ABOUT CHOLERA 247 



in their antagonisms and co-operations in a healthy man, 

 that one cannot wonder at the timidity of the medical 

 man who hesitates to interfere with their conflicts and 

 established 'modus vivendi. Yet that seems to be the 

 direction in which action will have to be taken. It seems 

 likely that in different localities towns, forests, highlands, 

 lowlands, seaboards there are prevalent different microbes 

 which enter the bodies of human visitors and act as 

 disturbers of the native microbian flora previously estab- 

 lished in the stranger. 



That there are great differences in the microbian flora 

 (including herein minute moulds and fungi as well as 

 bacteria) of different localities, is shown by the great 

 experiment of cheese-making which mankind carries on. 

 Each kind of cheese Stilton, Cheshire, Dutch, Roquefort, 

 Gruyere, Gorgonzola, etc. is the result of the combined 

 and successive action on milk of a vast number of microbes ; 

 and it is the fact that the combination which produces any 

 given kind of cheese is only found and (unconsciously of 

 the exact nature of what he is doing) brought into activity 

 by man at certain places. You cannot make Cheshire 

 cheese in France nor Gruyere in Cheshire, and so on. It 

 is suggested and the matter is being pursued by experi- 

 ment and observation at the present time in France 

 that possibly amongst the other things which go to make 

 up the qualities of the air which agrees or disagrees with 

 one in any given locality are the local microbes. This 

 must not be regarded as a conclusion which has been fully 

 worked out it is an ingenious and promising suggestion 

 made by Metchnikofif as the result of some observations, 

 and will be fully inquired into. The fact which I have men- 

 tioned above (p. 242) that the presence of the microbe 

 Sarcina favours the growth of the cholera-bacillus indeed, 

 enabling it to grow and flourish in conditions in which it 

 was inert until the Sarcina was " sown " alongside of it 



