WEST OF ENGLAND VETERINARY MEDICAL ASSOCIATION. 55 
the horse on a thick bed of straw, to give the poor animal relief, by 
taking off the pressure from his feet in standing. He soon found 
that theory to be a delusion, for the hoofs began to slough, not¬ 
withstanding poulticing, &c. &c., and the horse was obliged to be 
destroyed. 
Before entering upon the pathology of the disease under con¬ 
sideration, it may not be out of place to give a short svnopsis of 
inflammation. 
HypercBmia .—The arrangement occurring best to my mind to give 
a general idea of inflammation is as follows ; 
1st. Hypersemia with a diminished motion of blood in the part. 
2nd. Hyperaemia with increased motion of blood in the part. 
3rd. Hypersemia with motion partly increased and partly dimin¬ 
ished. 
The 1st of these states we will call Congestion ; the 2nd, Deter¬ 
mination of blood; the 3rd, Inflammation. 
The two principal causes producing congestion are—1st, obstruc¬ 
tion of various kinds to the return of blood through the veins, me¬ 
chanical or otherwise ; the 2nd, a relaxed and toneless state of the 
capillaries and small veins, and this may be produced either by 
local passive plethora^ as seen in a varicose vein, or atony occurring 
secondarily in consequence of previous inflammation. 
I am under the impression that the 1st state (that of hypermmia), 
with diminished motion of blood in vessels, is the all-important one 
to explain the rationale of laminitis. Yet I wish to point out that 
local hypercemia^ which we purpose laying much stress on in 
laminitis, differs somewhat from local plethora. Local hyper^emia 
also differs from general hypersemia or plethora. Local hypersemia 
is not exactly local plethora; it simply implies that too much blood 
is accumulated in the vessels of the part, without in any way in¬ 
fluencing the general nature of the blood throughout the system. 
Congestion plays an important part in inducing pathological 
changes ; it occasions serious structural alterations, and runs into 
inflammation. Congestion is always a passive and mechanical con¬ 
dition, hence the term active congestion should not be employed. 
Indeed, what has been described as ‘‘active congestion ” is in reality 
a variety of the inflammatory process. Congestion is a true 
hypersemia; in it we find, not only that the blood is greatly increased 
in quantity, but that it circulates languidly through the part, and is 
of a darker colour than natural. The arteries are, at most, of their 
normal size, perhaps even contracted ; the veins and capillaries are 
greatly distended by the slowly moving fluid. When the circulation 
in the congested part becomes completely arrested stagnation is 
said to have occurred. 
Determination .—Increased vascular action lies at the bottom of 
most reparative processes, few important actions taking place 
without it. No process by which the separation of dead parts 
is effected, or by which the repair of wounds or ulcers is carried 
out, can occur without an increased activity of the vessels of the 
parts concerned. Every tissue is susceptible of it, and the veterinary 
