October 26, 1905J 



NA TURE 



643 



ance, the galvanometer points to its presence hindering 

 the dissolution of the gold ; the cause of the disagreement 

 between the instruments he attributes to the formation of 

 local voltaic circuits. Mr. H. A. White gave an account 

 of a series of experiments which showed that thiocyanates 

 in presence of such oxidising agents as ferric salts attack 

 gold with considerable ease, and that thiosulphates exert 

 a similar but less powerful influence. These salts are 

 present in ordinary working cyanide solutions, and the 

 presence of gold in mine reservoirs and in the soil under 

 residue dumps is probably connected with their occurrence. 

 Experiments adduced by the author indicate that in well 

 exposed dumps thiocyanates alone are of significance in 

 respect to the observed solution of gold. .A process of 

 residue treatment, based on these facts, is resulting in the 

 profitable extraction of a large proportion of the gold in 

 certain of the residue dumps on the Rand. 



At the second day's meeting, Dr. J. Moir discussed the 

 law governing the solubility of zinc hydroxide in alkalis, 

 and as the result of a quantitative research stated the 

 conclusion that the phenomenon is essentially an equil- 

 ibrium between alkali and zincic acid, which may be 

 reached from both sides, and which depends solely on the 

 concentration of the free alkali. It was also shown that 

 no definite chemical compounds exist in the solution. Mr. 

 G. W. Williams read a paper on the functions of the 

 metallurgical laboratory, dealing with the uses of the 

 laboratory for the testing of supplies and for purposes of 

 research, and with the personnel and equipment of a suit- 

 able laboratory. He emphasised the necessity for a highly 

 trained staff, and pointed out defects in the training given 

 in the great English universities. In a valuable contribu- 

 tion, Mr. S. H. Pearce stated and discussed various 

 economic problems in metallurgy on the Rand. Each stage 

 of the whole process of gold extraction was considered from 

 the economic as well as from the scientific standpoint, and 

 the results of the practical experience of years were sum- 

 marised in a very clear and judicial manner. Much 

 technical information, of value to all interested in gold 

 extraction, was given in this paper. Mr. R. L. Cousens 

 gave an account of the experiments which led him to 

 conclude that a radio-active substance is present in a 

 certain ore discovered in the Transvaal. If a further 

 examination of the material confirms his belief that the 

 radio-activity of the ore is due to the presence of radium, 

 the result will be of interest in view of the fact that 

 uranium is not present in the ore. 



The third day of the meeting was devoted to agricultural 

 chemistry. The proceedings were opened by Mr. A. D. 

 Hall, who discussed in greater detail some of the problems 

 touched on in his address at Cape Town. In a paper on 

 Pretoria rain, Mr. H. Ingle stated that the rain falling 

 at Pretoria for twelve months from February, 1004, was 

 collected, and its content of nitrogen, existing as nitrates, 

 nitrites, and ammonia, determined each week. The results 

 showed that the quantity of combined nitrogen brought 

 down in the rain at Pretoria is considerably greater than 

 the average amounts in Europe, amounting in twelve 

 months to 7-07 lb. of nitrogen per acre as compared with 

 the average of 3-84 lb. per acre at Rothamsted. In a 

 second paper Mr. Ingle communicated the results of the 

 analyses of some eighty samples of soils collected in 

 various parts of the Transvaal, and drew a comparison 

 between European and Transvaal soils, with special refer- 

 ence to the interconnection of their chemical composition 

 and fertility as indicated bv field experience. He showed 

 that to take English standards in judging of fertility from 

 chemical analysis may lead to erroneous conclusions in the 

 case of tropical or subtropical soils, and that if there be a 

 sufficient supply of water a soil of apparently poor quality, 

 from analytical results, may yield luxurious crops under 

 the favouring conditions of growth existent in the Trans- 

 vaal. Mr." E. H. Croghan, in a paper on the fuel of the 

 midland districts of South Africa, pointed out that a large 

 proportion of potash is found in the excreta of sheep fed 

 in this dry and treeless region, resulting from the com- 

 position of the bushes, the foliage of which constitutes the 

 chief food of sheep and cattle. Owing to want of water 

 for irrigation the farmer does not use sheep excreta for 

 inanure, but for fuel, and the ashes frequentlv accumulate 

 near the homestead. Attention was directed to the 



NO. 1878, VOL. 72] 



economic value of these ash heaps, either as a manure or 

 as a source of potassium carbonate. Reports were pre- 

 sented by the committee on wave-length tables of the 

 spectra of the elements, the committee on the study of 

 hydro-aromatic substances, and the committtee on the 

 transformation of aromatic nitroamines. 



