Inoculation for Pleuro- Pneumonia in Cattle. 



259 



minuteness of the puncture by which it is introduced into the 

 system. 



The virus of Pleuro-pneumonia, if the exuded fluid may be so 

 called, would not, in our opinion, as an animal poison, be an 

 exception to the law which governs the extension and repro- 

 duction of such poisons. It was clearly ascertained with regard 

 to the small-pox of sheep, at the time of its great prevalence, that 

 inoculations which were made by deep punctures and the intro- 

 duction of three or four ordinary drops of the virus, destroyed 

 many scores of these animals before the pock could be developed 

 on the skin. Success here depended, as in all other cases, on the 

 rules which we have described as applicable to the puncture and to 

 the inoculating material. With inoculations for the prevention of 

 natural Pleuro-pneumonia the very reverse obtains ; success is 

 connected with deep wounds and the employment of three or four 

 ordinary drops of fluid. To return, however, to the experiments ; 

 for these things will again present themselves for our investiga- 

 tion. 



— Inoculated three of the cows by making an incision 

 through the skin, just below the labia of each, and inserting into 

 the wounds a small quantity of serous exudation from a diseased 

 lung, using for the purpose a little friction v/ith the point of the 

 scalpel. 



Feb. 1st. — A slight tumefaction exists around the wound in 

 one case. The lips of the other incisions are thickened, but 

 otherwise free from swelling. 



2nd. — A small pustule has formed by the side of the incision 

 vvhich was yesterday tumefied ; but the adjacent skin is free from 

 undue redness. Scabs exist on the other wounds, which are now 

 swollen and approaching to suppuration. 



?>rd. — Suppuration is established in all the cases. The tume- 

 faction around the incisions is very slight, and the redness 

 scarcely perceptible. 



To-day we ?'e-inoculated these same coics, by making clean in- 

 cisions through the skin about half an inch long and about three 

 inches below the others, into which was inserted with the point 

 of the scalpel a little of the purulent fluid taken from the original 

 inoculated places. 



Ath. — ^The pus discharged from the original wounds is of a 

 good colour, and the general condition of the parts does not indi- 

 cate any interference with the healing process being quickly 

 accomplished. 



bth. — The swelling around the second-made incisions is more 

 than we have before seen. The parts are sore when pressed, and 

 it is evident that the wounds will quickly suppurate. 



1th. — Pus is being discharged from the wounds ; it is vrhite, 



