syphilitics treated with it have been deceived by this notion into
believing themselves cured. In those whose symptoms came back in severe
form, the trouble was, of course, found out. But there are at the
present time, undoubtedly, many persons who received a single dose of
salvarsan for a syphilis contracted at this time, and who today, having
never seen any further outward signs of the disease, believe themselves
cured, when in reality they are not. In the next twenty years the
introduction of salvarsan will probably result in a wave of serious late
syphilis, the result of cases insufficiently treated in the early days
of its use. It was not long before it was found that not one but several
doses of salvarsan were necessary in the treatment of syphilis, and soon
many physicians of wide experience began to call in mercury again for
help when salvarsan proved insufficient for cure. At the present time
the use of both mercury and salvarsan in the treatment of the disease is
the most widely accepted practice, and seems to offer the greatest
assurance of cure.

+The Value of Salvarsan.+--Salvarsan has done for the treatment of
syphilis certain things of the most far-reaching importance from the
standpoint of the interests of society at large. It has first of all
made possible the control of the _contagious_ lesions of the disease.
Secondly, as was said before, it has made possible the cure of the
infection in the primary stage, before it has spread from the
starting-point in the chancre to the rest of the body. To understand how
it accomplishes these results it is important to understand its mode of
action.

+The Action of Salvarsan.+--It will be recalled that Ehrlich planned
salvarsan to kill the germs of syphilis, just as quinin kills the germs
of malaria. It was intended that when the drug entered the blood it
should be carried to every part of the body, and fastening itself on the
spirochetes, kill them without hurting the body. This is seemingly
exactly what the drug does, and it does it so well that within
twenty-four hours after a dose of it is given into the blood there is
not a living germ of syphilis, apparently, in any sore on the body. If
the same thing happened in all the out-of-the-way corners of the body,
the cure would be complete. The natural result of removing the cause of
the disease in this fashion is that the sores produced by it heal up.
They heal with a speed and completeness that is an even greate