SCIENTIFIC RESEARCH IN MEDICINE} 

 'X'HAT great benefits to mankind have followed the dis- 

 coveries of recent years is obvious to all, especially 

 with regard to the causes and prevention of yellow fever 

 and malaria. Research is a word heard on all sides ; it 

 is the enemy of authority, that tyrannous spirit which has 

 hampered progress and retarded the advance of scientific 

 medicine for centuries. Experimental medicine is re- 

 sponsible for the greatest advances which have been made 

 in our knowledge of the cause, prevention, and cure of 

 disease. Most important discoveries have exerted but a 

 slight direct influence at, their inception ; their full signifi- 

 cance has remained hidden for a time. The majority of 

 such discoveries has been made by those engaged in re- 

 search in the realms of pure science. Pure science is 

 unselfish ; its aim is not profit, yet it is the forerunner of 

 that applied science which is more obtrusively the " servant 

 of man." If we study disease, we must do so for 

 the sake of knowledge, the scientific spirit must enter 

 into our work. The " practical man " may not appreciate 

 such ideals, but he is ever ready to use the discoveries 

 of science for his own ends. All are not born with the 

 instincts of research, but there are many in whom they 

 lie dormant, and it should be the function of educational 

 institutions to detect and foster such men and lead them on 

 to do the work for which they are adapted. But too often 

 from mere lack of means such men drift away into other 

 fields of activity. To carry on research successfully a man 

 needs an assured income. Is it possible that those who 

 are able and willing to help human progress can continue 

 to ignore the devotion and self-sacrifice of such men as 

 Lazear, Myers, Dutton, Plehn, and others who have laid 

 down their lives in the study of tropical medicine? 

 Medical research needs endowment, and it is grievous to 

 see that in this country, where so much is done for charity, 

 so pitiably little is done for the advancement of learning. 

 To teach science as it should be taught in properly 

 equipped and organised institutions is far more expensive 

 in the case of medicine than in that of any other pro- 

 fessional school. It does not suffice to build laboratories ; 

 they must also be provided with sufficient funds and equip- 

 ment to enable them to become working entities. 



Those who have watched the progress of the London 

 School of Tropical Medicine from its inception have wit- 

 nessed a struggle upward which is worthy of all praise. 

 This, and the sister institution in Liverpool, are known 

 throughout the world for the excellent work accomplished 

 by the members of the teaching staff and by some of the 

 students they have sent forth. The London School has a 

 great mission to fulfil ; it has to train men in the methods 

 they will be called on to employ in many parts of the 

 world, and to give them the latest and the best to take 

 with them on their distant journeys. It is to be hoped that 

 the public will second the noble efforts that have been 

 made to establish a centre for the study of the diseases 

 which affect the inhabitants of the tropical countries of 

 this vast Empire. 



The Trend of Recent Investigation. 

 A survey of recent work in tropical medicine shows us 

 that investigation is chiefly being directed to the study of 

 protozoal diseases. No advances of fundamental import- 

 ance have been made with regard to malaria since the 

 classical investigations were published with which the 

 names of Ross and Manson, Grassi, Bignami and Bastian- 

 elli will ever remain associated. The earlier work has 

 been confirmed and extended by many investigators. The 

 prevention of malaria by means of mosquito destruction 

 and other measures directed against mosquitoes has been 

 tried in various localities, in some instances with success, 

 1 From an address delivered at the opening of the nineteenth session of 

 the Lrndor School of Tropical Medicine on October 11, by Dr. Georse 

 Nutlall, F.R.S. 



