"Not one," said Beale, with a baffled little laugh, "didn't I tell you he's mighty clever? I got track of two of them but they were the only two where the sale didn't go through."
"What does he want houses for?"
"We shall learn one of these days," said Beale cryptically. "I can tell you something else, gentlemen, 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.