1^2 



NATURE 



[March 21, iqii 



elastic liquids and solids. The " spherical shadow " con- 

 ception which I hnv«' employed in connection with trans- 

 verse waves applies equally well here. 



So far as I am aware, longitudinal waves in the ather 

 are unknown, but that such waves have not been observed 

 is not convincing argument that they do not exist. 



Assuming, then, that some, or perhaps much, of the 

 intrinsic energy of the a-ther is embodied in longitudinal 

 waves, we have only to fuid some motive action of such 

 waves on atoms of matter to account for gravitation. 

 Adequate motive connection may perhaps \k effected by 

 the locally alternating flow and ebb— acceleration and 

 retardation of the a-ther in which the atoms are enmeshed, 

 incident to its wave motion. We have ample reason for 

 believing that the a.ther does obtain a grip of some sort 

 on the atoms of an accelerating (falling) body and a retard- 

 ing (rising) body, from which it follows that accelerating 

 and retarding .x'ther, as in a wave of compression, must 

 grip a comparatively stationary atom. 



Certain facts of astronomy apparently require that 

 gravitational attraction between bodies, however distant 

 from each other, must, in effect, be instantaneous ; that 

 is to say, the line of apparent attraction between them is 

 a straight line joining their centres. I believe my theory 

 meets this condition, but shall reserve discussion of the 

 point for a future paper. 



I feel much diffidence in presenting the foregoing rough 

 draft of a theory of gravitation, but I cannot avoid the 

 belief that it contains some germs of truth, perhaps the 

 real key to the great mystery, though, if this be true, I 

 have no doubt used the key clumsily and imperfectly. 



If the aether-wave theory of gravitation is, in the main, 

 the true one, it offers some hope of experimental verifica- 

 tion. Provided the waves are of one principal frequency, 

 or even of several, we may find something, doubtless of 

 molecular magnitude only, which will oscillate in unison 

 with them so that resonance can occasionally be estab- 

 lished and a cumulative effect be obtained sufficient to 

 manifest itself as heat. 



In searching for some natural phenomenon of this 

 nature, I thought of the thermal condition of the upper 

 atmc«phere as a possible case. The mean molecular 

 velocity of a gas at some temperature, in connection with 

 the mean free path of its molecules at some particular 

 pressure or pressures, may possibly afford the necessary 

 conditions for fortuitous resonance, with development of 

 some slight amount of heat by the increased violence of 

 inter-molecular collisions. I have done much experimental 

 work on these lines during the past year, but, notwith- 

 standing refinement of method and ' manipulation, the 

 results have thus far been unsatisfactory. The work is 

 still in progress, however, and investigation of other 

 phenomena is contemplated. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 



Cambridge.— Mr. R. C. B. Gardner has been appointed 

 assistant to the superintendent of the Museum of Zoology, 

 and the appointment has received the consent of the Vice- 

 Chancellor. 



The special board for biology and geology has nominated 

 Mr. J. F. Gaskell to use the University table at Naples 

 for three months, and Mr. W. O. R. King to occupy the 

 University table at the laboratory of the Marine Biological 

 Association at Plymouth. 



On Thursday, April 27, a Grace will be brought before 

 the Senate suggesting that the laboratory of experimental 

 psychology syndicate be authorised to obtain tenders for 

 the erection of a building for the psychological laboratory 

 in accordance with Mr. Jackson's plans, and that the 

 Vice-Chancellor be authorised to sign the contract for the 

 work provided that the total cost does not exceed 4250?. 



It is announced in the Revue scientifiqtie that Mr. 

 Arthur Krupp has given 50,000 crowns to the Vienna 

 School of Arts and Crafts towards the establishment of an 

 aviation laboratory. 



In connection with the celebration of the centenarv of 



the Lniversity of Breslau, Dr. P. Schottlaender has given 



NO. 2160, VOL. 86] 



the Unlver«iiy ^50,000 mark*, the interest of wlii..n. 

 the lievue scienlifique, is to be devoted to the provisi< 

 travelling exhibition* or to the purposes of research. 



