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living vessel was most striking; the red corpuscles presenting a degree of adhesiveness such as I had never before seen equalled, whether outside the body or within the vessels. When forced to separate from each other by pressure made upon the cover-glass, they became drawn out like threads of a viscid liquid before becoming completely detached. The animal had been suffering from a bad compound fracture in one of the wings. Whether the great adhesiveness of the red discs of the shed blood was due- to inflammation caused by the injury, or whether such a condition is normal to the bat, as it is to the horse and the ass, I do not know.
By such facts it seemed to be established that the stasis of the blood in an irritated area, that is to say, the accumulation of the blood-corpuscles, both red and white, in the vessels of that area, is due to a tendency on their part to adhere to each other and to the walls of the vessels; that they do this by virtue of an adhesiveness or viscidity which they do not manifest at all within the vessels of a perfectly healthy part, and which, while varying in degree with the severity of the irritation, never seems to exceed that which is observed in blood outside the body.[1]
What was it that induced the blood-corpuscles to assume this adhesiveness under irritation? It was clearly not the result of direct action of the irritant upon them. When the inflammatory congestion, as
- ↑ Vide "Phil. Trans.," 1859.