596 



NATURE 



[August 2"], 1908 



Subjoined are extracts from the address prepared 

 by Sir Walter Hely-Hutcliinson, president ot the 

 South Airican Association : — 



A remarkable advance has taken place in Soutli Africa 

 of late years in the matter of general public interest in 

 scientific matters. Scientific men have taken an interest 

 in, and have studied, South Africa for more than 150 

 years — La Caille, Le Vaillant, Herschel, Burchell, Lichten- 

 slein, Andrew Smith, for e.sample, are names which will 

 be familiar to you, and will always be remembered in con- 

 nection with early scientific inquiry and development in 

 South Africa. Hut it is not so many years ago that 

 scientific men were prone to be generally regarded in 

 South Africa as an interesting class of persons who un- 

 selfishly devoted their lives to asking questions of nature, 

 and to getting further conundrums for answers — amiable 

 enthusiasts wno actually wori-ced, many of them, for 

 nothing, read papers to each other on all sorts of abstruse 

 subjects at the meetings of the Philosophical Society, and 

 no doubt found out a great many interesting things, but 

 were more or less outside the real and practical business 

 of making a living. The general and commonplace view 

 probably was, that when it came to dealing with the 

 problems and difficulties of everyday life, your " practical 

 man " was more likely to be successful, or more useful 

 as an adviser, than the scientific man who was continually 

 betraying an almost indecent curiosity about the secrets of 

 nature, which, in some of its phases, might be regarded 

 by many people as not wholly orthodox or reverent, and de- 

 voted his time and his intellect to the solution of questions 

 which did not appear to have any practical bearing on the 

 ordinary problems of life. By degrees, however, the prac- 

 tical value of scientific inquiry, and of scientific knowledge, 

 became more generally apparent. Overlapping boundaries 

 of farms, for instance, and consequent litigation, demon- 

 strated the necessity of a scientific system of survey. 

 Thousands of pounds have since been spent on the 

 triangulation of the Cape Colony, and a secondary triangu- 

 lation is in progress. The main triangulation has been 

 extended throughout South Africa, and the work has been 

 carried forward through Northern Rhodesia to Tanganyika 

 in the shape of a geodetic survey which will in due course 

 be prolonged to Cairo. With this great work the name 

 of David Gill, the first president of this association, will 

 always be honourably associated. The American inquiry 

 into the causes of Texas fever, and the scientific demonstra- 

 tion of the fact that the disease was carried by ticks, led 

 to the scientific investigation of the causes of the many 

 other diseases which affect our flocks and herds in this 

 country ; and whereas twenty years ago there was no 

 bacteriological laboratory in South .Africa supported by 

 public funds, now there arc at least four. The most re- 

 markable advance has been made in the matter of discover- 

 ing the means of immunising domestic animals against 

 the manifold diseases to which they are subject in this 

 countrv, and the great progress which has been attained 

 in ascertaining the true causes of these diseases promises 

 to lead to the discovery, in time, of the means of immunisa- 

 tion against all of them. It is, indeed, in the matter of 

 fighting disease, whether amongst animals or plants, that 

 the practical application of the results of scientific study 

 has made its utility evident to the mass, especially to the 

 rural portion, of the population. The mining industry has 

 alwavs been a scientific industry ; its successful develop- 

 ment, whether on the mechanical or on the metallurgical 

 side, has always evidently depended on the advancement 

 of science in its own particular spheres ; but to impress on 

 a practically minded rural population the inestimable value 

 to themselves, and to their pastoral and agricultural under- 

 takings, of scientific research (costly and slow as it neces- 

 sarllv Is, and always must be) litis been a work of time, 

 and has required many object-lessons. 



