DUKING THK SCHOLASTIC YKAR 1838-9. 
183 
perfectly adherent above, or if the membranes have been cut by a 
ligature"too tightly drawn, or, finally, if with a view to a practical 
experiment an opening has been made in the vessel above the liga¬ 
ture—in all these conditions, the air establishing itself in contact 
with the blood, the concentric layers of the clot begin to be effaced. 
The clot itself becomes altered—it liquefies, and escapes through the 
opening in the vessel in the form of a deliquum, which diffuses a 
noisome gangrenous odour. The canal of the vein being re-esta¬ 
blished in consequence of the termination of the adherence of the 
clot, haemorrhage immediately succeeds, and the result is ine¬ 
vitable. 
If the exterior inflammation is elevated to too acute a type, the 
incubation—if we may use the term—of the clot within the ves¬ 
sel can no longer proceed. It becomes suppurated, and an abscess, 
formed by the softened fibrine and by the pus that is mingled with 
it, is developed in the very interior of the vein. 
That, however, which may render this accident less serious, is 
that often, above the place where the too intense inflammation has 
determined the suppuration of the clot, its type is sufficiently mo¬ 
derate for it to become adhesive. Then the clot becomes organized, 
and no haemorrhage takes place. 
Finally, when the blood, by reason of the bad constitution of the 
animal, is not in a healthy state, the organization of the clot is slow 
in its formation—the ligature falls before the adhesion is perfect 
—contact with the air is established—and all the phenomena just 
described take place. 
Let any one compare these phenomena of which the jugular vein 
is the seat in consequence of a ligature, with those which exhibit 
themselves in the same vessel when thrombus has determined in¬ 
flammation there, and he will be struck with their perfect identity. 
Thrombus develops itself in a healthy animal, determines by its 
presence a degree of pressure on the jugular, and effects the obli¬ 
teration of it; a clot forms itself in the interior of the vessel—the 
external membranes become inflamed—the organization of the clot 
is effected—and the vein is obliterated. This is the process of ad¬ 
hesive inflammation. 
At other times, at the period when the clot is undergoing the 
process of organization, the animal rubs his neck—he determines 
a dilatation of the vein at the place where the puncture for bleed¬ 
ing was made—the adhesion of the interior clot is broken—the air 
establishes itself in contact with it, and effects the softening of it; 
and then consecutive haemorrhages manifest themselves, more abun¬ 
dant and more fearful, in proportion to the largeness of the opening. 
At other times, whether it is because the animal has rubbed him¬ 
self at a period more distant from the commencement of inflainrna- 
