326 



KN()\VI,KnGK. 



Aur.isT, 1912. 



it is just as necessary to assume the existenct- of " etliir " to 

 support or constitute the " lines or lield of the incepting 

 enertjy influences." It is true, we think, th.it science is not 

 concerned with the ultimate CYplanation of plienomena ; th.it 

 is the business of metaphysics. Hut \lr. Weir ou^ht not to 

 be inetaphysic'il and .intimetaphysicai in one and the same 

 breath. 



The author's .irnuments seem very far from conclusive as 

 to the supposed return of all terresti.al energy to the form of 

 a.\ial energy ; and what he terms experimental evidence not 

 infrei|nently turns out to be merely discussions of purely 

 hypothetical machines which cannot be constructed. More- 

 over, his discussion is limited to only the simplest phenomena 

 — electrical phenomena are barely touched upon, for example. 

 It is, further, hard to see how Mr. Weir's views can be 

 reconciled with the phenomenon of the increase of mass of a 

 charged particle when its velocity approaches that of light, 

 since Mr, Weir assumes as absolutely true, the law of the 

 conservation of inertia, which, using an inaccurate expression 

 (now generally discarded), he calls the law of the conservation 

 of matter. 



We by no means say that Mr. Weir's book is lacking in 



interest, but we certainly doubt whether modern physical 



theories concerning matter, energy and the ether will be 



seriouslv affected by its arguments. n r- r. 



H. S. Redgrovk. 



An Experimental Course of Physical Chemistry. — Part 

 II. Dynamical Experiments. By T.F. Spenxer, D.Sc., Ph.D. 

 256 pages. 68 illustrations. 72-in. X5-in. 

 (G. Bell & Sons. Price 3/6 net.) 

 This book forms the second part of Dr. Spencer's book 

 which has already been reviewed in " Knowledge." It is 

 an even more valuable contribution to the library of the 

 practical worker in physical chemistry. The experiments in 

 the chapter on Mass .\ction will give the student clear ideas 

 on the subject of Chemical Dynamics ; the chapter on Con- 

 ductivity of Electrolytes is thoroughly practical and useful. 

 The chapter on Dielectric Constants will be useful to the 

 advanced worker, but might have been rather more fully 

 dealt with, the descriptions being rather sketchy. The chapters 

 on Transition Temperatures and Radioactivity are also most 

 useful in a small handbook of this sort. Other chapters on 

 Transport Numbers, Electromotive Force, and Thermo- 

 chemistry are included. The book is bound to be much 

 used by students and those workers who desire to make 

 occasional physico-chemical measurements. \ r r v 



A.li.C. vj Hydrodynamics. — \W Lieut. -Col. K. Dk 

 \|[.[„\Mii., R.i:. 135 pages. 48 illustrations. Hj-in.X 5J-in. 



(E. & F. N. Spoil. Price 6/- net.) 

 This book is soniewh;it of a controversial character, and full 

 of ijuotations, criticisms and contentions. For this reason, 

 alone, the book must be an interesting volume ; but it is 

 written also by one who possesses a grasp of the subject and 

 an original insight info such matters as it deals with. It is a 

 book that recpiires reviewing very thoroughly, if it is reviewed 

 at all, and the writer prefers to bring it to the notice of 

 readers of " Knowledge " without a long discussion on 

 Hydro-dynamics, leaving it to them to form their opinion on 

 the book. The scope of the book ranges through the follow- 

 ing subjects: the resistance of liquids, viscosity, "stream- 

 lines," Stokes'-law, vortices and the sensitive flame. 



A. C. G. E. 



Tables of Logarithms. Anti-logarithms and Reciprocals. 



6 pages. 9l-in. X6-in. 



(C. & E. Layton. Price 1 -.) 



These are a clear set of well-printed logarithmic tables of 



four figures, easy to manipulate and useful for laboratory and 



statistical purposes. . r- ^ i- 



:\. U. (j. V^. 



studies in Terrestrial Magnetism. — By C. Chree, M.A., 

 F.K.S. 206 pages. 43 illustrations. 9-in.X6-in. 



(Macmillan & Co. Price 5/- net.) 



Tlie above book is one of a series of monographs, published 



by Macmillan & Co., which are intended to give the results of 



the work of their authors in a connected form, and should 



prove most valuable. Professor Chree is the first authority 



on all matters connected with terrestrial magnetism, and the 



book sets out the result of his long series of researches. As 



he states, the book deals almost entirely with facts and the 



absence of any definite theory as to the origin of magnetic 



changes is due to no lack of curiosity as to the causes of 



things. The phenomena of terrestrial magnetism are of a 



complicated nature and the book will surely be of great 



interest to all those who take an interest in physical matters; for 



they will be shown how Professor Chree has steered his way 



through a very intricate field of inquiry and collected much 



valuable information of natural processes. Physicists will be 



most interested by the chapters which deal with magnetic 



storms, and the connection between the earth's magnetism 



and sunspot activity. a /-- ^ r- 



^ • A. C. G. E. 



NOTICES. 



EDWARD SMITH.— Mr. Edward Smith, whose name was 

 mentioned in the July number of " Knowledge," page 279, 

 as the author of "The Life of Sir Joseph Banks," was in two 

 places accidently referred to under the Christian name of 

 George; a mistake which we hasten to rectify. 



THE BACTERIOLOGY OF LEPROSY.— Our reviewer, 

 in dealing with the Fourth Report of the Wellcome Research 

 Laboratories, said that no reference had been made in it to 

 the work of Beauchamp Williams on the Bacteriology of 

 Leprosy. Dr. Andrew Balfour, Director of the Laboratories, 

 writes to say that a resume of the work in cjuestion was given 

 on pages 166 and 167, under the heading of "Additional 

 Notes." Dr. Balfour adds the interesting information that it 

 is hoped at the Wellcome Research Laboratories to proceed 

 on similar lines in preparing a vaccine for the common and 

 crippling disease known as .Mycetoma or Madura Foot. 

 Captain .Archibald, who has succeeded in cultivating the 

 parasites from several species, has, in fact, put himself into 

 communication with Dr. Williams on the subject. 



DALLMEYER CAMERAS.— We have received a brief 

 list of Messrs. Dallmeyer's Cameras, amongst which we notice 

 the Carfac collapsing cameras which extend in a very simple 

 manner, can be loaded in daylight with films, and are 



British made at Messrs. Dallmeyer's factory at Willesden. 

 There is also included a special correspondent's camera which 

 was designed for newspaper men during the South .African 

 war. and which has since been improved, as well as roll film 

 cameras, a reflex for naturalists, and double extension stand 

 cameras. 



SCIENTIFIC BOOKS.— We would bring to the notice of 

 our readers Messrs. Henry Sotheran & Company's catalogue, 

 numbered 725, containing a list of more than two thousand 

 books on mathematics, chemistry, physics and astronomy.and 

 also their catalogue numbered 728, which contains a number 

 of scientific books. 



THE ISLE OF WKJHT BEE DISEASE.— The Board 

 of .Agriculture issued with the May number of its Journal 

 a supplement consisting of o\er one hundred and forty pages 

 dealing with the investigations which have been made on the 

 Isle of Wight Bee Disease in the Pathological Laboratory, 

 Cambridge. The infection may be transmitted through the 

 .igency of infected food or a living bee. Sometimes the 

 stock remains healthy and the infected bees are gradually 

 eliminated. Freciuently, however, the stock suffers severely or 

 from a mild form of the disease and succumbs. Various con- 

 ditions tend to lessen the natural resistance of the bee and no 

 permanent cure has apparently been recorded. 



