OF THE OX. 115 



of cattle from those countries which are consi- 

 dered as the permanent focus of typhus, has 

 from time to time transported the miasmatic 

 germs of this malady into England, although 

 the virus did not take effect on British cattle 

 at those periods, for want of one or other of 

 the conditions necessary to its generation and 

 development. 



We may likewise infer, and a watchful ap- 

 preciation of the facts contained in the ve- 

 terinary medical journals would show that this 

 opinion is not unfounded, that the special 

 disease which constitutes this typhus (similar 

 in that respect to epidemic diseases), may de- 

 velop itself in one beast hy accident, sponta- 

 neously, sporadically that is to say, without 

 immediate contagion ; in a word, apart from 

 those epizootic conditions which alone render its 

 propagation possible. To be brief, we think 

 that an isolated case of cattle typhus may by 

 chance be detected, when there is no epizootia 

 prevailing to account for it, just as we occasion- 

 ally meet with cases of typhus or cholera among 

 men during seasons absolutely free from these 

 epidemics. It would not, therefore, appear to 

 us altogether impossible, that under the in- 



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