July 13, 191 1] 



NATURE 



5i 



support in Preston's observations on the Zeeman 

 ellect. 



He took a keen interest in the development of the 

 kinetic theory of gases, to which he made notable 

 contributions. In 1807 he arrived at his estimate of 

 the size of molecular dimensions, which is substantially 

 that made by Kelvin a year or so later, and by 

 Loschmidt two years previously. 



By utilising- his value of the mass of the atom 

 Stoney was able to give, at the Belfast meeting of 

 the British Association in 1S74, the first calculation 

 of the atomic charge in electrolysis. To this quantity 

 he gave the name electron, which is now very gener- 

 ally adopted, and has proved a most suitable term. 

 It uas to the orbital movements of the electrons 

 in the atoms, to which, as we have seen, Stoney 

 attributed in 1891 the spectral lines and their various 

 singularities. 



Stoney invariably invented a nomenclature for the 

 quantities he was dealing with, where none already 

 existed. Such new terms are continually to be met 

 with in his writings. Many of them have been found 

 by others to be most convenient, and have conse- 

 quentlv taken root in science, as, for example, his 

 term wavelet, employed advantageously in his 

 papers on microscopic vision, in connection with his 

 method of resolution into plane wave fronts. This 

 facility in suggesting suitable terms proved most 

 useful when serving on the now famous committee 

 of the British Association which devised our present 

 system of electrical units, and of which he was one 

 of the early members. 



Stoney was the first to see that the movements in 

 Crooke's radiometer were not due to radiation directly, 

 but arose from unsymmetrical gaseous impacts result- 

 ing from unequal heating of the surfaces of the 

 rotating vanes. His original explanation, however, 

 required modification, afterwards supplied by Max- 

 well and Osborne Reynolds. 



He introduced into cosmical physics considerations 

 of a limit to each planet's power of retaining a 

 gaseous envelope, which are of the highest interest in 

 connection with the moon and with Martian questions. 

 He showed that helium, as well as hydrogen, must 

 ev»ntuallv escape from the earth's atmosphere, a fact 

 with important bearings on the past history of the 

 radio-activity of the materials of the earth's crust. 



Stoney 's ideas were sometimes rather ahead of the 

 recognised requirements of the day, and consequently 

 paid the penalty of neglect which unfortunately some- 

 times happens in such cases ; indeed, one of his papers 

 on a periodic scheme of the elements, predicting, 

 among other points, the atomic weights of the "inert " 

 group, remained unpublished on the mistaken advice 

 of one of the greatest of his contemporaries. This 

 verv scheme is now thought by many to be the most 

 satisfactory of any yet devised. 



He was essentially of a philosophic turn of mind, 

 and wrote several papers on ontology and kindred 

 subjects, but at the same time he took delight in all 

 new developments of both industry and science, re- 

 joicing that his span of life had coincided with what 

 he considered would probably prove in the world's 

 history to have been the period of most rapid advance, 

 flowing from the first systematic application of scien- 

 tific method on an extended scale to industrial pro- 

 gress. He would describe how as a child he had wit- 

 nessed the first use of illuminating gas in the streets 

 of Paris, and would with evident pleasure recount 

 the many achievements of man in his time. 



Stoney was born in King's Co., Ireland, in 1826. 



His mother was -a Blood of County Clare. His 



ancestry belongs to the Protestant settlers in Ireland 



of the sixteenth and seventeenth centuries, a class 



NO. 2176, VOL. 87] 



from which has sprung so many of our great men ot 

 science, including Hamilton, Stokes, and Kelvin, but 

 which, through economic and political causes, is now- 

 fast disappearing. He came from strong stocks on 

 both sides, which have provided an unusually large 

 number who have made their mark, including four 

 Fellows of the Royal Society. 



He was educated at Trinity College, Dublin, taking 

 high place in his examinations. He was anxious to 

 devote his life to collegiate work, and sat for the 

 fellowship examination, the entrance in Trinity College 

 to this, but, as in many other cases, his brilliant 

 intellect was lost to his university through the un- 

 fortunate working of an examination system, now 

 happily to be abolished. 



For many years he held the post of secretary to 

 the Queen's University of Ireland, a position afford- 

 ing- him small leisure for pursuing his scientific re- 

 searches. To his official duties he gave a whole- 

 hearted service. This involved much organisation of 

 the scattered colleges which constituted that university, 

 and it was with unfeigned regret he saw the work 

 of these years abandoned on its dissolution. 



All who came in contact with Johnstone Stoney were 

 impressed with his sincerity and devotion to all which 

 makes for truth and righteousness. He was veritably 

 a prophet as of olden time. Younger scientific men 

 who have had the privilege of knowing him will not 

 easily forget his kindliness and encouragement. 



He died on Julv t, after a prolonged illness, in his 

 eighty-sixth year, at his residence at Notting Hill 

 Gate, where he had lived for some years. 



F. T. T. 



NOTES. 



A new attempt is being made to work the alluvial gold- 

 field in Helmsdale, in pastern Sutherland. The existence 

 of gold there has long been known, and some of the gold 

 of the ancient ornaments found in north-eastern Scotland 

 may have come from that district. The first modern 

 attempt to work the field was in 1869. when gold was 

 obtained in the Kildonan and Suisgill Burns, two tribu- 

 taries of the Ullie, the main stream of Helmsdale. 

 Royalty was paid on about 3000L of gold, but the amount 

 obtained is said to have been considerably higher. The 

 largest nugget was found in the Kildonan Burr., and 

 weighed two ounces. The richest alluvial deposits were 

 in the Suisgill Burn, a higher tributary of the Ullie. This 

 burn flows over mica schists belonging to the Moine 

 system, which have been invaded by granite dykes. The 

 existence of gold in this granite w-as recorded by Bryce 

 in 1870. The workings were stopped at the end of 1869 

 owing to damage done to the fishing and the farmers. A 

 serious effort to reopen the field is now being made by 

 the Duke of Sutherland. Gold is being obtained, but 

 whether it occurs in paying quantities has still to be 

 proved. 



Dr. H. N. Dickson, president of the Royal Meteor- 

 ological Society, in a letter to The Times of Thursda) , 

 July 6, raises the question of increasing the utility of the 

 daily forecasts of weather issued by the Meteorological 

 Office by more effective distribution. His letter suggests 

 the general restoration of the afternoon service of weather 

 forecasts, which is now only operative in the summer 

 months. " Presumably these could be issued all the year 

 round, and they could easily reach the general public before 

 the arrangements for the next day's work were finally 

 completed, provided proper facilities for distribution were 

 given." The history of the public announcement of 

 weather forecasts in this country includes some interesting 



