THE MICROBES OF HUMAN DISEASES. 195 
The presence of the bacillus of typhoid fever in 
the air or in water has not yet been ascertained. 
Neither is anything known about the microbe which 
may be assumed to be the cause of typhus fever. 
VIII. Tart CHoLtera MICROBE, 
This terrible disease has its origin in Asia, where 
its ravages are as great as those of yellow fever in 
America. It is endemic or permanent in the Ganges 
delta, whence it generally spreads every year over 
India. It was not known in Europe until the begin- 
ning of the century; but since that time we have had 
six successive visitations, and it seems destined to 
replace the plague or black death of the Middle Ages, 
a disease which appears to be now confined to some 
few localities of the East.* 
In 1817, there was a violent outbreak of cholera 
at Jessore, India. Thence it spread to the Malay 
Islands, and to Bourbon (1819); to China and Persia 
(1821); to Russia in Europe, and especially to 
St. Petersburg and Moscow (1830). In the following 
year it overran Poland, Germany, and England, and 
first appeared in Paris on January 6, 1832; here it 
raged until the end of September. 
* See in the Annuaire de thérapeutique, 1885, Bouchardat’s 
account of cholera epidemics in Paris, together with remarks on the 
nature, the parasite, the hygiene. and the treatment of cholera, 
