Dfcember I, 1904] NATURE 



109 



of the phenomena of nature by direct observation and ex- 

 periment, an integral and essential part of all education in 

 this country. 



I proceed to the award of the medals. 



Copley Medal. 



The Copley Medal is awarded to Sir William Crookes, 

 F.R.S., for his experimental researches in chemistry and 

 physics, extending- over more than fifty years. Ever since 

 his discovery of the element thallium in the early days of 

 spectrum analysis, he has been in the front rank as regards 

 the refined application of that weapon of research in 

 chemical investigatirm. Later, the discrepancies which he 

 found in an attempt to improve weighings, by conducting 

 the operation in high vacua, were tracked out by him to a 

 repulsion arising from radiation, which was ultimately 

 ascribed by theory to the action of the residual gas. This 

 phenomenon, illustrated by the radiometer, opened up a new 

 and fascinating chapter in the dynamical theory of rarefied 

 gases, which the genius of .Maxwell, O. Reynolds, and 

 others, has left still incomplete. The improvements in 

 vacua embodied in the Crookes tube led him to a detailed 

 and brilliant experimental analysis of the phenomena of the 

 electric discharge across exhausted spaces ; in this, backed 

 by the authority of Stokes, he adduced long ago powerful 

 cumulative evidence that the now familiar kathode rays, 

 previously described by C. F. Varley, must consist of pro- 

 jected streams of some kind of material substance. His 

 simple but minutely careful experiments on the progress of 

 the ultimate falling off in the viscosity of rarefied gases, 

 from the predicted constant value of Maxwell, at very high 

 exhaustions, gave, in Stokes's hands, an exact account of 

 the trend of this theoretically interesting phenomenon, which 

 had already been approached in the investigations of Kundt 

 and Warburg, using Ma.xweU's original method of vibrating 

 discs. 



These examples, not to mention recent work with radium, 

 convey an idea of the acute observation, experimental skill, 

 and persistent effort, which have enabled Sir William 

 Crookes to enrich physical science in many departments. 



Eumford Medal. 



The Rumford Medal is awarded to Prof. Ernest Ruther- 

 ford, F.R.S., on account of his researches on the properties 

 of radio-active matter, in particular for his capital discovery 

 of the active gaseous emanations emitted by such matter, 

 and his detailed investigation of their transformations. The 

 idea of radiations producing ionisation, of the type originally 

 discovered by Rontgen, and the idea of electrified particles, 

 like the kathode rays of vacuum tubes, projected from radio- 

 active bodies, had gradually become familiar through the 

 work of a succession of recent investigators, when Ruther- 

 ford's announcement of a very active substance, diffusing 

 like a gas with a definite atomic mass, emitted by compound 

 of thorium, opened up yet another avenue of research with 

 reference to these remarkable bodies. The precise interpre- 

 tation of the new phenomena, so promptly perceived by 

 Rutherford, was quickly verified, for radium and other sub- 

 stances, by various observers, and is now universally ac- 

 cepted. The modes of degradation, and the enormous con- 

 comitant radio-activity, of these emanations, have been in- 

 vestigated mainly by Rutherford himself, with results 

 embodied in his treatise on radio-activity and his recent 

 Bakerian lecture on the same subject. It perhaps still 

 remains a task for the future to verify or revise the details 

 of these remarkable transformations of material substances, 

 resulting apparently in the appearance of chemical elements 

 not before present ; but, however that may issue, by the de- 

 tection and description of radio-active emanations and their 

 transformations. Prof. Rutherford has added an unexpected 

 domain of transcendent theoretical interest to physical 

 science. 



Royal Medal. 



