1863.] 587 



that they would, when moved, act as a churn on any blood contained 

 in the lower portion of tube. When the lower piece of tube was 

 fixed by means of a vice, V, the flexibility of the india-rubber per- 

 mitted the churn to be rotated so as to expose the blood to its in- 

 fluence. This having been arranged, I first poured in strong liquor 

 ammonite, so as to get rid of any slight acidity which the constituents 

 of the apparatus might be conceived to possess, and then, having 

 poured out the ammonia, filled up the apparatus with water, and 

 boiled the whole in a large glass test-tube till all bubbles of air, in 

 any portion of it, were expelled. Having then tied into a branch of 

 the carotid artery, C, of a calf a bent tube of small diameter, as re- 

 presented, and having permitted the blood to flow till it escaped 

 at the orifice of the tube, I compressed the artery and passed the 

 tube down through the water to the bottom of the apparatus, and 

 then let the blood flow again, which had the effect of displacing 

 all the water; and when the blood appeared at the top of the 

 apparatus, the tube was withdrawn, when two effectual clamps, 

 Cl, Cl, were placed on the vulcanized india-rubber connecting A 

 and B ; the india-rubber was then divided between the clamps, and 

 we had the state of things represented at the right-hand side 

 of the diagram. The upper portion of the apparatus, the orifice of 

 which was exposed to the air, was set aside and left undisturbed. 

 Having ascertained that the lower portion had been effectually 

 sealed by the clamp, and thus prevented from any opportunity of 

 escape of ammonia, I subjected it to the action of the churn for a 

 certain number of minutes. It so happened that the blood of that 

 calf was very slow in coagulating. I knew this from previous ex- 

 periments on the animal, and therefore continued the action of the 

 churn for a considerable time, viz. thirty-seven minutes. I then 

 found the wire enveloped in a mass of clot ; and examination of the 

 fluid residue with a needle indicated that the fibrin had been all 

 withdrawn from the blood on which the churn had acted. I did 

 not now examine the other portion of the apparatus, which had been 

 set aside ; but at the end of an hour and a quarter, when more than 

 double the time had elapsed, I investigated this, and found the blood 

 in it, for the most part, still fluid and coagulable. Thus the blood 

 in the churn, which, from the time it left the artery, had no oppor- 



