August 24, 19 16] 



NATURE 



519 



if the properties of steel with the carbon content 

 nd the influence of nickel, mang-anese, vanadium, 

 hromium, etc. The author gives a general theory 

 if the heat treatment of steels which is original, 

 nd which, the author believes, throws much light 

 in practical problems and is certainly interest- 

 \^. Cements are shortly treated in a final 

 hapter. 



Although some defects, probably due to haste, 

 lave been indicated, this treatise is really a good 

 ne and can be recommended to practical engi- 

 eers as containing information not easily acces- 

 ible elsewhere. Perhaps the fault of being rather 

 DO positive in accepting conclusions not fullv 

 stablished is one to which a teacher of students 

 - specially liable. 



SOUND AXALYSIS. 



he Science of Musical Sounds. By Prof. D. C. 

 Miller. Pp. viii + 286. (New' York : The 

 Macmillan Company ; London : Macmillan and 



I Co., Ltd., 1916.) Price 105. 6d. net. 



r TNDER the above title the author has pre- 

 1^ sented in book form a series of eight 

 ;ctures on sound analysis delivered at the Lowell 

 istitute in Januar\- and February, 1914. A 

 )urse of scientific lectures designed for the 

 eneral public must consist in large part of 

 ementary and well-known material, selected and 

 iranged to develop the principal line of thought, 

 'ut it is expected that lectures under the auspices 

 j the Lowell Institute, however elementary their 

 iundation, will present the most recent progress 

 ! the science in question. It is further expected 

 ";at such lectures will be accompanied by experi- 

 jents and illustrations to the greatest possible 

 'gree. _ 



Thus, in the present work, we find that mathe- 

 matical treatment is almost absent ; the few equa- 

 ins that occur throughout its pages might be 

 «llected so as to appear at a single opening of 

 ^e book. On the other hand, the figures number 

 larly two hundred, many of them being photo- 

 japhic reproductions of vibration curves or 

 Jparatus. These serve to indicate the wealth of 

 ti demonstrative material by which the lectures 

 \re illustrated. 



The first lecture deals with sound-waves, simple 

 Irmonic motion, noise, and tone ; the second with 

 t? characteristics of tones. The third lecture is 

 ticerned with methods of recording and photo- 

 J:iphing sound-waves, and includes a description 

 <^ the author's special recorder called the phono- 

 cfe. Lectures four and five develop the analysis 

 aJ synthesis of compound harmonic curves, and 

 tat the influence of horn and diaphragm. The 

 sth and seventh lectures are concerned with the 

 ^le qualities of musical instruments and the 

 ' '^''^al characteristics of the vowels. The eighth 

 treats the problems of the synthesis of 



vis and words, and concludes with remarks on 

 " relations of the art and science of music. 



he work includes a valuable bibliographic 

 XO. 2443, VOL. 97] 



appendix of more than a hundred references. The 

 type and illustrations are large and clear, and the 

 book should prove welcome to a wide circle of 

 readers and find an honoured place in every 

 acoustical library. E. H. B. 



OUR BOOKSHELF. 



Studies in Blood-Pressure, Physiological and 

 Clinical. By Dr. George Oliver. Edited by 

 Dr. VV. D. Halliburton. Pp. xxiii + 240. Third 

 edition. (London: H. K. Lewis and Co., Ltd., 

 1916.) Price 75. 6d. net. 

 This posthumous edition opens with an obituary 

 notice of the author by Prof. Halliburton, who has 

 undertaken the duties of editor as a " true labour 

 of affection and respect." This latest edition em- 

 bodies the chief advances in the clinical investiga- 

 tion of blood-pressure, and contains a description 

 of the author's own instruments for testing the 

 pressure. It is argued that the condition of the 

 vessel wall does not seriously interfere with cor- 

 rect readings ; hypertonicity, which produces the 

 greatest resistance, can be counteracted by 

 repeated compression or massage. It is note- 

 worthy that occupations involving anxiety, worry, 

 and nerve strain tend to augment blood-pressure. 

 It is pointed out that "pulse-pressure" (the dif- 

 ference between the systolic and the diastolic pres- 

 sure) tends to increase after the age of forty. The 

 suggestion that arterio-sclerosis may be so ad- 

 vanced as to cause an entire abolition of vaso- 

 motor control is open to question ; for it is diflScult 

 to see how life could be carried on under such con- 

 ditions. The author holds that widespread 

 thickening of the arterial wall suffices to maintain 

 long-continued high pressure, and that there is no 

 need to postulate f>ersistent hypertonicity of the 

 arteries, which he considers physiologically 

 improbable. 



The Chemistry of the Garden: A Primer for Ama- 

 teurs and Young Gardeners. By Herbert H. 

 Cousins. Revised edition. Pp. xviii + 143. 

 (London: Macmillan and Co., Ltd., 1916.) 

 Price IS. 

 When the demand for a book is such that it needs 

 to be reprinted eight times since its first issue in 

 1898 and now calls for a revised edition, it obvi- 

 ously needs little commendation to the public for 

 whom it is written. Mr. Cousins 's volume con- 

 tains in its 143 pages a vast amount of informa- 

 tion on the management of soil for the successful 

 production of garden crops. In the new edition 

 we notice reference to recent Rothamsted work on 

 partial sterilisation and to the shortage of potash 

 caused by the war. On the latter account the 

 gardener need not worry, as any moderately good 

 garden soil has ample reserves of potash, which 

 can be made available as plant food by suitable 

 treatment. We do not agree with two of the 

 author's remarks on dung. He says that "no 

 analysis is of much value " : on the contrary, ex- 

 perience at RotJiamsted and elsewhere shows that 



