146 TRANSACTIONS iSqq-'oO 



This they are not, however, and I cannot feel sure that the 

 chlorine they contain is not, at least in part, due to sewage. 



CHIvORINE 



24 

 56 



58 (in rock) 

 170 



195 

 240 



Two wells in this region answer to the type of mineral 

 springs. They contain respectively 3775 and 3700 parts of chlorine 

 per million. It is quite evident that this chlorine has a mineral, 

 and not a sewage, origin, and I mention them to show how mark- 

 ed a distinction exists between such wells, and the ordinary 

 domestic well. 



lyater in October, I collected, partly in person, and partly by 

 deputy, seventy samples of well-waters along the Montreal road, 

 through the villages of St. Joseph, Blackburn and Cyrville, and 

 the adjacent country. Of the wells less than 10 feet deep, eight 

 contained less than eight parts chlorine per million and 13 others 

 gave chlorine varjnng from 16 to 250 parts, six wells yielding more 

 than 100 parts per million. Most of these wells were so evidently 

 unprotected that I was prepared to find them dangerously con- 

 taminated, as the result shewed them to be. 



Of 31 wells h-aving a depth between 10 and 20 feet, only two 

 gave less than 10 parts of chlorine ; 14 gave more than 100 parts, 

 and 5 more than 200. There can be no doubt whatever that 

 most of this chlorine has a sewage origin. 



Of the deep wells, the following is the record : 

 DEEP WEI.LS 

 I 

 2 

 3 

 4 

 5 

 6 



9 

 10 



