Every day and hour the man who deals with syphilis in accordance with
the best modern practice brings to bear knowledge that arises from our
knowledge of the germ cause of syphilis. No single fact except perhaps
the knowledge that certain animals (monkeys and rabbits especially)
could be infected with it has been of such immense practical utility in
developing our power to deal with it.

The germ of syphilis,[3] discovered by Schaudinn and Hoffmann in 1905,
is an extremely minute spiral or corkscrew-shaped filament, visible
under only the highest powers of the microscope, which increase the area
of the object looked at hundreds of thousands of times, and sometimes
more than a million of times. Even under such intense magnifications, it
can be seen only with great difficulty, since it is colorless in life,
and it is hard to color or stain it with dyes. Its spiral form and faint
staining have led to its being called the _Spirochæta pallida_.[4] It is
best seen by the use of a special device, called a dark-field
illuminator, which shows the germ, like a floating particle in a
sunbeam, as a brilliant white spiral against a black background,
floating and moving in the secretions taken from the sore in which it is
found. Some means of showing the germ should be in the hands of every
physician, hospital, or dispensary which makes a claim to recognize and
treat syphilis.

[3] See frontispiece.

[4] Pronounced spi-ro-kee'-ta.

+Syphilis a Concealed Disease.+--Syphilis is not a grossly conspicuous
figure in our every-day life, as leprosy was in the life of the Middle
Ages, for example. To the casually minded, therefore, it is not at all