850 



NATURE 



[February 24, 192 1 



(sporocarps of Marsilea sp.). — Prof. A. V. Hill : The 

 purpose of physiology. As the handmaid of medicine, 

 the task of physiology lies in the discovery and state- 

 ment of the "normal" as distinguished from the 

 "abnormal." As a pure science it is privileged to 

 explore the mechanisms underlying the phenomena of 

 life by any and every means provided by scientific 

 progress. As an applied science, in co-operation with 

 psychology, it deals viith such questions as the condi- 

 tions of maintenance of the "normal," the standards 

 of fitness, inental, moral, and physical, and the 

 biological factors in the economic or social system. 

 Progress may be expected in the regions where physio- 

 logy verges on the other, especially on the exact, 

 sciences, while the stimulus to the applications of 

 physiology appears on the borders of medicine, sport 

 and physical training, industrial fatigue, sociology 

 or economics. 



December 9.^ — Mr. R. L. Taylor, vice-president, 

 in the chair. — Prof. T. E. Peet : Ancient Egyptian 

 mathematics. Known to us chiefly from the Rhind 

 papyrus in the British Museum, Egyptian mathe- 

 matics is not a speculative science, but one purely prac- 

 tical in scope. The author dealt with the cumbrous 

 notation ; the use only of fractions the numerator of 

 which was unity (with the one exception of two- 

 thirds); tables for multiplication bv 2 only, and 

 with division by 2 only, larger divisions being done 

 by trial. Problems such as the division of food, the 

 measurement of areas, the exchange of loaves of 

 various sizes and of jugs of beer were easily accom- 

 plished. -A parallelopiped was correctly cubed, the 

 volume of a cylinder obtained, and the circle given 

 as the square of ei^ht-ninths of its diameter. The 

 existence in Egypt of a standard of rings or shatyw 

 of various metals was dealt with. 



Dublin. 



Royal Dublin Society, January 25. — Dr. F. E. Hackett 

 in the chair. — J. J. Dowling : A direct-reading ultra- 

 micrometer. The apparatus, which was exhibited in 

 operation, depends on the variation of the plate cur- 

 rent in an oscillating-valve circuit, which accompanies 

 a variation in the capacity of the oscillating circuit. 

 The sensitivity of the arrangement is very high, but 

 even under unfavourable conditions it shows remark- 

 able steadiness. Preliminary measurements show that 

 a displacement of about 2x10-' cm. is detectable 

 under ordinary working conditions, and with suitable 

 precautions very much greater sensitivity can be 

 reached. Further work in connection with the ap- 

 paratus is being carried out. — J. Reilly and W. J. 

 Hickinbottom : The distillation constant of certain 

 primary alcohols. The authors have applied their 

 method of distillation in steam to methyl, ethyl, 

 propyl, butyl, and isoamyl alcohols. Percentage of 

 alcohol is estimated from density or by oxidation. 

 Distillation constant varied with concentration. 



Edinburgh. 

 Royal Society, January 10. — Prof. F. O. Bower, 

 president, in the chair. — The late Dr. John Aitken : 

 Thermometer screens. This paper was left in manu- 

 script by Dr. Aitken, and was completed a few- 

 days before his death. It gives a new series of experi- 

 ments summing up his results communicated from 

 time to time during the last thirty years. The points 

 emphasised were (i) the inadequacy of the Stevenson 

 screen, which in sunny weather always makes the 

 enclosed thermometers read too high ; (2) the uncer- 

 tainty of measuring the temperature of the air, which 

 cannot be other than a time-average varving with the 



NO. 2678, VOL. 106] 



thermometer used; and (3) the description ot a new 

 auiipie lorm ot screen \vnicn satisues ail practical 

 neeas. — Jr'roi. V\ . reouie : ine avoiaante ol relauvii) 

 which is not ot Galileo-Newtonian type. It is the 

 mm of natural philosopny to nn<i more and more 

 inclusive laws clescribiiig the course ot inanimatt: 

 Nature. Examples are the conservation of matter 

 and energy, ine law ot least time, stationary action, 

 varying action, and Einstein's recent aevelopnient 01 

 relativity. Iheir chiet value lies in the tact chat they 

 give results which are independent ol tne particular 

 mechanism involved. All actions wnich seem to occur 

 at a distance take place, according 10 Newton, 

 through a medium or aether. It is sometimes asserteU 

 tnat in consequence of the results of the principle 

 ol relativity the ather is non-existent; but me natural 

 pnilosopher is entitled to claim that any suctt deduc- 

 tion from a theory which obtains its results indepen- 

 dently of the mechanism involved can have no validity. 

 Within its range the principle is of great value and 

 constitutes the greatest advance made in connection 

 with general laws since the introduction of itie prin- 

 ciples ot action. These general laws can only be 

 judged by the coincidence of their conclusions with 

 observation. In this respect Einstein's principle stood 

 successfully the test of two facts of observation, one 

 of which was a prediction. In connection with a 

 third the result is doubtful. It is, therefore, desir- 

 able to consider possible modifications of the basis 

 to which the principle is applied. The only one now 

 possible seems to be that connected with the postulate 

 Ltiat light is propagated through a uniform arther 

 regarded as at rest in space. If light is propagated 

 through aethereal strain-forms associated with the 

 atoms and moving with them, the aether itself may 

 be at rest, but this experimental foundation for the 

 recent extensions of relativity would disappear. On 

 the other hand, in this case a positive result should 

 be given by the Michelson-Morley experiment if made 

 with light from a star moving rapidly to or from 

 the earth. The paper concluded with a discussion of 

 the possibility of a mechanical foundation of this 

 view in an extension of Osborne Reynolds's theory 

 of a granular aether. — I^'. Unwin : The transverse 

 galvanomagnetic and thermomagnetic effects in 

 several metals. This investigation into these minute 

 effects gave results which were compared with cer- 

 tain conclusions derived by Livens from the modern 

 electron theory. The agreement was .satisfactorv as 

 regards the ratios of the effects, but not as regards 

 their magnitudes. — P. Humbert : The confluent hyper- 

 geometrical functions of two variables. 



Paris. 

 Academy of Sciences, January 31. — M. Georges 

 Lemoine in the chair. — The president announced the 

 death of M. Emile Bourquelot, member of the sec- 

 tion of chemistry. — L. Fave : Curves designed for the 

 determination of orthodromc routes. On a sheet of 

 transparent material curves are drawn representing, 

 in Mercator's projection, a series of great circles 

 cutting the equator at the extremities of a given dia- 

 meter. A second family of curves of a different 

 colour serve to measure the orthodrome distance. — 

 A. P. Dangeard : Observations of an alga cultivated 

 in the dark for eight years. Scenedesmiis acuiiis has 

 been cultivated in the absence of light since January, 

 19 13, and is as green as specimens grown in the light 

 in the ordinary way. The examination of the absorp- 

 tion spectrum of the chlorophyll shows no difference 

 between the two series. \ special culture medium 

 is required, the composition of which is given. — E. 

 Matbias, C. A. Crommelin, and H. K. Onnes : The 



