June 17, 1909] 



NA TURE 



467 



TXcalhcr Review,, and the method was referred to by Dr. 

 Shaw at the British Association meeting of 1907, who 

 explained that it " depends upon the comparison of the 

 actual winds, as recorded on the map, with ideal or normal 

 winds as computed from the distance apart of the con- 

 secutive isobars." Prof. Brunhes discusses at great length 

 both the rules and the objections th^t have been raised 

 against them. He thinks the principal questions now 

 are : — (i) whether the method of forecasting, which in the 

 hands of M. Guilbert gives such surprising results, can 

 be formulated in a way which may obviate objections to 

 his exposition ; and {2) whether the principles can be so 

 enunciated that other meteorologists may attain the same 

 success. To the first question he gives a decided 

 aflfirmative, but to the second the reply is more reserved ; 

 the publication of the work, which has been urged by 

 M. Tcisserenc de Bort and himself, is an effort to hasten 

 ihe solution of these questions. 



We have received a new catalogue of physical and 

 electrical instruments, balances, &c., from Messrs. W. G. 

 Pye and Co., of Granta Works, Cambridge. We note that 

 a considerable number of pieces of apparatus have been 

 designed by Mr. G. F. C. Searle, F.R.S., of Cambridge. 

 This kind of cooperation between the maker and user of 

 scientific apparatus is much needed', and will, we believe, 

 result in a great improvement in the utility and accuracy 

 of the instruments made in this country. 



The question whether intermolecular radiation would 

 account for any appreciable fraction of the heat trans- 

 mitted through a metal owing to temperature differences 

 existent in it has often been discussed. Several years ago 

 Riecke showed that the part contributed by radiation must 

 be excessively small. His calculations were, however, 

 based on an equation given first by Sampson and after- 

 wards by Schuster, which Konigsberger showed was not 

 accurate. In the Physikalische Zcitschrift for May 15 

 Dr. M. Reinganum takes up the question again, and, 

 basing his investigation on the radiation work of Planck 

 and on the law that the intensity of radiation in a medium 

 of index of refraction 11 is n" times that in the ether in 

 equilibrium with it, he arrives at the conclusion that in 

 silver and in zinc radiation will not account for more than 

 one-millionth part of the heat transmitted. In alloys it is 

 still far below the order of magnitude of the conduction. 

 In all electron theories of conduction it may therefore be 

 entirely neglected. 



E.ASEMENT curves form the subject of an interesting 

 article, by Prof. R. H. Smith, in the Engineer for June 4. 

 The term " easement " indicates a curve which can be 

 turned without damaging collision, without the fury of 

 whirlpool motion in fluids or of hard knocks between solid 

 members. Within elastic limits, a heavy stress steadily 

 maintained does no harm. The damaging intensity of a 

 blow is proportional to the time rate at which the stress 

 increases. When the stress is produced by curvature in 

 the motion path, the author shows that the intensity of 

 the radial shock is proportional to the product of the 

 cube of the velocity and the rate of change of the curvature 

 with respect to length measured along the path. In pro- 

 portion as the cube of the velocity is high, the rate of 

 change of curvature should be low. Hence the import- 

 ance of examining different forms of easement curves in 

 respect of this purely geometric characteristic. The author 

 discusses mathematically curves shaped to the equation 

 y = Kx'", where m is any index. The time rate of increase 

 of radial stress should be little or nothing at first, and 

 should gradually increase up to the unavoidable amount. 



.NO, 2068, VOL. 80] 



It starts with zero if m be anything greater than 3, but" 

 the most satisfactory result is not obtained with m lets 

 than 4. Of all this class of easement curves, the bi- 

 quadratic parabola is the best. 



In several notices and reviews it has been pointed out 

 that the experimental study of flow of air past resisting 

 bodies not only was of importance in connection with 

 aviation, but might also have valuable applications tO' 

 the problem of dust formation in the wake of motor- 

 cars. .'\t that time it was not known to the writer of the 

 notices that the matter was receiving attention. A paper 

 by Mr. W. R. Cooper, read before the Royal Automobile 

 Club on May 18, shows that automobilists have not been, 

 so behindhand in appreciating scientific methods as was 

 supposed. Indeed, experiments involving photography of 

 dust clouds were described in the Automobile Club Journal- 

 so far back as December, 1905, and an account of them 

 appeared in N.^ture. Mr. Cooper now describes a record- 

 ing apparatus with which he has studied the direction of 

 the stream lines in the neighbourhood of the car. It- 

 consists essentially of a small vane at the end of a bamboo • 

 rod, which can be moved about behind or in front of the 

 car, the vane being connected by pulleys with a pointer- 

 inside the car. An apparatus for measuring air pressures 

 is also described. Mr. Cooper is to be congratulated on 

 Ihe progress he has made, and though there are still', 

 many difficulties to be overcome, there is no doubt about 

 the practical value of these researches. 



.An -American edition of Mr. R. C. Punnett's little book 

 on Mendelism has been published by the Wilshire Book 

 Co., of New York. The new edition is provided with a 

 preface by Mr. Gaylord Wilshire, in which he deals with 1 

 the sociological significance of the Mendelian theory. 



Messrs. M.^cmillan and Co., Ltd., now publish the 

 well-known book by the late Prof. A. Milnes Marshall, 

 F.R.S., on " The Frog." The volume, which, it will be 

 remembered, is an introduction to anatomy, histology, and ' 

 embryology, has been edited by Dr. F. W. Gamble, . 

 F.R.S., and has now reached its tenth edition. 



A CAT.4LOGUE of books on astronomy, mathematics, and 

 physics, consisting mainly of important works purchased 

 recently from several private libraries, has just been issued 

 by Mr. Bernard Quaritch, 11 Grafton Street, New Bond 

 Street. The price of the catalogue is one shilling. 



During the seventh International Congress of Applied' 

 Chemistry, held recently in London, photographs of four- 

 teen groups of the various sections were taken by the 

 Dover Street Studios. Prints of these groups have been 

 sent to us, and one of them, reproduced in a reduced form, 

 accompanies the general article upon the scientific proceed- 

 ings of the congress which appears elsewhere in this issue. 

 We are informed that the photographs are to be published 

 in complete album form at the price of four guineas, or 

 they may be had separately. 



A SECOND edition of " Sanitary Law and Practice : a 

 Handbook for Students of Public Health and Others," by 

 Prs. W. Robertson and Charles Porter, has been published 

 by the Sanftary Publishing Co., Ltd. The original issue 

 of the work was reviewed in Nature of June i, 1905 (vol. 

 Ixxii., p. 97), and it is sufficient to state here that much 

 new matter has been added to the volume, and the former 

 text completely revised and in many instances re-written. 

 .Among the new sections, those on school medical inspec- 

 tion and vital statistics may be mentioned. The size of 

 the print has been reduced slightly, and the price remains 

 at los. bd. net. 



