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the theory of Inflammation. It being sufficiently obvious, that inflammation is 
strictly a vital process, and one in which the flow of blood through the affected 
part is materially changed, it was naturally supposed that the vital powers by 
which that movement is affected in the natural state, must be those which undergo 
modification in this diseased state; when, therefore, it was believed that the only 
truly vital power concerned in the organic functions of the living body is one form 
or other of contractility, the only explanations of the phenomena of inflammation 
that were attempted turned on the possible modifications of the contractile powers 
of vessels, as influenced by their contents or through their nerves. But I believe it 
is now pretty generally admitted, that all this was nearly lost labour; and if phy- 
siologists had earlier seen that the most fundamental and characteristic of all 
strictly vital actions,—those by which nutrition and secretion are effected, and 
which have always more or less of a chemical character, take place, not in vessels, 
but in cells, independently of any contractions of the organs containing the fluids 
—that they are most obvious in those living beings which have neither heart, 
arteries, nor veins ;—and that, as occurring in the higher animals, they are carried 
on partly in the interior of the fluids contained in the vessels, and partly in the 
matter that has exuded from the vessels and lies exterior to them,—they would 
sooner have perceived, that all the changes of action of the organs of circulation, 
heart, arteries, or capillaries, in the case of inflammation, are to be regarded as 
effects of the truly essential, fundamental, and strictly vital changes, which take 
place im the fluids of an inflamed part, and in the relation between the fluids and 
solids there; i.¢., in matter which is apparently at rest, and much of which, 
being outside the vessels of the part, has escaped from all influence of the vital 
contractions either of heart or vessels. 
I do not say that we have a satisfactory explanation of inflammation merely by 
taking this view of it,—regarding it as fundamentally a perversion of nutrition or 
secretion, and the circulation as only secondarily affected; but I maintain that 
in this way we can understand, and so far explain, by reference to more general 
facts, known in the history of the sound as well as the diseased body, many facts 
as to it, which we never understand at all so long as we think only of altered 
action of vessels,—but which are easily arranged along with others previously known, 
when we regard them only as indications of changes in vital actions that are con- 
stantly going on in living fluids, both those contained in vessels, and those recently 
_ delivered from them, into the cellular structure of living parts. Thus, we can 
perceive how inflammation should spread, as it does, not along the course of vessels, 
but from a point as from a centre,—not only along continuous surfaces, but to con- 
tiguous surfaces lying beside them, but supplied from other vessels, the larger 
branches of which frequently undergo little or no change in the process ; thus we 
can perceive how the amount of effusions and exudations from the blood in in- 
flamed parts should bear no fixed proportion to any action of the heart, or of 
