874 PHILOSOPHICAL TKANSACTIONS. [aNNO 1687. 



it was found that the iron in the open air had been l6 times more dissolved, 

 than the iron in vacuo. The second experiment is, that two equal quantities of 

 roses were put into two instruments for distillations, like each other ; but the 

 one was exhausted of air, and the other was full ; the distillation was abundantly 

 greater and quicker in the evacuated instrument, than in the other, although 

 they were both heated by the same warm water. It was also observable, that 

 the rose-water distilled in vacuo did congeal, which does not happen in ordinary 

 distillations. So it is plain, that in some circumstances the vacuum helps dis- 

 tillations, but that in other circumstances the compression of air is more advan- 

 tageous. 



Observations of what preternaturally occurred on opening the Body of Mr. Smith 

 of Highgate, July 6th, l687. Communicated by Dr. Edward Tyson, F. R. S. 

 N° 188, p. 332. 



In the first place, dividing the abdomen, immediately upon incision made into 



the peritonaeum, we discovered the bladder very scirrhous and thick, viz. ^ of an 



inch ; of a praeternatural figure, and distended to the size of a child's head : 



and at the entrance of the ureters, on each side, were two protuberances, of 



the size of a hen's egg ; the ureters were of the width of the small guts in 



children ; so that they could easily admit two fingers into their cavity. They 



were both replete with urine, or a serous matter; which, upon pressure, 



easily regurgitated into the kidneys, but would not pass at all into the bladder. 



The kidneys were of their natural size and figure ; but so emaciated, that they 



were rather large bags, than of a fleshy substance ; the cavity of the pelvis being 



so large as to contain above 3 ounces of water. But to return to the bladder ; 



therein upon opening we discovered a very strange sort of cysts or bags, of the 



exact figure of eggs, of several dimensions, some larger than goose eggs, others 



as large as hen's eggs, to the number of J.2 in all ; and about 8 of them whole 



and replete with a limpid serum : the coats of these bladders were some of 



them considerably thick, others very thin and tender ; all of them loose and 



free, without the least adhesion, either to each other, or to the coat of the 



bladder. There was little or no urine in the bladder, but what was contained 



in these bags. Nor could we imagine that this miserable patient could possibly 



make any water, but what happened on the breach of some of these watery 



tumours, when the bladder was crowded beyond its dimensions ; for that the 



passage by the ureters into the bladder was impervious : and though the ureters 



were full of serum, yet could none be forced into the cavity of the bladder. 



This liquor contained in these bags, we conjectured to be of the nutritious 

 juice of the body ; and on trial, by boiling a small quantity of it, we found it 



