202 Dr. Anderson an the state in which Fibnn exists in the Blood 



white corpuscles stick because of their greater size, while the red 

 (known by their smooth outline, their central nuclei, elongated profile, 

 and, even under the microscope, pale yellowish colour,) rush beauti- 

 fully past them, like fragments of floating things carried against a 

 buoy moored in a strong tideway. As we watch the plasma it has be- 

 come partly solid, but no visible change appears ; the corpuscles re- 

 main quite still, and it is only by drawing across the glass a needle, 

 which carries the whole in a mass along with it, that we find that 

 they are engaged in a thin coagulum. There is then no running 

 together of the corpuscles ; but so far we are still in doubt whether 

 the clot may not be formed by their cohesion : the doubt is resolved 

 by simply continuing to look ; we have drawn aside the forming clot 

 before its solidification was complete ; and have left a clear fluid per- 

 fectly free of corpuscles of any kind, and yet in this again the coagu- 

 lation takes place ; it must, therefore, be from a solidification of the 

 previously fluid fibrin. 



So far my observations agree with those of Dr. Addison,* published 

 after mine had been made ; but he states that the fibrin solidifies 

 in the form of fibres, and figures these of a somewhat stellate or 

 spiculate appearance. In the existence of this sort of crystallisa- 

 tion I wholly disbelieve. I have repeatedly seen the whole field of 

 view occupied uniformly by the extremely delicate clot, so fine and 

 transparent as to be distinctly visible only when its edge was 

 drawn across the glass with a needle, and thus contrasted with the 

 remaining limpid fluid ; and of which the structure was so faintly 

 fibrous, that with the greatest difficulty, in a carefully modified 

 light, there could, with a power of 600 diameters, be just traced, 

 distributed equally over the whole surface, a most delicate striated 

 appearance. It is true that afterwards the coagulum becomes 

 fibrous, but this is the consequence of a subsequent contraction, the 

 nature of which has not been satisfactorily explained, but of which I 

 can say only this, that save its lessened size, and a slight increase of 

 the fibrous appearance, no change, by motion or otherwise, could be 

 observed in a coagulum prepared as above, and allowed to remain for 

 twenty-four hours in a covered glass cell under the microscope, till 

 it had fully contracted, and squeezed out all the serum from its 

 interstices. 



Moreover, I must differ in opinion from Dr. Addison, when he 

 advances it as ascertained, that the fibrinous spontaneously coagulable 

 liquid is formed within the white corpuscles, and appears on their rup- 

 ture only : there is no doubt some inseparable connexion between the 

 presence of these corpuscles and the existence of the fibrin of the 

 blood, for in determination of blood, and in inflammation, the increase 

 of the one keeps pace with that of the other : and it is possible that 



* Trans, of the Prov. Med. Assoc. 1843. 



