NOTES 635 



X-rays originated at the platinum target. Only a fortnight 

 later, on March 3, C. T. R. Wilson described to the Royal 

 Society the effect of the rays in providing nuclei on which 

 water vapour could condense when it was subject to sudden 

 expansion. The later researches on the properties of the 

 rays, which may be said to have culminated (on the physical 

 side at least) with their application to crystal structure, will 

 be familiar to readers of Science Progress. It may, how- 

 ever, be interesting to note that the method of reflection at 

 grazing incidence which finally settled their nature was tried 

 by Fitzgerald and Trouton in Dublin as early as 1896, but 

 these investigators used lead and paraffin wax as reflecting 

 surfaces. Rontgen himself, in his original paper, had de- 

 scribed experiments which may be regarded as the prototype 

 of those performed by Laue, to see whether the geometrical 

 arrangement of the molecules in Iceland spar and quartz had 

 any effect on the rays, but without obtaining any positive 

 result. 



The Nobel Chemistry Prizes for 1921 and 1922 



Dr. F. W. Aston. 



Dr. F. W. Aston, who was awarded the prize for 1922, was born on 

 September i, 1877, at Harborne, Birmingham. He was educated at Malvern 

 College, and the Universities of Birmingham and Cambridge. After a year 

 spent as assistant Lecturer in Physics at Birmingham he entered the 

 Cavendish Laboratory in 1910, obtained his B.A. by research in 1912, and 

 was appointed to the Clerk Maxwell studentship in 191 3. During the war 

 he held an appointment on the technical staff of the R.A.F. at Farnborough. 

 Returning to his researches at Cambridge in 19 19, he rapidly attained suc- 

 cess with a new method of positive-ray analysis. In 1920 he was elected to 

 a Fellowship at Trinity College and received the Mackenzie-Davidson medal 

 of the Rontgen Society ; in 192 1 he was elected Fellow of the Royal Society. 

 His work first came into prominence at the B.A. meeting in 1913 owing 

 to the communication of a preliminary account of his attempts to separate 

 from the element neon (atomic weight 20-2) a second element of atomic weight 

 22, whose existence was indicated by Sir J. J. Thomson's experiments with 

 positive rays. Prolonged fractionation of the two gases by absorbing them 

 in charcoal cooled by liquid air (whereby the absorption of the heavier 

 constituent was expected to be greater than that of the lighter) having 

 failed, Aston had designed an automatic apparatus in which the two gases 

 were continually diffusing through a pipeclay tube, and announced that he 

 had succeeded in dividing the original gas into two parts of which one had a 

 slightly greater density than the other. This was considered at that time 

 as being the first separation of a non-radio-active element into its isotopes, 

 and the element of atomic weight 22 was called metaneon. The diffusion 

 experiments were continued until they were interrupted by the war, at 

 which time no really decisive evidence for any such separation had been 

 obtained. 



After the war, however, Aston placed our knowledge of the isotopic 

 character of the elements on a firm basis by means of the apparatus known 

 as the mass-spectrograph which he himself described in Science Progrjess 



