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the large fpace of air wliicli in the large tube occupied four inches 

 and two thirds, liad lo efcaped out of the glafs, that in the fmall 

 tube, from C towards E, there only remained of it the fixth part of 

 an inch. So that, according to my computation, the air in this 

 blood only occupied the one two thoufand three hundred and fe- 

 venty-fixth part of the bulk of the blood from which it was ex- 

 tracfted. 



I then went to a butclicr's, at the time I knew he was about to 

 kill a calf, in order to extradl the air from the blood while it was 

 yet warm ; and for this purpofe, 1 took with me my inftruments, 

 and alio a glafs veird two inches diameter, and eight inches deep, 

 in order to catch the blood as it ilfued from the vellels of the ani- 

 mal ; which having done, I put fome of it, as foon as poffible, into 

 my glafs pump, and treated it in the fame manner as before de- 

 fcribed, and I immediately faw feveral air bubbles arife, which 

 when they came to the furface, became very large. I alfo faw th(^ 

 blood fmk in the glafs tube from C towards B, fo that the tube was 

 filled with air to the height of five inches. Before I began my ex- 

 periment, I had accurately obferved what fpace of air was in the 

 fmall tube when I had clofed its orifice at D, by the means of fire.. 

 Upon drawing out the pifton as llowly as pofliblc, I faw all the fub- 

 tile air, which as I before mentioned, had filled the glafs tube 

 five inches from C towards B, had either efcaped out of the glafs 

 or returned into the blood ; for I could not perceive any the leafl: 

 increafe of air in the fmall glafs tube from C to D. 1 then opened 

 the glafs tube at D, and poured out all the blood as carefully as I 

 could, and then put into it a frefh portion of blood, and repeated 

 my former method of drawing out the air ; and then I faw that the 

 glafs tube from C towards B, being about five inches, was filled 

 with air, and that fome air bubbles arofe out of the blood, which 

 were very large. After I had very gently drawn out the pillon, I 

 faw that the air in the fmall tube was increafed by the addition of 

 two air bubbles covered with fome blood, neither of which bubbles 



