Now, this is quite a series of processes, all contributing to one result, and it is presided over, or directed, by the _vis medicatrix naturæ_. The object of this series is a definite one; and each process does its part in effecting it, and does it commonly at the right time, and in the right manner. Just look for a moment at the complicated character of this apparently simple operation. Here is quite a large deposition of substance which is to be removed; and this is the object to be effected. Observe how it is done. The softening of the swelling is not a mere change of solid substance into a fluid, as if by decay, but it is the result of an active process, which we call _suppuration_. When this process is properly performed, good pus is made, or as the old writers in medicine rather quaintly expressed it, _laudable_ pus. This process of suppuration, when it is well done, does not go on here and there in the swelling, making it like a honeycomb with a multitude of little abscesses; but there is a consent, an agreement of action by the vessels of the part, as really as if they worked intelligently. It is this consent of action which not only makes the line of movement in the abscess, but points it towards the surface, instead of giving it some other direction, laterally, or inward, upon some of the internal organs. But it is farther to be observed, that in this agreement of action, the vessels of the part do not all do one thing. Three different offices are performed by them in the different quarters of the abcess. While some of these little workmen are forming the pus, there are others thinning the wall of the abcess in the direction of the surface, by absorbing or taking up the substance there; while there are others still, in the rear, and at the sides of the abcess, depositing substance, in order to make a barrier to prevent the pus from being diffused in the surrounding parts. Each class of these workmen perform their particular work with even more exactness and harmony than would be expected of any company of intelligent laborers under the direction of a leader. The absorbents absorb together, the wall builders build together, and the makers of pus make pus together, and deposit it in a common reservoir. But observe farther, and you will soon see an entire change come over the whole scene of operations. When the absorbents have completed their passage for the matter through the skin, the pus is gradually discharged from its reservoir, and the “occupation” of the pus makers is soon “gone.” The wall builders also cease their work, and while the vacancy becomes filled up by contraction and deposition, the wall of defense, so carefully maintained, so long as it was needed, is now taken up by the absorbents—workmen which seem to know just when, as well as how, to do their duty, and is emptied into the common circulation, to be discharged from thence with the general refuse, by the various outlets of the system.