ANALYSES OF WELL, SPRING, MINERAL AND ARTESIAN WATERS. 81 
Class II. Comprehends the genera] drinking waters yielding 
‘05 to :10 parts per million of albuminoid ammonia, and 
any water falling into this class is organically safe. 
Class III. Comprehends the dirty waters, and is characterised by 
_ yielding more’ than ‘10 parts of albuminoid ammonia per 
million. Free ammonia however being absent, or very 
small, a water should not be condemned unless the albu- 
minoid ammonia reaches something like :10 parts per 
million, when it becomes a very suspicious sign, and over 
-15 parts per million is sufficient. to condemn a water. 
The absence of chlorine, of more than one grain per gallon, is 
a sign that the organic impurity is of vegetable rather than of 
animal origin; but it would be a great mistake to allow water 
highly contaminated with vegetable matter to be taken for 
domestic use. *In the Leek Workhouse there has been for years 
past a general tendency to diarrhcea, which could not be accounted 
for until the water was examined, and shown to be loaded with 
vegetable matter. The water was almost free from chlorine, con- 
taining only ‘5 grains per gallon. A well on Biddulph Moor a 
few miles from Leek, yielded -05 grains per gallon, and -03 “‘free” 
and -14 of albuminoid ammonia per million. The persons who 
were in the habit of drinking this water suffered from diarrhea. 
Valuable as is the chemical analysis of water, the information 
acquired is not an unfailing test as to dangerous pollution, and 
the sample under analysis may be found to pass the chemical 
analysis, and yet may contain the germs of disease. It is probable 
that cholera, typhoid fever etc. are frequently contracted by drink- 
ing such waters, containing prossibly the minutest trace of the 
excreta of persons suffering from these diseases. 
_ The standard of purity of waters is one which I hope will be 
soon taken in hand in the Colonies, as many of the waters are of 
a totally different character from these examined in England, and 
for which the basis of the standard in use is taken. 
* Water Analysis—Wanklin, p. 49. 
F—June 1, 1892. 
