LANCASHIRE VETERINARY MEDICAL ASSOCIATION. 
621 
great quantity of citron-coloured fluid. Having become more dense 
and friable, it adheres to and confounds itself with the exterior 
membrane of the vessel. 
This membrane is itself thickened, infiltrated with serosity, 
becomes more friable, and confounds itself — to the extent that 
there is no longer any marked point of separation between them — 
with the central membrane, which assumes precisely the same 
characters ; but — and it is of the highest importance to note this, 
in order to study the consecutive phenomena — the internal mem- 
brane of the vessel does not undergo any modification. It preserves 
all its white, pearl-like appearance, and its polish. The most 
minute inspection will not demonstrate the smallest vessel developed 
in its substance. 
The clot which the vein contains is jet black and adheres 
already, by its whole periphery, to the internal membrane, to which 
it seems fixed, as if there were a true agglutination between them , 
and it is a remarkable fact that this adhesion is stronger in propor- 
tion as we examine it near the ligature. 
If we dissect the clot, we shall find that it has already begun to 
undergo some modification. It seems to be composed of the super- 
position of numerous concentric fibrinous layers, which, by a tolera- 
bly careful manipulation, can be perfectly disengaged from each other. 
If we follow, in a series of experiments, the different phases of the 
phenomena of the inflammation of the vein, and the disorganization 
of the clot which it contains, we shall see that, in proportion to the 
time which has elapsed since the application of the ligature, the 
exterior cellular tissue of the vein becomes condensed as it gradually 
and intimately mingles with the external and central membranes of 
the vessel, so that, about the 20th or 25th day, they resemble a 
white indurated tissue, creaking under the knife. Still the internal 
membrane preserves all its normal characters ; and if there were not 
a greater degree of whiteness resulting from its transparency, which 
permits us to observe its subjacent white tissue, we should not be 
able to discover any difference, even after the 30th day of the 
application of the ligature, between this membrane and that of a 
healthy vein. 
As for the clot, in proportion as time passes on its arrangement in 
concentric layers becomes more and more evident. It diminishes in 
volume on account of the absorption of the liquids which impregnate 
it ; it changes its colour, and becomes of a fibrinous yellow hue by 
the disappearance of its colouring matter, and it adheres still more 
intimately to the internal membrane of the vein. 
Such, rapidly described, are the phenomena which take place in 
a vein which is the seat of adhesive or cicatrizing inflammation ; but 
there are some different conditions of this obliteration with which it 
is of considerable importance for us to be acquainted. 
The first is, that the clot contained in the interior of the vein 
should be completely removed from the contact of the air, that the 
exterior inflammation of the vein should be elevated to a moderate in- 
tensity, and that the animal should be in other respects in good health. 
xliv. 44 
