vior of a given germ may be due to differences among the
various strains or families of germs in the same general group. Another
part is due to the habit which germs have, of singling out for attack
the weakest spot in a person's body. The germ that causes rheumatism has
strains which produce simply tonsillitis, and others which, instead of
attacking joints, tend to attack the valves of the heart. Our recent
knowledge suggests that somewhat the same thing is at work in syphilis.
Certain strains of Spirochaeta pallida tend to thrive in the nervous
system, others perhaps in the skin. On the other hand, in certain
persons, for example, heavy drinkers, the nervous system is most open
to attack, in others the bones may be most affected, in still others,
the skin.

+Variations in the Course of Syphilis in Different Persons.+--So it
comes about that in the secondary stage there may be wide differences in
the amount and the location of the damage done by syphilis. One patient
may have a violent eruption, and very little else. Another will scarcely
show an outward sign of the disease and yet will be riddled by one
destructive internal change after another. In such a case the secondary
stage of the disease may pass with half a dozen red spots on the body
and no constitutional symptoms, and the patient go to pieces a few years
later with locomotor ataxia or general paralysis of the insane. On the
other hand, a patient may have a stormy time in the secondary period and
have abundant reason to realize he has syphilis, and under only moderate
treatment recover entirely. Still another will have a bad infection from
the start, and run a severe course in spite of good treatment, to end in
an early wreck. The last type is fortunately not common, but the first
type is entirely too abundant. It cannot be said too forcibly that in
the secondary as in the primary stage, syphilis may entirely escape the
notice of the infected person, and he may not realize what ails him
until years after it is too late to do anything for him. Here, as in the
primary stage, the lucky person is the one who shows his condition so
plainly that he cannot overlook it, and who has an opportunity to
realize the seriousness of his disease. It used to be an old rule not
to treat people who seemed careless and indifferent until their
secondary eruption appeared, in the hope that this flare-up would bring
them to their senses. The necessity for such a rule shows plainly h