The cab now went on up Fifth Avenue, and at a slower pace than it had previously been going.

Thus Sixty-eighth Street was reached, and, when near the corner, the cab drew alongside the curbstone, the two occupants alighting and proceeding on foot.

Patsy was out in a moment. As the two disappeared around the corner, he ran at full speed; Chick, a little distance behind him, also following rapidly on foot.

When Patsy reached the corner the pair were nowhere to be seen. For the moment the young detective was at a loss to know what to do.

Thinking that if they had entered any one of the houses it must have been one very close to the avenue, and that, if so, they would have hardly had time to pass through the door, and were under the concealment of a vestibule, he ran down the street hastily in the hopes that he might discover them.

Just as Chick reached the corner, two figures leaped out at Patsy.

They were the pair he had been following.

The young man went at Patsy rather viciously, crying, as he did so:

“What are you following us for?”

Though the attack was unexpected, Patsy was not unprepared, and, squaring himself, warded off the blow the young man had aimed at him.