College, Cambridge. Longmans, Green and 

 Company. With illustrations. Pp. 359. ITet, 

 $3.00. 



This is the first book published in English 

 that attempts to give a fairly comprehensive 

 account of the rare-earth group, and the mag- 

 nitude of the task has resulted in a volume of 

 considerable size. 



An introduction written by Sir William 

 Crookes, himself a master in this field of re- 

 search, does much at the outset to give the 

 book standing. 



The work is divided into three parts : I. 

 Occurrence of the Rare Earths ; H. Chemistry 

 of the Elements; ILL Technology of the Ele- 

 ments. The author has included zirconium 

 and titanium among the elements treated, be- 

 cause of their occurrence in rare-earth min- 