At a meeting of the Ix)ndon branch of the Association: 



of Teachers in Technical Institutions, to be held «>" ^ 



dav, March 25, at the South-Western Polytechnii . 

 S.VV'., a conference on the organisation of tech 

 struction, especially in connection with the li , 

 branches, will be opened by Dr. R. T. Glazebi 

 r.R.S., director of the National Physical Laboratory. 



The London Inter-collegiate Scholarships Board 

 announces that an examination will be held on M.: 

 for eighteen entrance scholarships and e.\hibitions, < 



aggregate total value of about 1500/., op*n • 



women, and tenable in the faculties of art- 

 engineering of University College, King's t <■ „ , 

 East IvOndon College. Particulars and entry forms may 

 be obtained from the secretary of the Hoard, Mr. A. E. O. 

 Attoe, University College, Gower Street, W.C. 



Mr. Alexander Siemens, president of the Institutio 

 Civil Engineers, speaking at the annual dinner of 

 institution on March 17, said that the institution pro;, 

 to inaugurate a conference on engineering education di 

 the summer with the object of making clear the p: 

 way of preparing young men for the profession of engi; 

 ing. The passing of examinations is part of wh.i 

 needed, he pointed out, but not all. The great thiiu 

 practical training, so that young men may know how to 

 employ their theoretical knowledge and be prepared to 

 take up any branch of engineering which fate may <^ ' 

 them to. Mr. Siemens hopes that the institution will 

 an opportunity at the forthcoming Imperial Confereni 

 represent to the Colonies the desirability of recognising 

 qualifications of its members and of according 

 uniform treatment throughout the Empire. 



The Home Secretary has appointed a committe* 

 inquire into the constitution, management, discipline, and 

 education of reformatory and industrial schools in England 

 and Wales. The inquiry will include a consideration of 

 the relation of the schools to education committees and 

 other authorities, and the qualifications of superintend'"*- 

 and other officers ; variation in the types of schools, 

 whether further provision is necessary for the pr _ 

 grading of boys and girls ; the suitability of ships for use 

 as schools ; the preparation given boys for entry into 

 industrial or other careers, and the training and disposal 

 of girls ; the care of boys and girls after leaving the 

 schools and the relation of the schools in this connection 

 to existing institutions for the welfare of young persons. 

 The committee appointed is representative in character. 1: I 

 Mr. C. F. G. Masterman, M.P., is the chairman. 

 A. Maxwell, of the Home Office, will act as secretary. 



The Board of Education has found it impossible to com- 

 plete the preparation of the new grant regulations for 

 technical schools, schools of art, and other forms of pro- 

 vision of further education in England and Wales, at a« 

 early a date as was suggested in the prefatory men 

 andum to the regulations issued last .August. This ! 

 so, the Board feels that to bring new regulations into fv., >• 

 by -August I next would allow insufficient time to educa- 

 tion authorities for accommodating their arrangements to 

 the requirements of the new regulations. The grant r 

 lations for iqio are, therefore, to be continued in f 

 during the educational year iqn-12, and the Board li 

 in the course of the coming summer to issue the 

 regulations, which will not, however, become operiiin- 

 until the educational year 1012-13. The new regulations 

 may thus be in the hands of education authorities a year 

 before they come into force. The Board announces, how- 

 ever, that it will not be necessary similarly to defer the 

 issue or the operation of the new regulations for university 

 institutions. The Board contemplates issuing separate pro- 

 visions in resp>ect of the educational year 1911-12 for the 

 payment of grant in aid of approved courses provided by 

 university institutions. .Any courses so aided will cease to 

 be eligible for recognition under the Board's regulations for 

 technical schools. New regulations for the science and art 

 examinations, the National competition, and the various 

 forms of scholarships and exhibitions given and aid<«l by 

 the Board are under consideration, and it is hoped that 



