402 PHILOSOPHICAL TRANSACTIONS. [aNNO 1700. 



it to a breadth equal to what the fish gives it in swimming, in order to observe 

 the motion of the blood in the thus extended vessels ; I found that whereas 

 when the fish did not move, the small vessels received two or three particles 

 a-breast; the same vessels now stretched out with the tail-fin which they run 

 across, not only admit no more than one particle, but likewise the particles do 

 not move so fast as in the extended vessels ; and in some places these particles 

 are so separated, that one or two may lie in the intervals. In this observation 

 the particles appeared not perfectly oval, but sometimes round, and sometimes 

 in a shapeless figure ; arising from the little vessels being stretched to an unusual 

 length, by which they become narrower, and the particles being very pliant, 

 are pressed and squeezed out of their circular form. 



For further satisfaction I cut off a piece of the tail from several little butts, in 

 order to view the blood out of the vessels : when it appeared that the blood of 

 fishes consists of six little globular bodies, making up the particles as well as that 

 of men and other animals ; for I could observe several particles broken in 4, 5, 

 and some few in 6 pieces ; and it was very remarkable that some oval and 

 other figures became roundish, and at last perfectly round. 



The blood of a salmon appears blackish, by reason of a greater number than 

 ordinary of the reddening particles. I put some of this blood on a very clean 

 glass, and where the particles lay thin perceived them oval, nay, in several ovals 

 little globes, and in some few particularly six globes. Where these little globu- 

 lar bodies were crowded in upon each other, the particles of the blood were con- 

 gealed together, so that no ovals could be discerned ; nay the particles seemed 

 to be huddled up together so as that six of them had made a compound body. 



In fig. 5, pi. 12, ABCD represents the oval particles of the blood of a salmon, 

 that weighed above 30 pounds, ab represents the particles that appeared flat 

 and broad, but did not face the eye directly. Those about c came straight 

 upon the eye, and for the most part had a little clear sort of light in the middle, 

 larger in some than in others. These particles are heavier tlian the serous liquor 

 in which they swim ; and which, together with the particles, constitutes the 

 blood. I likewise put upon a magnifying glass the blood of a very small butt, 

 which was not mixed with any liquor, only the particles lay in their serum ; 

 which are represented fig. 6, between e and p. These particles, which are 

 distinguished by little shining spots in the middle, are delineated fig. 7, between 

 G and H. I also put the blood upon the glass to a greater magnifying glass, the 

 thinner moisture arising from the serous matter, and the oval-like blood being 

 exhaled ; so that some small oval particles were to be seen, that were so far from 

 running together, that they did not touch, and plainly showed that they con- 

 sist of 6 little globular particles, represented in fig. 8, between i and k. 



