SHERWOOD: DRINKING WATER ON TRAINS. 



19 



Altogether there were seventy-eight samples taken, and in 

 order to simplify matters these have been rean-anged into four 

 groups according to the degi'ee of pollution, beginning with the 

 worst samples in gi'oup I and ending with the purest water in 

 gi'oup IV. 



Group I includes all those samples ha\Tng at least 10 colon 

 organisms in 10 cc. of water, or 1 per cc. of the water examined, 

 and is as follows : 



GROIT I. 



Group II includes those having from 6 to 8 B. coli in 10 cc. of 

 water : 



GROUP II. 



Group III: There are fourteen samples having from 1 to 4 5. 

 coli per 10 cc. of the water. In two of them both Streptococcus 

 pyogenes as well as B. coli was present. 



Group lY: There ai'e forty-nine samples in which no B. coli 

 were present in 10 cc. of the water. 



In group I there ai'e five samples, or 6.4 per cent, containing 

 10 colon bacteria in 10 cc. of the water, or 1 per cc, with bacterial 

 counts ranging from 500 to 1800 per cc. In one sample Bacillus 

 pyocyaneus, the green-pus organism, was found to be present. 

 Watei-s in this group are decidedly unfit for drinking pm-poses. 



In group II there are nine samples, or 11.4 per cent, in which 

 there are 6 to 8 colon organisms in each ten cc. of the water, with 



