70 SMALL I'OX L\ SIIKKP. 



fectcd sheep from the comniencenient of their ilhiess. 

 These three animals were attacked with an aggravated 

 form of the small-pox, which rendered their recovery 

 very douhtful, and one of them died. 



Variola ovina, like its prototype in man, is produced 

 by two separate causes, exposure and inoculation : 

 which circumstance has induced pathologists to divide 

 the small-pox into natural and 'inoculated. Our expe- 

 riments verify the propriety of this classification, but 

 they do not establish the general opinion to be cor- 

 rect, that the foraier is more fatal than the latter ; this 

 may, however, depend on the manner in which they 

 were carried out, as in every instance when we attempted 

 to propagate the disorder naturally, we limited the time 

 of exposing the animals to the contagion, and subse- 

 quently kept them apart from the infected. The 

 natm-al disease has been fearfully destructive in this 

 country ; and further experience may prove that, of 

 the two varieties, the inoculated is the least fatal. 



The affection admits also of a division into distinct 

 and conjluent : in the former, the papulae, although 

 numerous, do not inosculate; but in the latter they 

 run together, and produce large accumulations on 

 many parts of the skin. The danger to the patient 

 being very much increased when confluent papulae 

 exist, has led several of the continental ^witers to call 

 this kind the malignant, and the other the mild small- 

 pox. Many reasons can be assigned for confluent 

 variola being so fatal, besides the augmentation of the 

 local effects observed during its progress. The malady, 

 when it takes on this character, does not pass so regu- 

 larly through its different stages ; vesication is delayed ; 

 and imtil vesicles form on the papulae, the variolous 



