Inoculation for Pleuro-Piieumonia in Cattle. 



as many as a dozen svperjicial punctures clustered together on the 

 labia oi perineum, or more distant placed on the tail, were made 

 with a grooved needle ; in each case the material used being, as 

 before, the serous fiuid from a diseased lung. As we had anti- 

 cipated, this method failed in every case. 



It is necessary here to state that one of the cows, which, from 

 the date of her admission, three weeks before, was suspected to 

 have the disease Pleuro-pneumonia incubated in her system, 

 from her peculiar cough and other symptoms, fell ill on the day 

 but one succeeding this inoculation. The animal bore up under 

 the depressing and destructive influences of the disease in its 

 active form for the somewhat lengthy period of twelve days, when 

 death put an end to her sufferings. The post-mortem appearances 

 agreed in every particular with those seen in similar cases. 



Jan. Qth, 1853. — The five cows were again inoculated in a 

 manner somewhat modified from the former. The skin of the 

 perineum was scratched with a lancet, sufficiently deep to cause a 

 very slight oozing of the blood from the numerous erasions, and 

 then upon these places a portion of diseased lung, laell charged 

 with serous and fibrinous effusions, was rubbed for the space of two 

 or three minutes. The cases were most assiduously watched, so 

 that the slightest indication of the action of the fluid, if specific, 

 would have been observed, but nothing took place even from 

 this plan of operating. 



\Ath. — We determined to give trial once more to simple erasions 

 of the cuticle, and to-day inoculated the five cows belonging to 

 Mr. Paget, together with another cow admitted into the infirmary 

 for mammitis, and also a heifer under our care for lameness. 

 Groups of erasions, varying in number from twelve to twenty, 

 were made on the labia, perineum, and under surface of the tail in 

 each animal, and upon these the serous exudation was rubbed with 

 the finger for not less than from four to five minutes. No 

 specific effects followed. 



20?^. — Inoculated each of three of the cows again, which had 

 been chiefly the subjects of the foregoing experiments, with two 

 deep punctures made with a grooved needle, and the two others 

 with four superficial punctures, all of which, like the preceding- 

 inoculations, also proved abortive. 



It appears pretty certain from these experiments that slight 

 punctures, and also scratches of the skin, will invariably fail ; a 

 fact which of itself is almost sufficient to disprove the existence 

 of any " special virus " being contained in the exudations from an 

 affected lung. Every person of experience in these matters 

 knows full well that success of inoculation, both with regard to 

 the local and constitutional declaration of the symptoms, depends 

 on the smallness of the quantity of the virus employed, and the 



