ASIATIC CHOLERA 117 



and railroads. Infected individuals leaving the lo- 

 calities where they had contracted the disease, would 

 fall by the way, or recover before travelling any great 

 distance, if restricted to the methods of transportation 

 available before the introduction of steam as a motive 

 power for ships and railroad coaches. The fact that 

 cholera is carried from place to place by men, follow- 

 ing routes of travel, is well stated by the German 

 physician Griesinger. He says : 



" Cholera has never advanced like a broad stream inundating 

 entire countries at one time, bringing disease to all regions lying 

 parallel with each other, over a wide extent, but it always ad- 

 vances in relatively narrow lines from which usually, but not 

 always, lateral offshoots arise. In countries with a small popu- 

 lation we see constantly that this district corresponds with the 

 great lines of travel. If the disease oversteps high mountains, 

 if it passes through a desert, if it crosses the ocean, it always fol- 

 lows the lines of human intercourse, the post and military routes, 

 the caravan and sailing routes, etc. If it has broken out on an 

 island, then the first cases have always been in a seaport, never in 

 the interior." 



We now know definitely that the cholera germ is 

 carried from place to place by cholera-infected in- 

 dividuals, who harbour this deadly spirillum in their 

 intestines and leave it wherever the discharges from 

 their bowels are deposited. Mild cases of " choleraic 

 diarrhoea" are even more dangerous as regards the 

 propagation of the disease than severe and fatal cases, 

 for the infected individual may not suspect the nature 



