1898] NOTES AND COMMENTS 3 
which he increased enormously by cultivating it in the peritoneal 
cavities of a series of rabbits. Other seruins have been prepared 
from other sources by different workers. But antitoxic action is 
subject to the laws of specificity to the same extent as toxic action. 
A given antitoxic serum will immunise against, or cure the disease 
produced by, just that one species of micro-organism which was 
employed in producing the serum. In the case of Streptococcus in- 
fection, it is therefore not remarkable that while in some cases a 
given serum will produce most striking curative results, in others it 
is absolutely powerless. In the present state of knowledge it is not 
possible to foresee which ease will benefit and which will not. But 
the fact that such differences exist may serve as a warning against 
the supposed unity of certain species of Streptococcus, maintained by 
some observers. 
THE EFFECTS OF TROPICAL CLIMATE 
THE exploration and first attempts at the administration of Africa 
have been attended with so serious a loss of life from disease, that 
it is not surprising that those interested in Africa should sometimes 
despair of its ultimate success. They throw the blame on that most 
indefinite of factors, the climate, and attempts to discuss tropical 
sanitation only too often degenerate into mere denunciation of that 
scapegoat. The afternoon meeting of the Royal Geographical Society, 
which assembled on April 27th to hear Dr Sambon’s paper on the 
possibilities of the acclimatisation of the white races in tropical 
regions, was no exception to the rule. Dr Sambon stoutly held that 
there is no reason why whites should not live and thrive in the 
tropical zone as well as they do in the temperate zones; but the 
meeting, in spite of Dr Manson’s powerful support of Dr Sambon’s 
propositions, would not be comforted. The discussion was interest- 
ing, as it could not fail to be when such authorities as Dr Manson, 
Sir John Kirk, Sir Harry Johnston, and Mr J. A. Baines took part 
init. But the discussion was disappointing as well, for the pessimists 
did not jom issue on the material point. They denounced the 
climate, even in places where it is described as “appearing delight- 
ful,’ and they pointed to past experience, as told by the mournful 
death roll or the degeneration of European races, such as the 
Spaniards in South America and the Portuguese in East Africa. 
But no one denies either the deaths or the degeneration. The 
question is whether they are due to unalterable factors of climate, 
or to organic diseases which may be met and defeated. Dr Sambon 
denied the climatic theory, and went through the climatic factors 
one by one, and showed that they alone are not injurious to health. 
He challenged those who hold that it is the climate which does the 
mischief to tell him how it acted, through what elements, and what 
