July 28, 1910] 



NATURE 



103 



OUR BOOK SHELF. 

 Light and Sound: a Text-book for Colleges and 

 Technical Schools. By W. S. Franklin and Barry 

 Macnutt. Pp. viii + 344. (New York: The Mac- 

 millan Co.; London: Macmillan and Co., Ltd., 

 1909.) Price 5s. net. 

 In writing a text-book, an author generally chooses 

 definitely between two methods of exposition : he either 

 writes a small book, and confines his attention to the 

 most elementary parts of the subject treated of ; or 

 else he writes a more pretentious work, in which most 

 branches of the subject receive adequate attention. 



The authors of the text-book now under review have 

 followed a middle course. The fundamental principles 

 of Sound and Light are discussed with great care, 

 and numerous practical applications of these principles 

 are described ; for the explanation of complicated 

 phenomena, the student is referred to more advanced 

 text-books. The book opens with a very thoughtful 

 e.xposition of the wave theory, illustrated by reference 

 to water waves, sound waves, and waves in an elastic 

 solid ; and the subject of Light is developed wholly in 

 accordance with the wave theory. Numerous optical 

 instruments, including the standard forms of photo- 

 graphic lenses, are described and illustrated ; and a 

 clear but necessarily incomplete theory is given of the 

 defects of lenses, and their compensation. Consider- 

 able attention is devoted to the subject of photo- 

 metry and illumination ; technical students should 

 Kirefully study the chapter devoted to this part of the 

 subject. The fundamental facts of polarisation are 

 explained clearly and well. 



In connection with sound, the simple phenomena, 

 which are generally discussed in elementary text- 

 books, are dealt with concisely. A very interesting 

 chapter is devoted to the theory of music, and an 

 account is given of Sabine's researches on the audi- 

 bilitv of sound in rooms of various sizes ; here, once 

 more, technical students will find much to interest 

 them. Altogether the book should prove very useful. 



E. Edser. 



Kraft: das ist animalischc, mechanische, soziale 

 Energien iind deren Bedeiitung fiir die Machtentfalt- 

 ung der Staaten. By Prof. Dr. E. Reyer. Zweite 

 Auflage. Pp. xvi+471. (Leipzig: W. Engelmann, 

 1909.) Price 8 marks. 

 Soziale Mdchte : als Erganzung der Arbeit iiber 

 "Kraft." Same author and publisher. Pp. 11 1 

 (1908.) Price 1.60 marks. 

 The first edition of Dr. Reyer's " Kraft " was noticed 

 at length in Nature (vol. Ixxviii., p. 660) shortly after 

 Dublication, and to that notice we must refer the 

 "•eader for details as to the scope of the work. The 

 present, second, edition has been somewhat extended, 

 but does not appear to have been rewritten to any 

 considerable extent, and it retains all the faults of the 

 earlier issue. The same lack of orderly arrangement 

 distracts the reader, the same lack of references ren- 

 ders the work almost valueless to the serious student, 

 and the same absence of " the scales and the names 

 of the plotted quantities " continues to characterise 

 the diagrams. The bibliography remains remarkable 

 both for its inclusions and its omissions, and it s''' 

 contains even the two remarkable entries to which 

 attention was directed in the notice of the first edition 

 — " Produktion and consum. of timbre in forein 

 countries (blue book)," and "Statesman's vearbook. 

 Statist. Abstracts (mit statistischen Tabellen) "—the 

 latter entry apparentlv confusing the "Statesman's 

 Yearbook" with the " Statisticaf Abstracts." 



The title of the second volume named above is, at 

 the present date, misleading. When first published— 

 the title-page bears the date igoS, although the cover 



NO. 2126, VOL. 84] 



is dated 1909 — the title may have been correct, for the 

 volume is apparently a supplement to the first edition 

 of "Kraft." It is not supplementary to the second 

 edition, but a mere reprint of pp. 339-447. In these 

 pages Dr. Reyer considers such matters as migration, 

 wages and conditions of labour, the struggle for better 

 conditions of life, personal energies and their contri- 

 butions to civilisation. 



Notes on the Electric Smelting of Iron and Steel. 



By Dr. W. F. Smeeth. Bulletin No. 5, Mysore 



Geological Department. Pp. vii4-i36; maps. 



(Bangalore : Government Press, 1909.) Price 2 



rupees. 

 Electric steel melting and refining is now an estab- 

 lished industry, but the electric smelting of pig-iron 

 from the ore has recently entered on a new phase, 

 namely, the commercially successful. The writer has 

 had given to him, in confidence, figures of costs in 

 connection with an electric furnace making charcoal 

 pig-iron, with permission to mention the facts with- 

 out the figures. It is clear that under conditions 

 where the fuel is charcoal, and is becoming increas- 

 ingly scarce and expensive, so far as can be judged 

 from experience with a furnace of commercial size 

 working for months, the smelting of high-grade ore 

 into charcoal pig-iron is proving profitable. Only the 

 balance sheet is a safe guide, but this test is about 

 to be applied on quite a large scale. 



The present bulletin embodies the technical portions 

 of a report prepared by Dr. Smeeth at the request of 

 the Government of the Maharajah of Mysore. A short 

 description of the Stassano furnace is given, and de- 

 tails of several charges of steel made in the furnace 

 in 1908 from pig-iron and scrap with the usual addi- 

 tions. Chapter iii. contains details of an attempt to 

 make high-quality steel, carbon o'2 to o'3 per cent., 

 in the Stassano furnace from very impure ore, a 

 serious task. The author calculates that to produce 

 steel from the ore, the electric furnace will require 

 only about one-third of the amount of charcoal neces- 

 sary for smelting with fuel furnaces, but (p. 45) "The 

 sulphur is high (o'24 per cent.) and renders the steel 

 quite unfit for use." Trial C showed a better analysis, 

 but the mechanical test given by the steel was not 

 good. In part ii. of the bulletin, materials and costs 

 at Mysore are considered, and the opinion is ex- 

 pressed that the manufacture of steel castings, steel 

 forgings, railway tyres, and even rails could be 

 carried on successfully there, and at a profit. The 

 author evidently has courage. A folding geological 

 map of the Bababudan iron-ore area is enclosed in a 

 pocket on the cover. A. Mc.W. 



Psychism. By M. Hume. Pp. 157. (London and 

 Felling-on-Tyne : Walter Scott Publishing Co., 

 Ltd., n.d.) Price 2S. bd. net. 

 Mrs. Hume begins with a curious and rather inco- 

 herent theory respecting the "Trinity of Man" 

 (Matter, Intelligence, Force; or, in another aspect, 

 Reason, Intuition, and Soul), but she becomes de- 

 cidedly interesting when she proceeds to describe her 

 own experiences. These have been visions, dreams, 

 or other phenomena by which a warning of an im- 

 pending event — e.g. the death of a friend at a dis- 

 tance — has been conveyed. The agency is believed 

 by the author to be her own subconscious self, which 

 possesses clairvoyant and other powers. The theory 

 propounded closely approaches that of the leading in- 

 vestigators in these domains, but we would suggest 

 that the terminology of Myers is preferable to that 

 of T. J. Hudson, who, moreover, is an unsafe guide, 

 being apt to rear a large structure of theory on a 

 small or insecure foundation of fact. The book is 

 well written and nicely got up. J. A. H. 



