period.  There is still a good deal of uncertainty as to just what the distribution of the germs which takes place in the secondary period foreshadows in the way of prospects for trouble when we come to the tertiary period.  It may well be that the man who had many germs in his skin and a blazing eruption when he was in the second stage, may have all his trouble in the skin when he comes to the late stage.  It is the verdict of experience, however, that people who have never noticed their secondary eruption because it was so mild are more likely to be affected in the nervous system later on.  But this may be merely because the condition, being unrecognized, escapes treatment.  It is at least safe to say that those whose skins are the most affected early in the disease are the fortunate ones, because their recognition and treatment in the secondary stage help them to escape locomotor ataxia and softening of the brain.  Conversely the victim who judges the extent and severity of his syphilis by the presence or absence of a “breaking out” is just the one to think himself well for ten or twenty years because his skin is clean, and then to wake up some fine morning to find that he cannot keep his feet because his concealed syphilis is beginning to affect his nervous system.

+Nature of the Tissue Change in Late Syphilis—­Gummatous Infiltration.+—­The essential happening in late syphilis is that body tissue in which the germs are present is replaced by an abnormal tissue, not unlike a tumor growth.  The process is usually painless.  This material is shoddy, so to speak, and goes to pieces soon after it grows.  The shoddy tissue is called “gummatous infiltration,” and the tumor, if one is formed, is called a “gumma.”  The syphilitic process at the edge of the gumma shuts off the blood supply and the tissue dies, as a finger would if a tight band were wound around it, cutting off the blood supply.  Gumma can develop almost anywhere, and where it does, there is a loss of tissue that can be replaced only by a scar.  In this way gummas can eat holes in bone, or leave ulcerating sores in the skin where the gumma formed and died, or take the roof out of a mouth, or weaken the wall of a blood-vessel so that it bulges and bursts.  The sunken noses and roofless mouths are usually syphilitic—­yet if they are recognized in time and put under treatment, all these horrible things yield as by magic.  There are few greater satisfactions open to the physician than to see a tertiary sore which has refused to heal for months or years disappear under the influence of mercury and iodids within a few weeks.  Still better, if treatment had been begun early in the disease, and efficiently and completely carried out, none of these conditions need ever have been.