Wiat/wr, U'd/ff ixiid Disease. 29 



of water to disease is that wliich clinical experience has 

 given. As far V^ack as 1S4S and iS5<\ when cholera was pre- 

 vailing in London. Dr. vSnow noticed that in one neighbor- 

 hood, where many people were using water from a well, a 

 consideral)le proportion of them sickened and died from 

 cholera. He believed that it was due to contaminations from 

 cholera excreta, and proved great organic contamination. He 

 maintained that the contagium was particulate and living, but 

 methods now available were not so then. The repetition of 

 such sources of infection have been so frequent since that 

 the evidence is convincing to both the professional and non- 

 professional public ; jet such waters have been .so apparently 

 pure, that in the early experience of such cases, people would 

 insist upon using them. More than a hundred of such 

 demonstrations of the connection of impure water with 

 typhoid fever have occurred in England and the United States 

 alone. Dr. Walcott saj-s, in regard to the Merrimac River : 

 " There is nothing in the appearance or taste of the water to 

 deter a community from its use, nor does the chemical 

 analysis indicate a water too polluted for drinking." Yet the 

 following are his figures in regard to the two cities of Lowell 

 and Lawrence, situated on that river: "The average death 

 rate from typhoid fever for all the cities of Massachusetts, for 

 twelve years, from 1S78 to 18S9, was 4.62 per 10,000; for the 

 same period the rate in Lowell was 7.63 and in Lawrence 8.33 

 per 10,000. For the four years — 1886-89 — average rate in 

 Lowell per 10,000 is 9.55 and 10.30 for Lawrence; while in the 

 other cities in the vState the rate was 4.59. Scarlet fever has 

 been transmitted through milk, diluted with water, where 

 families have had scarlet fever, also diphtheria. 



Some years ago, when our Deer Creek was a center for pork 

 killing and packing, for two Winters there was prevalent an 

 obstinate and serious form of dysentery. A committee was 

 appointed by the medical society to report upon it. I was 

 chairman, and we found that the Deer Creek sewage was 

 being pumped into our reservoir, and that the disease pre- 

 vailed only among the consumers of the city supply ; others, 

 who were using other sources of supply, were exempt. 



Much more might be said on this particular branch of our 

 subject. We come now to new methods of water examina- 



