77 0 MIDLAND COUNTIES VETERINARY MEDICAL ASSOCIATION. 
disease to others. This fact verified strongly an opinion gained 
from similar cases which I had long entertained, that as a rule 
cattle do not communicate the disease of contagious pleuro-pneu- 
monia to each other during the period of incubation. The other 
two cases led me to think that the really infectious period of this 
contagious bovine malady, as in human contagious diseases, was 
greater after the incrementory (incubative) stage had been passed. 
And here again a long list of personal records verified my thoughts, 
that slight and unrecognised attacks, and those making complete or 
partial recoveries in every stage of approaching convalescence from 
contagious pleuro-pneumonia, were the real sources of danger. 
From this time up to the present I have had many opportunities 
of strengthening my convictions by illustrative cases, two of which I 
will cite. Two years ago a neighbouring veterinary surgeon was 
called by a farmer to see one of two cows he had recently purchased, 
both of which had herded since the date of arrival (about seven 
days) with the other stock. The indisposed cow appeared to be 
excited, breathing quick, averse to food, &c. She was about her 
stated time for calving, and it was supposed she w r ould be better 
when she had done so, which she did the next day ; however, she 
gradually grew worse, and died in a few days. If her disease was 
recognised, the owner was never made acquainted with it. In about 
a fortnight from her death, the other of the two animals recently 
purchased was perceived unwell, and the services of the same pro- 
fessional man again required. It was thought she had taken cold ; 
was treated, and recovered, and in a short time turned back into the 
pasture, when lo ! and behold ! in about three weeks a cow two 
years on the farm was ill, and her disease said to be pleuro-pneu- 
monia, of which she died in a few days. Other cows similarly 
affected were soon found, onward it went, some died, some 
recovered, until nearly every head of cattle on the place had had its 
turn ; after which the animals on the next farm began to be attacked. 
It was stoutly denied that the second cow which recovered and 
was doing well ever, had the disease ; however I kept my eye upon 
her for nearly two years, and after much trouble I saw her 
slaughtered as a fat cow, November, 1869, when I found one lung 
firmly attached to the costae and other evidences of former pleuro- 
pneumonic disease. 
In the summer of 1868 I was called to see a cow belonging to a 
client of mine she was one of two purchased in the month of 
May preceding ; withan unfailing diagnostic aid in contagious pleuro- 
pneumonia I was soon enabled to decide the case to be so. The 
owner would not have her destroyed, but in a few days she died ; ten 
days afterwards the other cow was found ill from the same disease ; 
I treated her simply, she recovered, and in a week from the time 
she began to recover she became remarkably yellow on the skin, 
from which there arose a large amount of dandriff ; she was 
still “hoosking,” although her breathing and appetite were much 
improved. My client now wanted to have her back w'itli the rest of 
his cows, where both of these animals had been. “ No no !” said I ; 
