PATHOGENIC BACTERIA IN DIFFERENT WATERS 303 



From these experiments it appears that in those 

 waters to which no additions of salt had been made 

 the cholera bacilli rapidly diminished in numbers, 

 whilst in the others their multiplication took place 

 almost in proportion to the quantity of salt added, this 

 being especially marked in the case of No. 17. 



It was also found that the addition of potassium 

 salts stimulated the vitality of this bacillus in a marked 

 degree, three drops of a 10-per-cent. solution of potas- 

 sium chloride inducing an increase in the numbers 

 present after twenty-four hours from 1,020 to 43,320 

 in the needle-loop. 



Experiments were also made with unsterile water, 

 as will be seen from the following table : 



TABLE II. Unsterile Well-water 



The author has unfortunately omitted to state the number of cholera bacilli introduced into 

 this water, but from his remarks it would appear that the initial number must have been largely 

 in excess of 216 per needle-loop. 



Thus in the unsterile water the cholera bacilli 

 quickly diminish, whilst the water bacteria rapidly 

 multiply. The addition of sodium chloride markedly 

 stimulates the vitality of the water bacteria, so much 

 so that when only one drop was added the cholera 



