634- THE POPULAR SCIENCE MONTHLY. 



THE PILGRIM PATH OF CHOLERA. 



BY ERNEST HART, F. R. C. S., 



EDITOR OF THE BRITISH MEDICAL JOURNAL; CHAIRMAN OF THE ENGLISH HEALTH SOCIETY. 



WITH cholera steadily creeping toward our shores, and all 

 Europe standing armed against the invader, it becomes a 

 matter of the extremest interest to inquire how the disease escapes 

 from its home in India, under what influences it becomes able to 

 break its bounds, invade the outer world, and carry death and 

 devastation into countries where not only has it no natural home, 

 but where it is so far an exotic that even after repeated attempts 

 it fails to become acclimatized. 



India is the endemic home of cholera, and from some parts of 

 that great country it is seldom entirely absent. In 1881 there 

 were in India 161,000 deaths from cholera; in 1887, 488,000; in 

 1888, 270,000. The heat, the moisture, the necessity of drinking 

 stored water, and the habits of the people which make that water 

 foul, all combine to plant firmly in the district a contagium like 

 that of cholera. For the living infection, the contagium vivum of 

 this disease, enters man's body in the water which he drinks, 

 while in return it enters the water by means of the sick man's 

 discharges. A vicious circle is thus set up. Given a temperature 

 and perhaps a condition of water in which this contagium can 

 retain its vitality outside man's body, and a state of society in 

 which the fouling of the water and the drinking of it when foul 

 are daily habits, and we have before us the essentials necessary to 

 render the disease endemic. 



Whether this living contagious matter be a bacillus or a 

 spirocheete is almost beside the present question, and under what 

 circumstances of water and soil it grows and propagates, or mere- 

 ly rests, is again for our present purpose not of much impor- 

 tance. What is certain and what is of extreme importance is 

 that incontestably within the human body it grows enormously ; 

 that every individual sufferer from cholera is constantly discharg- 

 ing an untold multitude of contagious particles, which are capa- 

 ble of again setting up the disease afresh in any one by whom 

 they are swallowed ; and therefore that if these contagious par- 

 ticles are swept by rain showers into streams or wells, or if the 

 water in which linen soiled by them is washed percolates into 

 tanks or ponds, the water so fouled is specifically poisonous and 

 will produce cholera in those who drink it, just as arsenic mixed 

 in water will produce arsenical poisoning. 



It is a matter of surprise to many, who have the proofs of this 

 vicious circle nakedly before them, that the truth so long lay 

 hidden, and that even yet men who have lived much among chol- 



