Introduction to the Study of Disease 



are not necessarily destructive. Such agents as 

 formalin, chinosol, corrosive sublimate, carbolic 

 acid, and chlorine gas, etc., will destroy most 

 organisms and their spores, hence the advisibility 

 for the employment of one of these agents in the 

 cleansing of places where these diseases have been. 

 The free admission of sunlight and pure air are 

 potent factors in the destruction of micro- 

 organisms ; and should never be excluded from 

 the stable, cow-house, kennels, etc., etc. All 

 specific diseases are capable of being carried 

 through a multiplicity of channels, such as cloth- 

 ing, hands, feeding and grooming appliances, 

 through the drinking water and food ; by rodents, 

 such as rats, mice, rabbits, and hares, etc., as well 

 as by flies, birds and insects in general. This is 

 one of the reasons why the spontaneity of disease 

 has been and still is, persisted in by those ignorant 

 of the methods of dissemination. 



Influence of Soil, Climate, etc 



Locality has a most important influence in 

 determining the presence or absence of certain 

 diseases, and it may be taken as a general rule 

 that upland pastures are much freer from disease 

 than the lowlands. Taking a couple of examples 

 familiar to all sheep raisers, we have only to 

 mention foot-rot and liver-rot. The prevalence 

 of these maladies on low-lying marshy soil is too 



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