December 7, 1905] 



NA TURE 



139 



His main thesis was that the scurvy of South Africa is 

 infectious in its nature, and probably of bacterial origin. 

 It is subject to seasonal variation; it occurs in epidemics 

 which vary in the intensity of their virulence. Its in- 

 cidence is greatest amongst the native races, and it has 

 a very high percentage of recurrences. An anti-scorbutic 

 diet does not prevent it. It occurs where the diet contains 

 a plentiful supply of fish and vegetables, and does not neces- 

 sarily occur where these foodstuffs are deficient. 



Dr. Mitchell gave a detailed history of the plague epi- 

 demics in Cape Colony. He showed that the plague in 

 every case was introduced by rodents, and suggested more 

 stringent measures to prevent the introduction of infected 

 animals. 



Dr. R. S. Black, formerly physician to the leper asylum 

 at Robben Island, gave an account of leprosy in South 

 Africa. He dwelt on the accumulation of evidence which 

 existed in favour of leprosy being an infectious disease, 

 and the absence of any data which had come under his 

 notice in favour of this disease being due to the eating 

 of fish. In the discussion which followed the paper Prof. 

 Sims Woodhead pointed out the importance to patients 

 themselves, and to the State, of removing any ambiguity 

 as to the infectious nature of leprosy. It could not be too 

 clearly understood by the native population that the policy 

 of segregation was not prompted by one of a number of 

 rival theories, but was the result of established facts. 



On August 19 some of those who had attended the 

 section enjoyed the hospitality of the Cape Government 

 at Robben Island, where they were shown the admirable 

 arrangements for treating the lepers. 



Johannesburg, August 29. — The proceedings of the sec- 

 tion opened with the president's address. This has been 

 printed in extenso in the columns of Nature ; it is there- 

 fore unnecessary to refer to it here further than to say 

 that it struck the key-note of the whole work of the day's 

 sitting. Colonel Bruce dealt very fully with the stock 

 diseases of South Africa from the purely scientific side. 

 Those whose papers followed (the Hon. George Turner 

 and Dr. Theiler) dealt with rinderpest and other stock 

 diseases from the point of view of the practical student 

 of the problems which these diseases offered to the farmers 

 and to the executive of the Transvaal. The urgency of 

 the situation which was caused by the rinderpest epidemics 

 and the success of the means which were used to cope 

 with them are shown, as Mr. Turner pointed out, by the 

 fact that 986,51s animals are estimated to have been saved 

 by inoculation. Roughly, four thousand five hundred litres 

 of serum have been used for the inoculation at a cost of 

 -I. 10s. per litre. In some herds the method of " simul- 

 taneous injection " of virulent blood and immunising serum 

 has been so successful that only 14 per cent, of the cattle 

 have fallen victims to the epidemic, whilst 1-3 per cent, 

 have been killed by the injection. 



Dr. Theiler's paper dealt with stock diseases generally ; 

 the fact, however, that his name is so intimately connected 

 with recent advances of knowledge into the etiology and 

 prevention of horse-sickness accentuated the interest of that 

 part of his communication which dealt with this disease. 

 Briefly summarised, horse-sickness especially occurs in 

 low-lying districts during the rainy season. Animals 

 are infected only at night. The infection ceases as soon 

 as the frost comes. The disease is inoculable in animals 

 of the same species, but is not contagious. Horse-sickness 

 is distinct from " blaau tongue " or catarrhal fever, which 

 closely resembles it in most of the above character- 

 istics. The virus of horse-sickness is easily destroyed by 

 desiccation, but it is not affected by cold. Both the above 

 diseases are conveyed from animal to animal by insects. 

 Veterinary Surgeon Spreuill has succeeded, by hyper- 

 immunising sheep with virulent blood, in producing a 

 serum which is efficacious in cases of "blaau tongue." 

 The author has achieved immunity against horse-sickness 

 in mules and horses by simultaneous subcutaneous injec- 

 tion of serum and intravenous injection of virus. 



