January 27, 19 16] 



NATURE 



58) 



it consists of Mr. Runciman, the President, of his 

 Grace the Archbishop of Canterbury, of the 

 Speaker of the House of Commons, and of the 

 Speaker of the Irish House of Commons. On the 

 20th inst., Mr. Lynch asked the President whether 

 it would not be desirable "to reconstitute the 

 Board so that it may contain two men of recog- 

 nised ability in the industrial world, and two men 

 of science, noted for their knowledge of technical 

 education and interested in the problem of provid- 

 ing for its application to industrial development? " 

 Mr. Pretyman said there were grave objections 

 to any scheme which would divide the responsi- 

 bility of the President among the members of a 

 board, and that the object was attained by the 

 development of advisory committees of experts 

 whom the President can consult. But what if you 

 have a President unable to understand their recom- 

 mendations? We have only to remember the 

 ghastly blunder committed at the beginning of the 

 war in the non-recognition that cotton and fats are 

 potential ammunition. We cannot afford to make 

 any more blunders, and it is a good maxim that 

 when a man has blundered once, he should not 

 have any further chance of endangering the 

 Empire. This is a time for drastic action ; how 

 can it be achieved? Can our Dominions exert 

 pressure? There is no means by which public 

 opinion can manifest itself except by a general 

 election, and that is denied us. But time is pass- 

 ing, and the enemy is gaining ground. Must we 

 still "wait and see"? 



William Ramsay. 



PHYSICS FOR ENGINEERING STUDENTS. 

 (i) Introduction to Magnetism and Electricity. 



By E. W. E. Kempson. Pp. viii + 240. 



(London : Edward Arnold, 1915.) Price 3s. 



(2) A First Course in Engineering Science. Bj 

 P. J. Haler and A. H. Stuart. Pp. viii + 191. 

 (London: University Tutorial Press, Ltd., 

 191 5.) Price 2s. 6d. 



(3) Practical Shop Mechanics and Mathematics. 

 By J. F. Johnson. Pp. ix + 130. (New York: 

 J. Wiley and Sons, Inc. ; London : Chapman 

 and Hall, Ltd., 191 5.) Price 45. 6d. net. 



(4) Continuous and Alternating Current Machinery 

 Problems. By Prof. W. T. Ryan. Pp. vii-r 

 2,7- (New York : J. Wiley and Sons, Inc. ; 

 London: Chapman and Hall, Ltd., 1915.) 

 Price 2s. 6d. net. 



(i) A /T R. KEMPSON 'S book on magnetism 



IVX and electricity is based on the course 



given to the science forms in the Upper School 



at Rugby. The ground covered is fairly exten- 



NO. 2413, VOL. 96] 



sive, and the matter is dealt with more from the 



experimental side than the mathematical. The 



phenomena of induced currents, however, are not 



touched. Part of the author's aim in writing 



the book has been to bring out clearly the con- 



, necting link between static and current electricity. 



j He contends that the impression left on the 



j average pupil after perusal of most text-books is 



that static and current electricity are separate and 



I distinct phenomena. The only link usually 



I attempted is the experiment with the voltaic cell 



and condensing electroscope. In our opinion, the 



chief advantage of the old method is cheapness ; 



the method suggested by the author necessitates 



the provision of much more expensive apparatus 



than is usually found in school laboratories, viz., 



electrostatic voltmeters and condensers. 



The author states in his preface that the rela- 

 tively large and varying capacity of static volt- 

 meters is likely to give trouble if not borne in 

 mind. We entirely agree, and would add that it 

 is scarcely possible for the pupil at this stage to 

 follow the method by which the teacher calculates 

 size of condensers, speed of rotating commutators, 

 etc., necessary to ensure success of the experi- 

 ments suggested. In the section on magnetism, 

 p. II, we should prefer a more precise definition 

 of unit magnetic pole ; the medium in which the 

 poles are placed should be stated ; and we object 

 to the words in brackets in the same paragraph, 

 thus: " I dyne (1/981 of a gramme's weight)." 

 The book is provided with a large selection of 

 numerical exercises to which answers are sup- 

 plied. The student working through this book 

 will have familiarised himself-with many electrical 

 testing instruments. 



(2) Haler and Stuart's "First Course in En- 

 gineering Science " covers the ground suggested 

 by the Board of Education in its " Memorandum 

 on the Teaching of Engineering in Evening Tech- 

 nical Schools." The book is divided into two 

 parts. Part i. deals with measuring instruments, 

 experimental mechanics, and the testing of 

 materials. Simple experiments are described 

 illustrating the principles, and the apparatus 

 needed is such as can be easily constructed in the 

 school workshop. The text is illustrated by a 

 good selection of clear diagrams, and each chapter 

 is provided with a set of numerical exercises. The 

 second part of the book is devoted to the ele- 

 mentary principles of heat, and includes chapters 

 on the steam engine, indicator diagram, and the 

 use of steam tables. On p. 118 there is an error 

 in the formula given for the expansion coefficient 

 of a liquid by the specific gravity bottle ; the 

 quantity in the denominator should be the weight 

 of liquid filling the lx)ttle at the higher tempera- 



