73(3 
Water in Rcla'ion to Health and Disease » 
is a fact we are obliged to admit, and it is tbis uncertainty in 
the effects of polluted water which renders it so hard to convince 
stockowners of the dangers which attach to it. If it acted with 
the certainty of strychnine, and the poisonous principle could be 
equally well detected by chemical analysis, conviction would be 
less difficult, and measures of prevention would be more scrupu- 
lously observed. But, as a matter of fact, we know compara- 
tively little of the real poison which lurks in impure water, and 
“ although the chemist may tell us with absolute certainty when 
water is safe, he cannot always tell us when it is actively 
noxious.” 
It is rarely the case that water is suspected of having any 
concern in the diseases of live stock, especially if from the same 
pump, or stream, or pond, the supply has been obtained — as 
it is often urged — for years without inducing violent sickness. 
Farmers are often heard to complain of their stock falling 
back in condition, and presenting an unthrifty appearance, not- 
withstanding an ample supply of wholesome food and the most 
healthy surroundings ; but it is not until some fatal outbreak of 
enteric disease, or acute blood-poisoning, appears to emphasize 
the long-abiding mischief, and the veterinary expert enters upon 
an inquiry, that an explanation is forthcoming. The low stand- 
ard of health, the lean and stunted gi’owth, which perhaps for 
years have rendered stock-keeping vexatious and unremunera- 
tive, are now seen to have had their origin in the same pollute 1 
water which determined the more fatal attack. 
The amount of danger attaching to the pollution of water 
with organic matter will depend upon — 
1. Whether the organic matter is animal or vegetable. 
2. The quantity of organic matter present. 
3. The activity of the state of putrefaction. 
Animal matter is more dangerous than vegetable, and, when 
in a state of decomposition, may develop putrefactive products 
as deadly as arsenic. 
Mr. Wynter Blyth, in his u Dictionary of Hygiene and 
Public Health,” says : “ The bad effects of human sewage on 
cattle appear to be nil.” Such a conclusion, however, is certainly 
not warranted by our experience. That cattle will, as he 
observes, “ grow and fatten on the most sewage-trodden soil ” 
is a fact in the experience of most practical men, but it is equally 
true that sewage under certain conditions, not only lowers the 
standard of health, but becomes distinctly poisonous. Moreover, 
the question has been recently brought forcibly before us as to 
whether human sewage may not be a means of spreading tuber- 
culosis in our dairy herds. 
