ON THE COAGULATION OF THE BLOOD 131 
In other words, he shows that the corpuscles do not act as living cells, but by 
virtue of a chemical material which they contain, which can be used in the state 
of solution, free from any solid particles whatever. He found also that the 
aqueous humour made a dropsical effusion coagulate, and that the same effect was 
produced by a material extracted from the non-vascular part of the cornea. 
Hence he regards the blood-corpuscles as only resembling other forms of tissue 
in possessing this property. These observations are extremely interesting, if 
trustworthy ; and that they are so I do not at all doubt, but having only read 
Schmidt’s papers within the last day or two I have not yet had opportunity of 
verifying his statements.’ 
It remains to be ascertained what share the material derived from the 
corpuscles has in the composition of the fibrine. Schmidt inclines to the opinion 
that the fibrine is probably composed, in about equal proportions, of a substance 
furnished by them and one present in the liquor sanguinis. If this be true, the 
action of an ordinary solid in determining the union of the components of the 
fibrine may be compared to the operation of spongy platinum in promoting the 
combination of oxygen and hydrogen. 
It may be asked, How comes it that when the blood of a horse is shed into 
a cup, the buffy layer coagulates as rapidly, or nearly so, as the lower parts rich 
in corpuscles ? 
This is indeed a question well worthy of careful study. We know that 
the liquor sanguinis left by the subsidence of the red corpuscles within a healthy 
vein is incapable of coagulating when shed, except in a slow manner, which is 
accounted for by the corpuscles that remain behind in it. Hence it appears 
that when the blood as a whole is shed into a glass, the agency of the ordinary 
solid leads the corpuscles to communicate to the liquor sanguinis, before they 
subside, a material or at least an influence which confers upon it a disposition 
to coagulate, though it still remains fluid for some time after they have left it. 
Just as we have seen that a very short time of action of the ordinary solid upon 
the blood as a whole is sufficient to give rise to coagulation, so we now see that, 
provided an ordinary solid be in operation, the presence of the corpuscles for 
but a little while is enough to make the liquor sanguinis spontaneously 
coagulable, though not immediately solidified. We shall see, before concluding, 
an illustration of the importance of this fact to pathology. 
* Since this lecture was delivered I have verified an important observation made by Schmidt, viz. 
that a given amount of corpuscles causes complete coagulation of only a limited quantity of hydrocele- 
fluid. From this he draws the inference that the action of the corpuscles cannot be of the nature of 
fermentation—the coagulative efficacy of the corpuscles being not continued indefinitely, but becoming 
exhausted in the process of coagulation. For Schmidt’s papers, see Archiv fiir Anat. Phys., &c., 1861 
and 1862. 
K 2 