A Royal Medal is awarded to Prof. W. Burnside, F.R.S., 

 on the ground of the number, originality, and importance of 

 his contributions to mathematical science. The section of 

 our " Catalogue of .Scientific Papers " for the period 1883- 

 1900 enumerates fifty-three papers by Prof. Burnside, the 

 first dated 1885, and the " International Catalogue of Scien- 

 tific Literature " thirteen more. His mathematical work 



has consisted largely of papers on the theory of groups, to 

 which he has made most valuable additions. In 1897 he 

 published a volume " On the Theory of Groups of Finite 

 Order," which is a standard authority on that subject. Two 

 recent papers on the same theory, published in 1903, may be 

 specially mentioned. In one of these he succeeded in estab- 

 lishing by direct methods, distinguished by great conciseness 

 of treatment, the important subsidiary theory of group- 

 characteristics, which had been originally arrived at by 

 very indirect and lengthy processes. In the other he proved 

 quite shortly the important result that all groups of which 

 the order is the product of powers of two primes are soluble. 

 Besides the t.reatise and papers relating to group theory, 

 Prof. Burnside has published work on various branches of 

 pure and applied mathematics. His work on automorphic 

 functions dealt with an important and difficult special case 

 which was not included in the theory of these functions as 

 previously worked out. The paper on Green's function for 

 a system of non-intersecting spheres was perhaps the first 

 work by any writer in which the notions of automorphic 

 functions and of the theory of groups were applied to a 

 physical problem. He has also made important contribu- 

 tions to the theory of functions, non-Euclidean geometry, 

 and the theory of waves on liquids. His work is distin- 

 guished by great acuteness and power, as well as by unusual 

 elegance and most admirable brevity. 



Royal Medal. 



The other Royal Medal is awarded to Colonel David 

 Bruce, F.R.S., who, since 1884, has been engaged _ in 

 prosecuting to a successful issue researches into the causation 

 of a number of important diseases affecting man and 

 animals. When he went to Malta in 18S4 the exact nature 

 of the widely prevalent " Malta," " Rock," or " Mediter- 

 ranean " fever was entirely unknown. .After some years' 

 work at the etiology of this disease, he discovered in 1887 

 the organism causing it, and succeeded in cultivating the 

 Micrococcus melitensis outside the body. This discovery 

 has been confirmed by many other workers, and is one of 

 great importance from all points of view, and perhaps more 

 especially as, thanks to it, Malta fever can now be separated 

 from other diseases, e.g. typhoid, remittent, and malarious 

 fevers, with which it had hitherto been crnfounded. 



During the next few years he was engaged in researches 

 of value on cholera, and on methods of immunisation against 

 this disease. He also carried out some work on the leuco- 

 cvtes in the blood, published in the Proceedings of the Royal 

 .Society, 1894. 



In 1894 he was requested by the Governor of Natal to 

 investigate the supposed distinct diseases of " nagana " 

 and the tsetse-fly disease. In the short time of two months 

 he made the most important discovery that these two dis- 

 eases were one and the same, and dependent upon the 

 presence of a protozoan organism in the blood, known as a 

 trypanosome. Some six months later Bruce was enabled to 

 return to Zululand, and remained there two years, studying 

 the disease and making the discovery that the tsetse fly 

 acted as the carrier of the organism which caused it. He 

 was thus the first to show that an insect might carry a 

 protozoan parasite that was pathogenic. This observation 

 was made in 1895. 



Bruce not only determined the nature and course of 

 " nagana," but in addition he studied the disease in a large 

 number of domestic animals, and also observed the malady 

 in a latent form in the wild animals of South Africa. Sub- 

 sequent observers have found but little to add to Bruce's 

 work on this subject. 



In 1900 Bruce was ordered to join a commission investi- 

 gating the outbreak of dysentery in the .Army in South 

 Africa, and a great part of the laboratory work performed 

 by this commission was carried out by him. 



' In 1903 Colonel Bruce went, at the request of the Royal 

 Society, to Uganda, to investigate further the nature of 

 sleeping sickness. It was very largely, if not entirely, 

 owing to him that the w-ork of the Royal Society's com- 

 mission was brought to a successful issue. At the time 

 when he arrived a trypanosome had been observed by 

 Castellani in a small number of cases of this disease ; thanks 

 to Bruce's energv and scientific insight, these observations 

 were rapidlv extended, and the most conclusive evidence 

 obtained, that in all cases of the disease the trypanosome 



NO. I 83 I, VOL 71] 



