ON INFLAMMATION. 
and the heart, and the orifice being of the same size in both, 
more than twice as much blood will be drawn from the in¬ 
flamed limb in the same time as from the sound one, shewing 
that twice as much blood has traversed the vessels of that limb. 
The turgescence of the veins likewise between the inflamed 
part and the heart will sufficiently indicate that a greater 
quantity of blood than usual is passing through the vessels. 
If more blood pass through the capillaries of the inflamed 
part, more must be supplied by the arteries; and therefore in the 
neighbourhood of the part they labour more to expedite the 
flow of blood; and the muscular coat in them also contracts 
more powerfully, and draws after it the elastic, and the elastic 
returns again to its former calibre, with a velocity and force equal 
to that of the contraction; and here too a vacuum is or would be 
more speedily formed, and to a greater extent, and more blood is 
solicited, or must flow on from the larger vessels beyond. On 
this account there is al ways increased throbbing of the arteries 
in the neighbourhood of tire inflammation. Not increased fre¬ 
quency of pulse (the pulsation is synchronous with the beat¬ 
ing of the heart), but altered character of the pulsation—increased 
fulness and hardness, proving that a greater quantity of blood 
is traversing the part. If the inflammation is circumscribed, or 
not intense, the increased quantity of blood permeating the 
vessels of the part is not great, and therefore the larger arteries, 
and at a distance from the inflamed part, are not perceptibly 
affected : but in more serious cases the labour exacted from the 
neighbouring vessels, to furnish the increased demand, is soon 
required from the yet larger vessels, and from the heart itself; 
and the heart begins to beat not only more forcibly, but more 
rapidly. The circulation through the whole of the frame is 
now affected, and symptomatic fever is the result. 
It may not be uninteresting to compare this simple definition 
of inflammation “increased action of the capillaries,*’ with the 
usual symptoms which indicate its presence. The first is red - 
ness , not indeed perceptible in every case of external inflamma¬ 
tion in the domestic quadrupeds, for their skin is thick, and that 
skin is covered with hair; but there are in them portions of the 
frame in which this character of inflammation may be clearly 
enough perceived, either during life, or by post mortem exami¬ 
nation. We judge of the violence of inflammation of the eye by 
the redness of the conjunctiva, and of the repiratory passages 
and organs by the redness of the continuous membrane of the 
nose. In the lungs, the stomach, and the intestines, w r e regard 
the injection of the vessels and the colour of the parts as 
indications of the nature and the intensity of the disease. 
