emen, and this is more of a suspicion than a
certainty, that there is not a crank scientist who has ever gone under
through drink or crime in the whole of this country, aye, and America
and France, too, that isn't working for him. And now, gentlemen, if you
will excuse me----"

"You don't want any assistance?" asked the superintendent.

"I guess not," said Beale, with a smile, "I guess I can manage the Herr
Professor."

* * * * *

On the south side of the River Thames is a congested and thickly
populated area lying between the Waterloo and the Blackfriars Roads.
Here old houses, which are gauntly picturesque because of their age,
stand cheek-by-jowl with great blocks of model dwellings, which make up
in utility all that they lack in beauty. Such dwelling-places have a
double advantage. Their rent is low and they are close to the centre of
London. Few of the houses are occupied by one family, and indeed it is
the exception that one family rents in its entirety so much as a floor.

In a basement room in one of those houses sat two men as unlike one
another as it is possible to conceive. The room itself was strangely
tidy and bare of anything but the necessary furniture. A camp bed was
under the window in such a position as to give its occupant a view of
the ankles of those people who trod the pavement of the little street.

A faded cretonne curtain hid an inner and probably a smaller room where
the elder of the men slept. They sat on either side of a table, a
kerosene lamp placed exactly in the centre supplying light for their
various occupations.

The elder of the two was bent forward over a microscope, his big hands
adjusting the focus screw. Presently he would break off his work of
observation and jot down a few notes in crabbed German characters. His
big head, his squat body, his long ungainly arms, his pale face with its
little wisp of beard, would have been recognized by Oliva Cresswell, for
this was Professor Heyler--"the Herr Professor," as Beale called him.

The man sitting opposite was cast in a different mould. He was tall,
spare, almost aesthetic. The clean-shaven face, the well-moulded nose and
chin hinted at a refinement which his shabby threadbare suit and his
collarless shirt freakishly accentuated. Now and again he would raise
his deep-set eyes from the book he was reading, survey the absorbed
professor with a speculative glance and then return to his reading.

The