Report on the Bacteriology of Water. 537 



Results of analysis expressed 

 in parts per 100,000. 



Total solid matter 8'80 " 



Organic carbon (by combustion), 0'623 



nitrogen ( ,, ) 0'049 



(by Kjeldahl process) . 0'044 



Ammonia (free) O'O 



(albuminoid) 0'023 



Oxygen consumed by organic matter. . . . 0'405 



Nitrogen as nitrates and nitrites 0'015 



Total combined nitrogen - 064 



Chlorine 0'8 



Temporary hardness O'O 



Permanent ,, 3'1 



Total 3'1 



e8 .i 



- cc . 



l a l 



? .- o 



r-s'f 



One part of this peaty water was sterilised by steaming, and 

 another part by filtration through a porous cylinder (Chamberland 

 filter), and each of these sterilised waters was divided into two parts, 

 which were respectively infected with the typhoid bacillus and with 

 the B. coli communis on 30.10.1893, thus : 



Agar cultivations of the typhoid bacillus and of the B. coli com- 

 munis, each twenty-seven days old and grown at 18 20 C., were 

 employed : 



Twenty needle-loops of the typhoid growth were thoroughly shaken 



up with 25 c.c. of sterilised water. 

 Ten needle-loops of the growth of the B. coli communis were 



similarly shaken up with another 25 c.c. of sterilised water. 



The peaty water was infected with the typhoid bacillus by adding 

 3 c.c. of the above water attenuation to 300 c.c. of the sterilised peaty 

 water, whilst for infection with the B. coli communis only 1 c.c. of the 

 water attenuation was added to 300 c.c. of the sterilised peaty water. 

 The infected waters were placed in flasks plugged with cotton wool, 

 and preserved in a dark cupboard at 10 12 C. 



The fate of the bacilli (typhoid and coli) in this infected peaty 

 water was then ascertained by means of periodical plate cultivations, 

 which yielded the following results : 



Steam-sterilised Peaty Water, infected 30.10.1893 with 



Typhoid bacillus. Plate cultivations made B. coli communis. 



30.10.1893 



- _ ^^_.^^___ 



1776 colonies from 13,321 colonies from 



1 c.c. (plates 1 c.c. (plates 



incubated 6 days). incubated 46 days). 



