Dr. E. Klein on the Smallpox of Sheep. [June 

 TABLE III. (continued}. 



IV. " Research on the Smallpox of Sheep." By E. KLEIN, M.D., 

 Assistant Professor at the Laboratory of the Brown Institu- 

 tion, London. Communicated by JOHN SIMON, F.U.S., 

 D.C.L., Medical Officer of the Privy Council, &c. Eeceived 

 June 11, 1874. 



Variola ovina, or smallpox of sheep, is a disease which, although it is 

 not communicable to man, and possesses a specific contagium of its own, 

 very closely resembles human smallpox, both as regards the development 

 of the morbid process and the anatomical lesions which accompany it. 

 This correspondence is so complete, that it cannot be doubted that the 

 pathogeny of the two diseases is the same. The present investigation 

 was therefore undertaken in the confidence that the application of the 

 experimental method to the investigation of the oviue disease would not 

 only yield results of value, as contributory to our knowledge of the infec- 

 tive process in general, but would throw special light on the pathology 

 of smallpox. 



The paper consists of four sections. In the first, the author gives an 

 account of his experimental method, which consisted in communicating 

 the disease by inoculation to a sufficient number of sheep, and in investi- 

 gating anatomically (1) the pustules produced at the seat of inoculation, 

 and (2) those constituting the general eruption. The lymph employed 

 was obtained by the kindness of Prof. Chauveau, of Lyons, and Prof. 

 Cohn, of Breslau. 



In the second section, the organisms contained in fresh lymph, and the 

 organic forms derived from them by cultivation, are described. The 

 author finds that fresh lymph contains spheroidal bodies of extreme 

 minuteness, which correspond to the micrococcus of Hallier and to the 

 spheroids described by Cohn and Sanderson in vaccine lymph. It also 

 contains other forms, not previously described, which in their develop- 

 ment are in organic continuity with the micrococci. 



The third section contains a complete anatomical description of the skin 



