"Fenson," said Beale, "watch these flats. If you see a car drive up just go along and stand in front of the door. Don't let anybody enter that car or carry any bundle into that car until you are sure that Miss Cresswell is not one of the party or the bundle. If necessary you can pull a gun--I know it isn't done in law-abiding London," he smiled at Superintendent McNorton, "but I guess you've got to let me do a little law-breaking." "Go all the way," said the superintendent easily. "That will do, Fenson. You know Miss Cresswell?" "Sure, sir," said the man, and melted back into the shadows. "Where are you going now?" asked Kitson. "I am going to interview a gentleman who will probably give me a great deal of information about van Heerden's other residences." "Has he many?" asked Kitson, in surprise. Beale nodded. "He has been hiring buildings and houses for the past three months," he said quietly, "and he has been so clever that I will defy you to trace one of them. All his hiring has been done through various lawyers he has employed, and they are all taken in fictitious names." "Do you know any of them?" "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.