OF THE OX. 143 



general conditions of the epizootia, the manner 

 in which the contagion is transmitted, and the 

 former state of health of the affected cattle. 



Thus an epizootia at the outset, either 

 when it has become general, or when it is at 

 its decline, does not always transmit typhic 

 miasma of the same virulent intensity, nor 

 does it always provoke in the frame a labour 

 of incubation which is invariable. The con- 

 tagion transmitted from animal to animal 

 living continually in the same stalls or sheds 

 is followed by an incubation more quick and 

 active than that which results from a chance 

 contact in the markets, or from a contagion 

 produced at a distance, by the transmission of 

 the miasmatic effluvium along the public 

 highways. 



Let us add to these considerations the rela- 

 tive state of each animal's health, and we shall 

 then perfectly understand that the incubation 

 must vary both in its continuance and in the 

 characteristics of its manifestation. In some 

 animals it scarcely betrays the derangements 

 produced by its morbid operation : they pre- 

 serve their appetite and their usual looks. A 

 close and attentive observation would alone be 



