598 Anatomy, Physiology, mid Pathology of the 



the malady was centred In the lungs ; and its acute symptoms 

 were preceded by a dry and husky cough, lasting from " a fort- 

 night to three weeks." In the second stage, he says — 



" They begin to forsake their food, and if they be milch-cows their milk 

 dries up — the fever, which was before obscure, begins now to be very per- 

 ceptible : the cough increases, they breathe with great difficulty, and the 

 eyes and nostrils in many of them begin to run with a thick and sometimes 

 fetid rheum ; the body grows hot, and the pulse is very full and hard. In 

 three or four days after their milk is gone off, and they have ceased to eat 

 and chew the cud, a purging most commonly comes on. The stools are 

 at first thin and watery, soon afterwards they grow slimy and fetid, and 

 sometimes they are mixed with blood. The purging continues for a week 

 or more, if the cattle live so long ; but if at the end of six or seven days 

 it begins to abate, and the excrements grow more solid, it is a token of 

 their recovery. The difficulty of breathing does not seem to be relieved 

 by this discharge. When the disease has been of long continuance, the 

 body has sometimes swelled extremely, either before or immediately after 

 death, and even to such a degree as to burst the paunch ; but in those 

 which have died early in the disease, the body has seldom or never been 

 known to swell. If the cattle begin to swell, and their flesh grow cold 

 towards the end of the disease, it is a certain sign of approaching death. 

 The continuance of the disease is very uncertain and precarious, for many 

 have died in two or three days after the fever has appeared, others have 

 lived six or seven, and some even twelve or fourteen days." 



This graphic account of the symptoms of the epizootic observed 

 by Dr. Barker, agrees in many essential particulars with those of 

 pleuro-pneumonia ; as is likewise the case with the post-mortem 

 appearances, which he describes as follows : — 



*'Upon opening the bodies of several which have died of this disease, 

 I have constantly found the blood-vessels of the lungs stuffed up and dis- 

 tended with grumous or coagulated blood, and the bronchia or air-vessels 

 so much inflated as to make the bulk of the lungs appear much larger 

 than usual. And though some of these cattle were opened before the body 

 was cold or the blood congealed in the other vessels, yet in those of the 

 lungs it was constantly found to be coagulated to such a degree as not to 

 flow out of the vessels upon cutting them."* 



The lesions here spoken of, as well as the symptoms, bear so 

 striking an analogy to those of the present malady, that I am most 

 strongly inclined to believe it to have been pleuro-pneumonia which 

 thinned the herds of the British agriculturist rather more than 

 100 years since; and it follows that it had so long disappeared 

 from among us, as not to be recognised in its recent outbreak. 

 If therefore I am right in the conjecture that the disease is not 

 in reality new, it is evident that certain causes, of which we are 

 now ignorant, came into operation and produced its withdrawal ; 

 and we are thereby encouraged to hope that ere long it will 

 assume a milder type, and ultimately cease altogether. 



It has already been stated that pleuro-pneumonia was preceded 

 by the affection vulgarly called " the old epidemic," in which 



* An Account of the present Epidemical Distemper amongst Black Cattle. Lon- 

 don, 1745. 



