EFFECTS OF AN IMPURE SUPPLY OF WATER. 
461 
' has undoubtedly some effect upon animals. Mr. Stevenson, 
veterinary surgeon of Newcastle-on-Tyne, regards it as the most 
prolific source of abortion in cows, and abortion in ewes has 
been attributed to the same cause. {Journal of the Royal Agri- 
cultitral Society of England.) 
We have no idea how much it may be answerable for cases 
of intestinal irritation, such as diarrhoea ; or of obscure out- 
breaks of disease which we read of from time to time. It seems 
at least only rational to assume that it must have some evil 
effect, and as our knowledge progresses we shall have outbreaks 
of disease clearly attributable to this cause. We have at least 
clear grounds for stating that most of the specific diseases from 
which animals suffer may certainly be communicated through 
the water supply. I need only instance glanders, foot-and-mouth, 
cattle-plague, anthrax, and perhaps pleuro-pneumonia. 
The late Veterinary Surgeon J. H. Steel alluded to the sin¬ 
gular form of relapsing fever in equities, so thoroughly worked 
out by that gentleman, which he considers to have been intro¬ 
duced by impure water. All the animals attacked were watered 
at one tank and any fresh ones brought to it were certain to be 
affected. 
How far cases of sore throat, particularly that known as 
malignant sore throat, may be due to impure water, we have no 
knowledge. 
Lastly, water may be the medium, and perhaps in animals 
the most common medium, for the conveyance of the ova of 
parasites : tape worms, liver fluke, round worms, and thread¬ 
worms are undoubtedly conveyed in this manner. 
. Leeches may find their way into an animaPs nostrils 
through water, producing great inconvenience and hsemorrhage. 
The amount of organic matter in water given to animals to 
drink is often very high. I need only allude to the water- 
supply of farm-yards from pools and ditches : the water is stag¬ 
nant, putrid, swarming lyith animal and vegetable organisms, 
the result of the impregnation' with animal excreta and farm¬ 
yard refuse. 
