"Didn't 'urt you, did it?" stormed the labourer aggressively. "'Course I look where I'm going." Then in a lower tone: "I'm Foyle. I got your telephone message. Anything moving now?"

"If you don't go away I shall call a constable." Green had been quick to see his cue and spoke loudly. He went on rapidly. "He hasn't stirred out. A post-office messenger has just gone in with a letter for him. I said I was expecting one, and got a glimpse at it."

"All right, old pal. Don't get excited. You go home and tell the missus all about it," retorted the labourer.

Green walked rapidly away, spoke a few words to a man who was standing on the other side of the road, deeply interested in a bookseller's window, and departed.

The superintendent felt in his pockets and produced a couple of boxes of matches. A constable strolled up, dignified and stern. A swift word in an undertone sent him away with burning cheeks.

In half an hour Foyle had sold a box of matches, for which he received sixpence with profuse thanks and inward disgust. If he sold his second box and still hung about, his loitering without excuse might attract undesirable attention. The contingency, however, did not arise, for a minute or two later Fairfield himself strolled into the street. Foyle rushed to open the door of a taxicab, which he hailed, but another tout was before him. Nevertheless, he heard the address.

"Grave Street, Whitechapel," he murmured to himself, as the cab slipped away. "Ivan has got to work."

A short argument with a second cab-driver, who dis

trusted his appearance, was cut short by a deposit of five shillings as a guarantee of good faith, and the superintendent also began the journey. Behind him a third cab carried the man who had been so deeply interested in the bookseller's window.