Let me record some of the achievements of science, in 

 this one matter of immunisation against disease, in the 

 course of the last ten or twelve years. A practical and 

 effectual means of stamping out rinderpest, and of 

 Immunising cattle which have been exposed to infection, 

 has been found. Mules can be and are effectually 

 immunised against horsp-slckness, and there are good hopes 

 of the early discovery of a practical method of immunising 



XO. 2026, VOL. 78] 



horses against that disease. Although it has not been as 

 yet found possible to immunise stock artificially against 

 east coast lever, the investigations which have been made 

 into that disease have made it possible to recommend pre- 

 cautions, which have proved successful, for preventing the 

 disease from making its appearance on a f;irm, and have 

 demonstrated the possibility of clearing infected areas. A 

 practical method of vaccination against biliary fever, which 

 m donkeys, mules, and horses is stated to be a success, 

 has been discovered. The possibility of producing a serum 

 which is stated to have a strong preventive action in cases 

 of heartwater in cattle, sheep, and goats has been demon- 

 strated. .Methods ol inoculation against blue-tongue in 

 sheep, which are likely to prove to be of considerable prac- 

 tical value, have been discovered. It is scarcely necessary 

 that I should refer to the widespread confidence which is 

 felt, by those interested in pastoral pursuits, in the vaccines 

 against anthrax, quarter-evil. Cape red-water, and lung- 

 sickness, which are issued from the various Government 

 laboratories. 



As regards diseases and insect pests of plants, the plague 

 of the Dorthesia insect, which twenty years ago threaten^;d 

 to extinguish the cultivation of oranges in the Cape Colony, 

 and led to the destruction of great numbers of blackwood 

 trees and to the abandonment of that beautiful tree for 

 street planting, was stopped in 1892 by the introduction of 

 the Vedalla ladybird. The discovery of this remedy was 

 due to the scientific study of insects. Fruit trees infected 

 with scale insect can now be safely fumigated with hydro- 

 cyanic acid gas. This remedy is essentially the outcome 

 of scientific inquiry. The continued cultivation of the vine, 

 which was gravely threatened by the Phylloxera, lias been 

 made possible by the Introduction of the method of graft- 

 ing on " American stocks." This method, which is simple, 

 has been developed by means of an infinite amount of 

 close study and by innumerable scientifically conducted 

 c.vperimenls. Study of the locust problem has shown how 

 the great swarms of voetgangers, which cause such 

 enormous destruction of crops, and even of grass, can be 

 annihilated easily, and at relatively slight expense, by the 

 adoption of a method discovered and developed in .South 

 .•\frica. The entomologist, the chemist, and the engineer 

 have amongst them solved the problem of the codlin moth, 

 and it only remains for the horticulturist to apply effectually 

 the knowledge which they have gained in order materially 

 to reduce, or even to get rid of, the ravages of that pest 

 of our apple orchards. There is promise that the destruc- 

 tive mealie-borer may prove to be controllable by simple 

 means. This problem, as well as the problem of the fruit 

 fly, is now being investigated in the Government labora- 

 tory at Grahamstown ; and it does not seem too much to 

 hope that before many years have elapsed the scientific 

 plant-breeder will have succeeded in evolving varieties of 

 wheat and oats which will fully resist rust, whilst proving 

 quite satisfactory in other respects. 



Vast strides In the matter of the study of the hybridisa- 

 tion of plants, and in the selection and fixing of characters 

 of varieties, have been made during the last few years by 

 the application of new theories of the transmission of 

 characters, theories which were first formulated more than 

 forty years ago by Gregor Mendel to explain the results 

 which he obtained in crossing varieties of the sweet-pea 

 in his monastery garden. Mendel published the result of 

 his work In 1865, but until iqoi it appears to have been 

 completely lost to view. Probably the good .Abbot little 

 realised the profound importance of his deductions as 

 regards the realm of practical agriculture. Hybridising 

 used to be described as a game of chance, played between 

 man and plants. In which the chances were in favour of 

 the plants. Mendel's work changed the whole aspect of 

 the problem. His discovery, that in cross-breds the egg- 

 ceils and pollen-grnlns are pure with respect to the 

 characters which tliey individually carry, explains many 

 facts wiilch were previously mysterious, disturbs the founda- 

 tions of many current theories of heredity, and indicates 

 the possibility of picking out the valuable characters from 

 different varieties and of building up an Ideal type within 

 a reasonable time. It is on these lines that, as I under- 

 stand, the Transvaal plant-pathologist is now working in 

 his endeavours to produce rust-resisting wheats suitable to 

 South Africa. 



