378 PHILOSOPHICAL TRANSACTIONS. [aNNO 17 18. 



distended to 8 or 10 times their natural size, were very black, and in the pelvis 

 of most of those glands in 2 cows, there was a yellow petrifaction, of the con- 

 sistence of a sand stone. Their intestines were the colour of a snake, their 

 inner coat excoriated by purging. Their lungs were much inflamed, with 

 several cysts containing a yellow purulent matter, many of them as large as a 

 nutmeg. Their flesh was extremely hot, though very little altered in colour. 



I have here only given a general account of the dissections, in the three 

 different stages of the disease ; in which the difference was but small ; but the 

 following cases being very extraordinary, I could not omit the mention of them, 

 viz. in one of them the bile was petrified in its vessels, and resembled a tree of 

 coral, but of a dark yellow colour, and brittle substance. In another there 

 were several inflammations on the liver, some as large as a half-crown, cracked 

 round the edges, and appeared separating from the sound part, like a pestilential 

 carbuncle. In a 3d, the liquor contained in the pericardium (for lubricating 

 the heart in its motion) appeared like the subsidings of aqua calcis ; and had 

 excoriated, and given as yellow a colour to the whole surface of the heart and 

 pericardium, as aqua calcis could possibly have done. 



In giving ray opinion on this distemper, I must beg leave to premise, that all 

 cows have naturally a purgation by the anus for 5 or 6 weeks in the spring, 

 from the frimness of the grass, as the cow-keepers term it; during which time 

 they are brisk and lively, their milk becomes thinner, and of a bluish colour, 

 sweeter to the taste, and in greater quantity : but the spring preceding this 

 distemper, was all over Europe so dry, that the like has not been known in 

 the memory of any one living ; the consequence of which was little grass, and 

 that so dry and void of that frimness which it has in other years, that I could 

 not hear of one cow-keeper, who had observed his cows to have that purgation 

 in the same degree as usual ; and very few who had observed any at all. They 

 all agreed that their cows had not yielded above half so much milk that summer 

 as they did in others ; that some of them were almost dry ; that the milk they 

 did give was much thicker and yellower than in other years. It was observed 

 by the whole town, that very little of the milk then sold would boil without 

 turning ; and it is a known truth, that the weakest of the common purges you 

 can give a cow entirely takes away her milk. From all which circumstances, 

 and several others of less moment that occurred during my daily conversation 

 at that time with cow-keepers, &c. I think it evident, that the want of that 

 natural purgation was the sole cause of this disease ; by producing those obstruc- 

 tions which terminated in a putrefaction, and made this distemper contagious. 



Cows are likewise subject to a purgation, though in a less degree, from the 

 same quality in the grass, about the latter end of September ; which is called 



