528 



NATURE 



[September 29, 1904 



The physiological effects produced by the radium 

 salts are described in considerable detail, and the 

 author looks for important applications in this direc- 

 tion. Thus, whilst the book is addressed to all those 

 who are likelv to be interested in the subject, especial 

 care has been taken to state in detail those observ- 

 ations that are of importance to students of medicine 

 and surgerv. The developments that have taken place 

 in recent years in the application of physical methods 

 to the cure of disease justify the argument, which 

 forms the main part of Prof. d'Arsonval's preface, that 

 the study of physics should occupy an important place 

 in a medical curriculum. 

 Chemical Laboratories for Schools. By D. S. 



Macnair, Ph.D., B.Sc. Pp. 24. (London: George 



Bell and Sons, 1904.) Price 6d. 

 On the title-page of this little pamphlet are the words : 

 " Hints to teachers as to the method of planning and 

 fitting-up a school laboratory and of conducting' a 

 school course in chemistry." As the term "school 

 laboratory " is extremely vague, each school or group 

 of schools nowadays having a definite place in an 

 organised system of education, some indication of the 

 class of teacher to which the author wishes to appeal 

 would have been advisable. Apparently the instruc- 

 tion is to be essentially of an elementary nature, and 

 judging by the numerous suggestions regarding 

 balances, weights, &c., weighing operations occupy an 

 important place in the work. 



The chief features and fittings of the laboratory are 

 briefly dealt with in a simple manner. One notices 

 that several dimensions, such as width of benches, 

 height of bench-shelves, &c., are somewhat less than 

 those usually adopted. More information might have 

 been given regarding inexpensive materials suitable 

 for pipes and other surfaces exposed to chemicals and 

 fumes. For drain-pipes, fireclay or glass-lined iron is 

 suggested ; the former is seldom employed, as stone- 

 ware is found to be less porous, and on iron a coating 

 of Dr. Angus Smith's mixture is generally preferred 

 to a hard, brittle lining of glass. 



A plan is given of a laboratory for twenty pupils : 

 it is probably from an existing building, but to place 

 17-foot benches with one end against the wall is not 

 an idea! arrangement, and another side-window 

 appears desirable ; continuous desks would be cheaper 

 and more convenient than dual desks arranged en bloc. 



Much admirable advice is given regarding the 

 management of practical classes. Finally, considerable 

 space is devoted to a carefully compiled list of the 

 apparatus and chemicals required for a class of twenty 

 pupils ; each piece of apparatus is approximately priced, 

 but the allowance for some items is liberal. 



After all, the contents of this pamphlet seem more 

 suitable to be included in the author's " Introduction 

 to Chemistry " than for separate publication, even at 

 the low price of sixpence. 

 Photo Printing. By Hector Maclean, F.R.P.S. 



Pp. 100. (London : L. Upcott Gill, 1904.) Price 



js. net. 

 This is a second and revised edition of the author's 

 " Popular Photographic Printing Processes," and 

 forms a practical guide to the use of the leading kinds 

 of the so-called printing-out papers, as well as bromide 

 papers, platinum papers, and carbon tissues. We 

 notice that no reference is made to " ozotype," though 

 this is a carbon process that has been growing in favour 

 for some years, and the materials for its practice are 

 supplied commercially. The volume is what it claims 

 to be, namely, a practical guide to the use of com- 

 mercial papers, and a condensed price-list of the goods 

 of the principal makers is added to each chapter. It 

 may be safely recommended to those who wish to print 

 by the processes described, for the author is himself a 



NO. 1822, VOL. 70] 



practical worker, and has evidently bestowed consider- 

 able care on the collection of the information that he 

 gives. Deviations from strictly practical directions are 

 rare and generally unfortunate, if not unintelligible. 

 These are a few details to which we would take 

 exception. The expression " half the foregoing 

 temperature " may convey the meaning intended, but 

 it is incorrect. The use of " photo " in the title 

 as a separate word instead of as a prefix is un- 

 necessary and objectionable. The statement that 

 " gelatino-chloride prints may be completely washed in 

 ten minutes, provided " . . ., &c., is set down as a 

 fact, though we think the evidence is rather against 

 it so far as practical work is concerned. Much less 

 are we prepared to accept the statement that three 

 changes of water, allowing one ounce in each bath 

 for each quarter-plate print, will serve to free the prints 

 " as completely as possible from ' hypo.' " The 

 classification of platinum printing as a " partly print 

 out " process is an illustration of the purely 

 " practical " character of the work. 

 CEuvres scientifiques de L. Loreiiz. Edited and 



annotated by H. Valentiner. Vol. ii. Second 



Fascicule. Pp. xxii + 319-583 ; with portrait. 



(Copenhagen : Lehmann and Stage, 1904.) 

 This concluding fraction of the papers of Lorenz is 

 prefaced with an interesting critical account of his 

 life and works. We see the young Lorenz largely 

 self-taught, preferring to work out problems in- 

 dependentlv, although the result was usually to find 

 out that tliey had been solved long before, it was in 

 this laborious way that his mathematical gifts were de- 

 veloped. Owing to indifference to the usual courses 

 of instruction, there was little sympathy between him 

 and his teachers, and he left the Copenhagen Poly- 

 technic without distinction. Be that as it may, by 

 the year 1887 he had become a Councillor of State, and 

 had received the honorary degree of Doctor of Philo- 

 sophy of the LIniversity of Upsala. 



Lorenz's scientific works are, in the main, on mathe- 

 matical physics — sometimes leaning to the mathe- 

 matical side, sometimes to the physical side. The 

 editor of the present collection is alive to the lack of 

 lucidity which characterises many of these. This is 

 especially so when no experiments are forthcoming by 

 which the results obtained can be tested. 



The best known of his papers have appeared in pre- 

 ceding fascicules. The present one contains those of 

 more mathematical interest. Of these the most im- 

 portant is probably one on the development of arbitrary 

 functions by means of given functions, these being the 

 functions of Bessel. Other memoirs are on the com- 

 pensation of errors of observation, and analytical 

 researches on the number of prime numbers. Lorenz's 

 genius was, however, essentially physical ; and 

 although many of his mathematical conclusions are 

 valid, they have been reached by insight more than 

 by the application of logic such as a mathematiciarr 

 demands. 



A portrait is presented with this instalment of the 

 collection. 

 Botany Rambles. Part iii. In the Autumn. By 



Ella Thomson. Pp. 253 — 377. (London : Horace 



Marshall and Son, 1904.) Price is. 

 This is the third of a series of simple books in which 

 the parts and functions of common wild plants are 

 described for young readers. The present book is con- 

 cerned chiefly with seeds and the means by which 

 they are dispersed. Children who read the pages 

 will have their attention directed to many points 

 commonly overlooked, and if they test the statements 

 by personal observation and practical study — as the)'' 

 are advised to do — they will be given both knowledge 

 and pleasure. 



