in the wall of the heart. We see at once the part that the leucocytes play in attacking micro-organisms, and of localizing their action. Look at the blood-vessel in the wall of the heart with its plug of micro-organism (staphylococci) in the centre of a clear space; here the leucocytes are not numerous, indeed they are very sparsely scattered, and appear to have been driven back by the organisms or their toxics. Then a little distance away from the toxin and toxin-forming organisms, the leucocytes are coming up in large numbers, forming a sort of protecting army, as it were. This is known as leucocytosis. In the small patent vessels around this commencing abscess numerous leucocytes, far in excess of the usual proportion, may be seen—the nearer the abscess, the more numerous they become. Thus the leucocytes make their way to what is to become the wall of the abscess, and form a layer around a mass of micro-organisms, localizing, or attempting to localize, such mass. So long as the leucocytes can make their way to this mass, and shut it off from the surrounding tissue, so long we shall have no extension of the abscess.
"Now, if you add something—alcohol in the case we are considering—which not only exerts a negative chemiotaxic action—i.e., which drives the leucocyte away—but which, as we have seen, also causes degeneration of nerve, muscle and epithelial cells, shall we not injure the infected patient both directly and indirectly by interfering with the return of the leucocytes driven away, by diminishing or altering the functional activity of these cells, and indirectly by interfering with the excretion of the poisons (owing, as we have seen, to a degenerated condition of the secretory epithelium)? Have we not, in fact, a cumulative action of two substances, either of which alone would do damage, but not in the same proportion as do the two when acting together.
"Now let us see what we may learn from a series of experiments carried out by Dr. Abbott, working in the Laboratory of