674 PHILOSOPHICAL TRANSACTIONS. [anNO 1702. 



I took several pieces of the lungs, and pressed the blood and air out of the 

 vessels in which they lay, and was amazed at the vast number of bubbles of 

 air that came out of the vessels, some of which were so exceedingly small, that 

 they even escaped the sight of my microscopes ; those globules I supposed to 

 be contained in very fine vessels, and when the blood and the air were squeezed 

 out of that part of the lungs, where there were no great vessels, the remain- 

 ing ones, whose tunics were exceedingly fine, made together but a very small 

 portion of matter. 



I took also the unsoimd lungs of two other sheep, and found, in the 

 handling, that their parts were muoJi harder than others, that were not dis- 

 tempered, and that the matter or pus was stifFer or thicker in those lungs, 

 than in the abovementioned : looking on the external parts of these lungs, I 

 perceived in several places of them pellucid particles, which far exceeded in size 

 the air globules beforementioned. 



Being persuaded now that all the distempers in the lungs of sheep are occa- 

 sioned by the cold air wliich those beasts inhale, I asked two butciiers whence 

 they thought the diseases of their lungs to proceed, they answered, that the 

 sheep running in the meadows at the latter end of the autumn, and eating 

 grass that was either actually frozen or covered with cold dews, was the reason 

 their lungs were thus spoiled ; and that the same happened sometimes in May. 

 But for my part, I rather conclude that the frozen grass does not hurt their 

 lungs, but stomachs, and that the cold air affects their lungs. Knowing 

 that our butchers fetch abundance of f;it sheep from Brabant, and that those 

 sheep are driven every morning into the field, and folded every night by their 

 shepherds ; and that our sheep, on the contrary, are brought into the meadows 

 in May, and there left till it snows and freezes ; I asked the butcher whether 

 the Brabant sheep had such bad lungs as ours ; and was answered, seldom or 

 never. From whence I was still better satisfied that the diseases in the lungs 

 of sheep, and especially of such as lie in the field in the long cold nights, were 

 occasioned by nothing else but their drawing in the cold air. I further asked 

 whetl>er such sheep were fat while they were kept up, and whether they could 

 distinguish while living which of them had bad lungs ; to which they answered, 

 that those whose lungs were touched, never increased in fat alter they were 

 stalled ; and that within a fortnight's time after they had been shut up, and fed 

 with beans, in order to Aittening, the distemper usually disclosed itself, by their 

 coughing, and therefore they always killed those sheep first. 



Now if we allow that the cold air is so prejudicial to the lungs, we ought not 

 to wonder if such an inconvenience, as we call a cold, comes upon them. And 

 I am of opinion, that in a long cold winter the lungs may be so much in- 



