"Jack Diamond-am I dreaming?" Frank Merriwell uttered the exclamation. He was in front of the Hoffman House, in New York. Three young men in evening dress had just left the hotel, and were about to enter a cab that had drawn up to the curb for them. Frank stared in astonishment at one of them. He was a slender, clean-cut, handsome fellow. "Jack Diamond " he repeated; "can it be? Why, I supposed he was in London " One of the men, his silk hat thrust...