CAUSES OF DISEASE. 17 



to do its work witli greater ease, and to last longer than animals 

 deprived of so necessary an element as water. 



Water containing organic impurities, or too hard from the 

 over-abundance of earthy salts — that is to say, water con- 

 taining more than twelve degrees of hardness — is apt to induce 

 disease. 



Burton, in First Footsteps in Africa, says, at Zeyla, a large 

 Somal town on the East Coast of Africa, all the pits within the 

 walls supply brackish or bitter water, fit only for external use, 

 and that is the reason why vegetables are unknown, and why 

 a horse, mule, or even a dog, is not to be found in the place. 



Organic impurities, either suspended or in solution, and more 

 particidarly during the hotter months of summer, are apt to 

 induce diarrhoea, anthracoid and putrid diseases, which may 

 prove fatal. Animals certainly seem to become habituated to 

 impure water, and sometimes prefer it to that which is clean 

 and wholesome, but even these are not exempt from its evil con- 

 sequences ; and indeed the very depravity which leads them to 

 prefer what is so unnatural may be looked upon as of itself a 

 diseased condition. It may, however, be stated that there seems 

 to be a resistance, particularly in cattle, to the ill effects of 

 water contaminated with vegetable products, whereas, if these 

 be of animal origin — human ordure, decomposed blood, milk, 

 &c. — disease is almost certain to follow. Continual drinking 

 of very warm water is said to induce disease. 



But, as a rule, however, pure water may with benefit and ad- 

 vantage be allowed in such quantities as the animal seems to 

 require, taking its condition into consideration at the time. If 

 it be heated or exhausted by work, water must be supplied 

 in moderate and repeated quantities, and not too cold, until 

 its thirst is assuaged, or enteritis, diseases of the skin, or 

 inflammation of the feet, may result. With this exception, I 

 repeat that water ought at all times to be freely but judiciously 

 allowed. 



Water in the form of dew or hoar frost is believed to be a 

 cause of disease. It is very possible, if a very hungry animal 

 were to eat dew-covered grasses ravenously and quickly, that 

 digestive disturbances might arise ; but I fail to see how food, 

 masticated and retained in the mouth until its temperature is 

 elevated almost as high as that of the body, can be inducive of 

 disease. Dr. Fleming tells us {Sanitary Science and Police) 



c 



