238 SCIENCE FROM AN EASY CHAIR 



purging. Microbes which are noted for other obvious 

 effects which they produce by the poisons they form in 

 man's intestines such as the microbe of typhoid fever 

 also produce cholera-like purging. 



But the name "cholera," or "the cholera," is now 

 applied without any further qualification to what would 

 be more correctly described as " Indian cholera," or 

 "epidemic cholera." It is a disease which first became 

 known to Europeans in India in 1817, less than a hundred 

 years ago. It resembles " simple " cholera in its general 

 features, but is usually much more violent in its attack, 

 and often causes complete collapse in two or three hours 

 from its onset, and death in as many more. The main 

 point about it is, however, that it is a quickly spreading 

 " epidemic " disease ; it invades a whole population, and 

 travels from place to place along definite routes. Al- 

 though the outbreak of cholera in India in 1817 was the 

 first to attract the attention of Europeans, it was nothing 

 new in India, and was recognised in distant ages by Hindu 

 writers. Its usual name on the delta of the Ganges is 

 " medno-neidan." Ninety per cent, of the population 

 perished of cholera in some districts of India in 1817, and 

 English troops were attacked by it with terrible results. 



Cholera gradually made its way in subsequent years 

 through Persia to Russia, and at last to Western Europe; 

 but it was not until late in the year 1831 that Indian 

 cholera arrived for the first time in England, and in the 

 following year it caused something like a panic. There 

 have been at least three subsequent outbursts of Indian 

 cholera (before that of the year 1908) which have reached 

 Europe, and two of these have reached England and 

 caused profound alarm and anxiety. That in 1854 

 reached us just before the Crimean War, and caused such 

 rapid and numerous deaths in London, especially in the 

 West End (St. James's, Westminster), that the corpses 



