They turned down Girard Avenue. The car was half a block in advance of them. “You're energetic enough in this pursuit,” Amy shouted back to the doctor as the machine fled over the stones, “even if you don't believe in it.” “Energetic in your service, now and always.” She made no answer. This time her reflections were abruptly checked--as his had been on Broad Street--by the cry of the other. “See! He's getting off at the Girard Avenue Theatre.” Again they found a custodian for their bicycle and followed Appleton into a theatre. The young man stopped at the box-office in the long vestibule, bought a ticket, and had a call made for a coupé. Then he passed through the luxurious little foyer, beautiful with flowers and soft colours, and stood behind the parquet circle railing. Adelaide Randall's embodiment of “The Grand Duchess” held his attention for a time. Haslam and Miss Winnett, to avoid the risk of being discovered by him, sought the seclusion of the balcony stairs. “We had a few bars of Offenbach at the Park, and here we have Offenbach again,” commented the doctor. “And again, only a few bars, for there goes our man.” Appleton, having given as much attention to the few spectators as to the players, left the theatre and got into the cab that had been ordered for him. Haslam, behind the pillar at the entrance to the theatre, overheard Appleton's direction to the driver. It was: “To the Grand Opera House. Hurry! The opera will soon be over.” The cab rumbled away. “It's well we heard his order,” observed Haslam to Amy. “We couldn't have hoped to keep up with a cab. He'll probably wait at the Grand Opera House till we get there.” “But we mustn't lose any time, for, as he said, the performance will soon be over.” “Oh, 'Tell' is a long opera and Guille will have an encore for the aria in the last act. That will give us a few minutes more.” III _A Telegraphic Revelation_ A boy walking down Girard Avenue, as Appleton got into the cab, had been whistling the tune of “They're After Me,”--a thing that was new to the variety stage last fall, but is dead this summer. The air, whistled by the boy, clung to Appleton's sense, and he unconsciously hummed it to himself as his cab went on its grinding way over the stones. The cabman was considerate of his horse, and he coolly ignored Appleton's occasional shouts of, “Get along there, won't you?” It was, therefore, not impossible for the bicyclists to keep in sight of the coupé. “All this concern about a man you say you don't care for,” said Haslam to Amy, as the bicycle turned up Broad Street. “It's unprecedented.” “It's only humanity.” “You didn't bother about following me around like this when you threw me over.” “You didn't threaten to kill yourself.” “No; if I had, I'd have carried out my threat. But for months I endured a living death--or worse.” “Really? Did you, though?” Eager inquiry and sudden elation were expressed in this speech.