202 OF THE BLOOD. 



justified in regarding it, then, as the special pabulum of those connective tissues, 

 whose physical offices in the economy are so important, whilst their vital endow- 

 ments are so low (CHAP. v. SECT. 1) ; and as serving, by its own formative 

 power, for the generation of these tissues, wherever and whenever there may be 

 a demand for them. On the other hand, there is a complete absence of evidence, 

 that the fibrin of the blood serves any special purpose in the nutrition of the 

 cellulo-albuminous tissues ; and there are various negative indications that their 

 generation and development do not depend upon its presence. For, in the first 

 place, there is evidence that a fluid destitute of coagulating power may serve 

 the general purposes of nutrition ; this being furnished, not merely by such 

 cases as that just alluded to ( 176), in which the circulating fluid was entirely 

 deficient in fibrin, apparently from defective elaboration ; but also by the results 

 of experiments on the introduction of defibrinated blood into the vessels of 

 animals which had been reduced to syncope by the withdrawal of blood, it hav- 

 ing been found, by Dieffenbach 1 and Bischoff, 3 that this operation immediately 

 restored the heart's action, and, with it, the general train of vital operations. 

 Further, although we are not justified in positively affirming that the fluid which 

 transudes the walls of the capillary bloodvessels, for the nutrition of the tissues 

 which they supply, is albuminous rather than fibrinous, yet there seems a strong 

 probability that such is the case j all non-inflammatory exudations being albumi- 

 nous, unless produced by an excess of pressure ( 227) ; and the fluid of the 

 lymphatics, which is probably the re-collected surplus of that which has thus 

 escaped, being so slightly coagulable, that we may fairly regard the presence of 

 fibrin in it as the result of the elaboration which it has undergone during its 

 passage through the absorbent system. Moreover, the formation of the Vege- 

 table cell takes place at the expense of an albuminous fluid, there being no 

 element in the juices of the Plant analogous to the fibrin of the blood ; and 

 although the endowments of certain parts of Plants are so peculiar ( 125), as 

 to prevent any such argument from possessing much weight, yet when it is con- 

 sidered that the great mass of the Vegetable fabric grows (like that of Animals) 

 at the expense of nutriment already prepared for it, and that the composition of 

 the Vegetable cell is essentially the same as that of the Animal cell ( 99), the 

 fact of the entire absence of any substance at all resembling fibrin in the vege- 

 table juices, and the corresponding deficiency of fibre-gelatinous tissues in their 

 solid fabric, may be adduced in confirmation of the views here advanced. 



193. Even if, however, we thus limit the value of Fibrin, as regards the 

 ordinary nutritive processes, to the maintenance of the gelatigenous tissues, we 

 still have to consider it as a most important component of the blood, and as 

 altogether different, in its relations to the living body, from those products of 

 disintegration which are destined to excretion ( 29, note}. For, putting aside 

 its presumed importance in maintaining that physical condition of the blood 

 which is most favourable to its free movement through the vessels, and to its 

 due retention within their walls ( 179), we find that it is entirely on the 

 coagulating powers of the blood that the cessation of hemorrhage even from 

 the most trifling injuries is dependent ; that the limitation of purulent effusions 

 by the consolidation of the surrounding tissue, and the safe separation of gan- 

 grenous parts, can only take place in virtue of the same property ; and that the 

 adhesion of incised wounds, still more the filling up of breaches of substance, 

 require as their first condition that either the blood, or matter exuded from it, 

 should be able to assume the state of fibrous tissue. The results of deficiency 

 of coagulating power in the blood are fearfully seen in that continued and 

 uncontrollable flow which takes place in Purpura, the blood not being able to 

 form a clot sufficient to fill up even the wound made by the scratch of a pin ; 



"Die Transfusion des Blutes," Berlin, 1828. 2 "Muller's Archiv.," 1835. 



