398 ON GENERATION. 



an animated similar part, composed of a body and a vital prin- 

 ciple. When this living principle of the blood escapes, how- 

 ever, in consequence of the extinction of the native heat, the 

 primary substance is forthwith corrupted and resolved into the 

 parts of which it Avas formerly composed ; first into cruor, after- 

 wards with red and white parts, those of the red parts that 

 are uppermost being more florid, those that are lowest being 

 black. Of these parts, moreover, some are fibrous and tough, 

 (and these are the uniting medium of the rest,) others icho- 

 rous and serous, in which the mass of coagulum is wont to 

 swim. Into such a serum does the blood almost wholly 

 resolve itself at last. But these parts have no existence 

 severally in living blood; it is in that only which has be- 

 come corrupted and is resolved by death that they are en- 

 countered. 



Besides the constituents of the blood now indicated, there is 

 yet another which is seen in the blood of the hotter and stronger 

 animals, such as horses, oxen, and men also of ardent constitu- 

 tion. This is seen in blood drawn from the body as it coagu- 

 lates, in the upper part of the red mass, and bears a perfect 

 resemblance to hartshorn -jelly, or mucilage, or thick white of 

 egg. The vulgar believe this matter to be the pituita ; Aristotle 

 designated it the crude and unconcocted portion of the blood. 



I have observed that this part of the blood differs both from 

 the others and from the mere serous portion in which the co- 

 agulated clot is wont to swim in the basin, and also from the 

 urine which percolates through the kidneys from the blood. 

 Neither is it to be regarded as any more crude or colder por- 

 tion of the blood, but rather, as I conceive, as a more spiritual 

 part ; a conclusion to which I am moved by two motives : first, 

 because it swims above the bright and florid portion commonly 

 thought to be the arterial blood as if it were hotter and more 

 highly charged with spirits, and takes possession of the highest 

 place in the disintegration of the blood. 



Secondly, in venesection, blood of this kind, which is mostly 

 met with among men of warm temperament, strong and mus- 

 cular, escapes in a longer stream and with greater force, as if 

 pushed from a syringe, in the same way as we say that the 

 spermatic fluid which is ejected vigorously and to a distance 

 is both more fruitful and full of spirits. 



