His cry attracted considerable attention, and a crowd was soon following our heroes, for it does not take even such an exciting cry as “Stop thief!” to collect a throng in busy New York.

“Stop those fellows! Stop ’em!” yelled Ned.

“They’ve got our money!” added Frank.

By this time the thieves were aware of the commotion behind them. They had evidently anticipated pursuit, for at the sound of their victims’ cries, and at the sight of the crowd that had gathered to help in the chase, the two men separated.

Where one went Frank and Ned could not see, as a pillar of the elevated structure hid him from sight. But the other ran up the stairway, and Frank noticed, with despair, that a train was just pulling into the station.

“He’ll get away on that,” thought Frank, “and the other will be lost in the crowd.”

And that was exactly what happened. When Frank and Ned, somewhat out of breath, reached the elevated structure neither of the men was in sight. But a policeman, attracted by the throng and the sight of the two excited boys, ran over from where he was standing in front of a steam-ship ticket office.

“What’s up?” he demanded, sharply.

“Pickpockets,” explained Frank briefly. “Two of ’em—they robbed my brother of his watch, and took my pocketbook—”

“Any money in it?” snapped out the policeman, while the crowd pressed around to hear what was going on.