The Vet. Book 



well known to be open to doubt, whilst a humid 

 soil, more especially when there is a moist warm 

 temperature prevailing, constitutes a predisposing 

 factor in determining the existence of anthrax, 

 providing there be a source of infection present, 

 such as an anthrax grave or a decomposing anthrax 

 carcase. Cape-horse sickness is most prevalent 

 during the rainy seasons and before the sun has 

 taken the dew off the grass. All diseases of a 

 parasitic nature are favoured by the presence of 

 moisture and warmth ; frosty weather constituting 

 a natural method of curtailing the spread of most 

 specific diseases of man and animals, though by 

 no means absolutely destructive of such. A clay or 

 retentive soil is one which rather favours disease, 

 whilst a sandy or gravelly soil confers some 

 measure of immunity. Drainage of land may be 

 either natural or artificial, but is essential where 

 animals are allowed to graze. The pollution of 

 streams by sewage water — more especially that 

 from mills, employing chemicals in the manu- 

 facture of their goods — generally exerts a very 

 detrimental influence upon stock drinking there- 

 from, whilst the careless distribution of material 

 from painters' pots frequently leads to the destruc- 

 tion of cattle. The same remark is equally 

 applicable to grazing horses and cattle in the 

 neighbourhood of lead smelting works, where 

 both acute and chronic forms of lead poisoning 

 occur. The careless distribution of sheep dipping 



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