August 30. — An interesting feature of the work of the 

 section, and one for which it is much indebted to the 

 officials, was a visit to the compound hospital, presided over 

 by Drs. Louis G. Irvine and Donald Macaulay. As an in- 

 troduction to the inspection, a paper was communicated by 

 Dr. Macaulay and Dr. Irvine upon the conditions of native 



NO. 1884, VOL. 73] 



labour in the mines. They pointed out the great difficulty 

 of persuading the native workers to care for their own 

 health, to take even the simplest precautions, for instance, 

 on coming up from the deep mining levels into the cold 

 air. The death-rate was much lower than formerly, but 

 it was still very high as the result of pneumonia and 

 phthisis. The main problem, however, is that of 

 acclimatisation. 



Other papers were read by Dr. Leingme on diseases of 

 natives, Dr. Maberley on the pharmacology of South 

 African drugs, and Prof. McKendrick, F.R.S., on the effect 

 of radium on the electric currents of the retina. 



September 1. — Prof. Waller, F.R.S., gave an account of 

 his recent researches into the means of estimating the 

 percentage of chloroform vapour in air by means of the 

 densimeter. He showed how frequently the cause of death 

 was due, not to idiosyncrasy of the patient, but to an 

 unsuspected increase in the dose of chloroform. This 

 might occur whatever method was used, but it was specially 

 likely to happen when the so-called " Edinburgh method" 

 of administration with a towel was used. His experi- 

 ments had shown in theory what had already been proved 

 by practice, namely, that a mask covered with donette 

 delivered the proper percentage of chloroform to the 

 patient, namely, 2 per cent. 



Dr. Pavy, F.R.S., read a paper for which the thanks 

 of the section are due to him in an unusually large 

 measure. The main thesis was based upon Dr. Paw's 

 well known view that the comparatively small molecules 

 into which the food is broken down in the intestine do 

 not exist in the blood as such. This view is the result of 

 so much practical experience of the treatment of diabetes 

 and of so much careful thought and accurate work that it 

 must always command the respect of physiologists if not 

 their adherence. The part of Dr. Paw's paper dealing 

 with the mechanism which exists for building up such 

 molecules as sugar into the larger molecules of which they 

 form but a small part was of a much more speculative 

 nature. The author's view was that this function was per- 

 formed by the lymphocytes, which took up sugar, &c, 

 much as haemoglobin acquires oxygen. The sugar is thus 

 built up into the molecules of living protoplasm, and is 

 subsequently imparted to the plasma and indirectly to the 

 body. 



Dr. M. Armand Ruffer gave a brief account of the 

 evolution of the present knowledge of immunity artificially 

 acquired. His own researches show that the serum of 

 rabbits injected with human, bovine, or ovine urine dis- 

 solves in vitro the red blood corpuscles of that species of 

 animals the urine of which has been injected. It is specific, 

 i.e. has no action on the red blood corpuscles of any 

 other species of animals. The author calls lysogen the 

 substance which, when injected, produces a haemolytic 

 scrum. Lysogen dialyses slowly, is not precipitated com- 

 pletely by alcohol, but wholly by saturation with ammonium 

 sulphate or lead acetate. Simple exposure to air for one 

 month or more destroys it, though it resists putrefaction 

 and is not wholly destroyed by a temperature of ioo° C. 

 Urine contains haemosozin or hremosozins, i.e. a substance 

 or substances preventing the action of haemolytic serum. 

 Some urines, e.g. human urine, prevent the action of serum 

 dissolving human, bovine, and ovine red blood corpuscles ; 

 others, e.g. bovine urine, act only on a serum dissolving 

 bovine red blood corpuscles. Dialysed urine is just as active 

 as ordinary urine. Haemosozin has practically the same 

 physical and chemical characteristics as lysogen. Bile 

 contains at least two groups of hemolysins, and at least 

 one haemosozin. This haemosozin is specific, i.e. pre- 

 vents the haMnolvtic action of the bile of that species of 

 animals from which the haemosozin was extracted, but not 

 the biliary hajmolysins of any other species of animals. 



The paper concluded by pointing out the necessitv of 

 making sera with isolated substances, and not with the 

 crude products of bacteria. By injecting crude products 

 it is more or less a matter of chance what the properties 

 of the serum will be. 



The proceedings ended at Johannesburg, as they had 

 done at Cape Town, with an expression of thanks to the 

 local officials of the section who had taken infinite pains 

 to bring the meetings up to the high level of interest which 

 they attained. J. Barcroft. 



