1907.] on Certain Seasonal Diseases of the Slieep. 539 



to escape. It is often said tliat it seems to suffer from cramping 

 pain in the a])domen, but my own observation seems to point to the 

 symptoms of uneasiness beim; due, quite as much at least, to 

 feverishness, and to the animal being- in a half-delirious state. The 

 swelling of the abdomen is often not at all marked until after death, 

 when it ensues with great rapidity, a matter of a couple of hours 

 being sufficient to render the abdomen tense and tympanitic. When 

 inoculated experimentally, the subcutaneous areolar tissue of the 

 thighs and abdomen can be felt to crackle on pressure at the time 

 of death, and this also increases immediately after the animal has 

 died. In some cases, there is eyidence of diarrhoea — in fact, from 

 the empty condition of the bowel after death, I am inclined to 

 believe that diarrhoea or, at least, copious evacuation of the bowel, 

 must be of common occurrence. The urine is said to be scanty, and 

 dark-coloured, but I have not noticed, in cases where there was an 

 absence of haemorrhage into the muscles, or elsewhere, that the urine 

 contained in the bladder after death presented any abnormality. 

 Hogg relates that an animal, which he was carrying home on his 

 shoulders, vomited, but this must be a rare symptom, as the paunch 

 is invariably filled with food. 



The disease when inoculated usually runs a course of from five 

 to eighteen hours after the symptoms have declared themselves. 

 The most rapid case I have noticed was one in which the animal 

 lived for nineteen hours, dating from the time the virus was intro- 

 duced. Some natural cases are said to linger for a few days, but I 

 doubt if these are instances of Braxy. There is no more constant 

 sign of the disease than the extreme rapidity with which the fatal 

 issue ensues, and in this respect the malady has often reminded me 

 of Asiatic cholera. 



The incubation period cannot be determined in natural Braxy, 

 but in inoculation experiments I have found it to be generally from 

 forty-eight to sixty hours, often very much shorter. When the virus 

 is sporing, and is injected simultaneously with acetic acid, not only 

 does the attack prove more severe, but the incubation period is 

 diminished. 



The Organism icldch is the Cause of the Disease. — Throughout the 

 carcase of an animal dying from Braxy a vegetable micro-organism 

 is found usually in great alnmdance. The effusions into the various 

 serous cavities of the Ijody literally swarm Avith it, Init that poured 

 into the peritoneal sac ahvays contains it in greatest abundance. 



Not only, however, does it prevail in the effusions into serous 

 cavities, but it is also found, at least after death, in the blood, a fact 

 which is in a manner corrol)orated by the heart's chambers containing 

 gas. That the presence of the bacillus in the blood is not merely a 

 post-mortem phenomenon, is borne out by the observation that, in 

 cases where the animal had been dead only a very short time previous 

 to the making of the autopsy, and where as yet the carcase was quite 

 warm, gas escaped from the interior of the heart. In respect of the 



