164 TRANSACTIONS OF THE CANADIAN INSTITUTE. [VOL. I. 



Kettle Well i. May loth, water showed as follows : — 



Litre i 320 



" 100 130 

 " 500 70 



May nth. Two litres containing sulphuric and carbolic acid poured 

 into the pump and left till following day. Then first water showed 

 strong carbolic reaction, and it could be noticed in water for about a 

 week, gradually becoming less intense. 



May 1 2th. Water apparently sterile. 



May 13th. Litre 500, 17 colonies. 



May 14th. All three (1-100-500 litres) contained colonies, and an 

 increase in number was noticed from that time in spite of the still 

 considerable amount of carbolic acid in water. 



May 19th. 10 litres — carbolic mixture poured in, pump tube brushed 

 out and water in well thoroughly mixed up. Results were even more 

 unsatisfactory. 



May 20th. Germs were in water in spite of intense odor of carbolic 

 acid water of a brownish yellow color, and ferric chloride test gave a 

 very marked reaction. 



May 2 1 St. Germs had increased to an extraordinary number in spite 

 of presence of considerable carbolic acid. Explains want of success in 

 above experiment as follows. 



In kettle wells, where there is always a considerable amount of water 

 present, a sedimentation takes place in the stagnating contents, and the 

 formation of a thick layer of mud on the bottom. In addition, there is 

 the formation of a much larger amount of the zooglea layer on the wall 

 than in the artesian wells. There is a very much larger number of bac- 

 teria in the second experiment than in the first, explained by the fact 

 that before the first experiment the well had stood untouched for a long 

 time, consequently the water had, as it were, been exhausted of all its 

 food material by the bacteria which were in it, and they had all been 

 converted into spore form, and had sunk to the bottom, forming a thick 

 layer in mud. 



The pumping out of the water had allowed fresh water to stream in, 

 and the stirring in connection with the experiment had disturbed the 

 materia] at bottom of the v/ell. 



The carbolic acid had destroyed the germs in the water itself, but had 

 not reached those in the mud at the bottom of the well. 



