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NATURl:: 



[November ii, 1920 



Sir Oliver Lodge discussed the assumed necessary 

 constancy of the observed velocity of light in free 

 space as contrasted with the universally admitted con- 

 stancy of its true velocity. He contended that there 

 is no experimental evidence for the dogma that wave- 

 fronts are concentric with a travelling observer 

 initially situated at the source. The Michelson-Morley 

 experiment is consistent with such concentricity, but 

 does not necessitate it. He argued that the Ein- 

 stein equations exercise no physical discrimination, 

 and are consistent either with this mode of expression 

 or with the FitzGerald-Lorentz conception of the con- 

 traction of matter, which was a safer mode of express- 

 ing physical results than the attempt to impose com- 

 plications upon time and space. The paper gave rise 

 to some lively discussion from the supporters of the 

 more modern views. 



Mr. F. J. M. Stratton exhibited some spectrograms 

 of Nova Aquilae III. recently obtained at the Lick 

 Observatory by Mr. Moore, which show important 

 changes taking place in the distribution of radiation 

 from the growing disc of Nova Aquilae. It appears 

 that the disc given by the H|8 radiation is growing at 

 only half the rate of that given by the nebular lines 

 N,, N,, while the complex bands in the spectrum 

 corresponding with all three lines give the same 

 multiple of the wave-lengths for the displacement of 

 separate maxima. Moreover, the separate maxima 

 originate in different portions of the disc, and are 

 inclined to the normal position of spectral lines. A 

 complex combination of expansion, rotation, and 

 vortex motion is needed to explain the effects in terms 

 of the Doppler principle. While the maxima remain 



fixed in position, the most displaced ones are growing 

 brighter as compared with the central ones. 



A further paper on astrophysics was communicated 

 by the Rev. \. L. Cortie, who drew some remark- 

 able comparisons between observations on solar faculx 

 and photographs of calcium flocculi. The occurrence 

 of magnetic storms on the earth was attributed to 

 the emission of electrons from low, disturt>ed areas of 

 the sun, giving rise to the formation of clouds Into 

 which the earth then passed. 



The programme also included an interesting paper 

 by Prof. S. Chapman, who gave an account of some 

 recent extensions of his work on the subject of mag- 

 netic storms. Prof. Horton described the results 

 which he had obtained on ionisation phenomena in 

 neon ; and Prof. Whiddington showed how he had 

 been able to detect distances of molecular magnhude 

 by observing the variations of frequency in a 

 thermionic-valve circuit produced by the minute 

 changes of capacity resulting from the displacement 

 of one plate of a condenser included in the circuit. 



The reports of the Committees on Tidal Observa- 

 tions and on Seismology were of more than usual 

 interest; and in the latter report Mr. J. J. .Shaw 

 referred to his recent observations on microseisms. 

 Both communications are being published in the 

 reports of the Association. Much interest was added 

 to the proceedings of the Section by the opportune 

 appearance of the new star in Cvgnus. The discovery 

 was announced by the .Astronomer Roval at the first 

 session of the Section, and reports of later observa- 

 tions on the new star were received during the 

 meeting. 



Chemistry at the British Association. 



THE meetings of Section B at Cardiff were fairly 

 well attended, although the programme did not 

 contain any remarkable novelties, and the war papers, 

 which were so conspicuous a feature of the meeting 

 at Bournemouth, were absent. Mr. Heycock's presi- 

 dential address dealt with the development of metallo- 

 graphy, a branch of physical chemistry which owes 

 so much to the work of Heycock and Neville, whose 

 investigations not only opened up important new lines 

 of research, but also set a standard of accuracy which 

 has had a most beneficial effect on later work in 

 metallography, especially in this country. The lesson of 

 the intimate connection between pure science and the 

 advance of industry was well enforced by the address. 

 The president was able to show lantern-slides made 

 from the original photographs of Sorby taken just 

 half a century ago, and members were enabled to 

 appreciate the remarkable skill of the Sheffield 

 amateur who was a pioneer in so many branches of 

 science. 



The Section held only one joint meeting for the 

 purpose of hearing the papers in Section A on the 

 subject of isotopic elements. There was a very large 

 attendance at this meeting, and the latest discoveries 

 concerning the isotopes of the commoner elements 

 were described with admirable clearness by Dr. Aston. 

 It is to be regretted that no chemist took part in the 

 discussion. The doctrine of isotopes was founded on 

 chemical evidence, and although recent developments 

 have come chiefly from the physical side, the subject is 

 one of intense chemical interest, and the conclusions 

 which have been reached, inevitable as they appear 

 to be, call for a drastic revision of conventional ideas 

 regarding the elements. No chemist specially asso- 

 ciated with the work of determining atomic weights 

 was present, or it would have been interesting to learn 

 whether accurate atomic-weight determinations have 

 NO. 2663, VOL. 106] 



ever been made for a single element, other than those 

 of the radio-active group, from materials of widelv 

 different origin and geological age ; whether, for 

 example, such differences as have been observed 

 between specimens of lead from minerals containing 

 thorium and uranium respectively could be found 

 between chlorides of widely differing origin so as to 

 indicate that the isotopes of chlorine were present in a 

 different ratio from that which has led to the accepted 

 atomic weight of that element. The later paper of 

 Sir E. Rutherford on the structure of the atom was 

 also of great chemical importance, and considerations 

 of this kind have, in the hands of Langmuir and 

 others, been brought into direct relation with chemical 

 facts. It is to be hoped that by the time of the next 

 meeting of the -Association chemists will be prepared 

 to join with physicists in the discussion of these 

 questions. 



The three subjects selected for discussion on the 

 technical side were fuel, lubrication, and non-ferrous 

 metallurgy. Capt. Desborough's paper on industrial 

 alcohol gave an excellent review of the prospects of 

 production of this fuel from vegetable sources in tem- 

 perate regions, and showed that, whilst the present 

 cost of root crops grown on cultivated land is too high 

 to allow of their profitable utilisation as sources of 

 alcohol, the possibility of growing suitable crops on 

 reclaimed land is by no means excluded, and figures 

 were given to show that artichokes, sugar-beet, and 

 a South American tuberous plant are all deserving 

 of consideration. The use of maize in certain climates 

 and of waste cellulose is also being studied. The 

 experiments now in progress at the Royal Naval 

 Cordite Factory may be expected to throw some light 

 on the question, and the Section took occasion to pass 

 a resolution urging on the Government Departments 

 concerned the desirability of continuing such experi- 



