February 3, 192 1] 



NATURE 



735 



ruption until his death, where, for fourteen years, 

 he had been professor of physics and director of 

 the Sloane Physical Laboratory. Prof. Bumstead 

 was the most enthusiastic and devoted of Yale 

 men. He came over to Cambridge in 1904, and 

 worked for a year at the Cavendish Laboratory ; 

 the result of his work is contained in a paper in 

 the I'hilosophicul Magaoinc for June, 1906, p. 292, 

 on the heating effects produced by Rontgen rays 

 in different metals. On his return to America he 

 made, in spite of serious ill-health, important re- 

 searches on the properties of a-rays. 



Excellent as Prof. Bumstead 's published work 

 is, it gives but an inadequate idea of his powers, 

 or of his singularly clear and sane judgment. He 

 edited the collected works of VVillard Gibbs — the 

 greatest physicist ever associated with Vale. 

 When America joined in the war, he threw all his 

 energies into the application of science to the 

 purpo.ses of the war, and at the end of 191 7 he 

 <ame over to this country as Scientific Attache 

 to the American Embassy. Prof. Bumstead 's 

 duties were to co-ordinate the scientific work 

 done in .America and in England and France, so 

 that the results obtained in one country should 

 be as .soon as possible at the services of the 

 ithers. For this work his personal qualities and 

 M icntific attainments made him especially fitted, 

 and he did most valuable work whilst he was in 

 this country. He was at the time of his death 

 |)resident of the National Research Council in the 

 I'nited States. 



Prof. Bumstead had a singularly attractive and 



harming personality. Sympathetic, modest, 



without a trace of self-a.ssertion, he was the 



iiitist delightful companion and most valued 



riend. J. J. T. 



Pkinck I'. A. Kropotkin. 



Iiii, death of Prince P. A. Kropotkin at 

 Dmitrov, near Moscow, on F-'riday last, January 28, 

 deprives the world of a picturesque figure 

 and science of a devoted student. For many 

 >ears Prince Kropotkin was an esteemed 

 i-ontributor to the columns of Natuke, and 

 when he left England to return to Russia 

 in 1917 he wrote to express regret that 

 the very close relationships which had existed 

 between him and us for so long were being 

 severed. He said at the same time that he had 

 been a reader of .N'atikk from the first number, 

 and had even Ix-en permitted to receive it while 

 a prisoner in the fortress uf St. Peter .-ind St. I'.-iul 

 in St. Petersburg. 



Prince Kropotkin was lM)rn on liecember 9, 

 1H42. .At the age of fifteen he entered the select 

 n.ilitary school at St. I'etersburg ; on leaving he 

 joined a Cossack regiment stationed on the Amur, 

 :ind while aide-de-camp to the commander of the 

 (ieneral .Staff in F-'astern SiF)eria, he crossed North 

 .Manchuria from Transbaikalia to the .\mur and 

 up the Sungari to Kirin, travelling in all as many 

 a?) 50,000 miles. Fn 1H67 he abandoned a mili- 

 t.-trv career, and returned to St. Peters- 

 vo. 2675, vol. 106] 



burg, where he entered the University, and 

 devoted himself seriously to geographical work. 

 He then became closely associated with political 

 movements, and gave himself up to propaganda. 

 In 1873 he was arrested and imprisoned, but 

 escaped in the following year and made his 

 way to England, shortly afterwards going to 

 Switzerland. .\fter the assassiliation of .Alex- 

 ander 11., Kropotkin was expelled from Switzer- 

 land, and settled in Savoy, where he was arrested 

 in 1883 on a charge of organising a dynamite 

 outrage, and was condemned to five years' im- 

 prisonment, but was released in 1886. He then 

 returned to England, and remained here until 

 June, 1917. 



In 1876 Kropotkin published his "Researches 

 on the Glacial I'eriod," in which he described a 

 journey in I*'inland and a short visit to Sweden, 

 Ixjth made in 1871, under the auspices of the 

 Russian CJeographical Society, for the special pur- 

 pose of studying the glacial formations and the 

 eskers. His conclusions were that this low table- 

 land was once covered by an immense ice-sheet, 

 which, creeping from Scandinavia, crossed the 

 Gulf of Bothnia and traversed southern I''inland 

 in a direction south by east, leaving behind it the 

 marks of its course in the shape of numberless 

 stride and moraines. 



Perhaps Kropotkin's most notable work was 

 "Mutual .Aid, a I-'actor in Involution," published 

 in 1902. The view put forward was that in the 

 case of animals there is very little evidence of 

 any struggle for existence among members of 

 the same species, though plants, beyond all doubt, 

 jostle their own kin out of existence. Animals, 

 as a rule, are banded together for mutual pro- 

 tection, and those that have the best organisation 

 for mutual defence are those that thrive best. 

 .Among men, mutual aid is more general than 

 among animals ; among savages, it is the chief 

 factor in evolution. Kropotkin traced the growth 

 of the modern benefit societies, co-operative asso- 

 ciations, and trade unions back through succes- 

 sive stages of the history of a nation- through 

 the Stale, the medieval city with its fortifications 

 and hired defenders, the village communities, and 

 finallv to the clan, showing how man has attained 

 his present position chietly by practising mutual 

 aid. There is no doubt that in the development 

 of this thesis Kropotkin was keenly interested, 

 and that the work itself represents, more closely 

 than anything else he did, the main trend of his 

 conception of the meaning of life and progress. 



Kropotkin was a pioneer advocate of the in- 

 tensive cultivation of crops, and in a suggestive 

 little hook entitled " I'ields. l-actories, and Work- 

 shops " he described what was done in this direc- 

 tion in Guernsey, as well as indicale<l how similar 

 principles of culture could be applied elsewhere. 

 FFis view was "that fxx) persons could easily live 

 nn a square mile, and that with cultural methods 

 already used on a large .scale 1000 human beings 



not idlers - living on 1000 acres <-ould easily, 

 without any kind of overwork, obtain from that 

 area a luxurintis x-egetable and animal fofnl, a* 



