Tom had a feeling that some desperate work was in prospect. The attack on him, the rendering of him unconscious, his being chained fast—all this was more than accidental coincidence following his trailing of the man who had disappeared down in the tunnel. For a moment those in the second boat remained gazing, spellbound, it seemed, at Tom, who was rapidly putting distance between himself and those he felt were his enemies. The boat he had so unexpectedly found proved to be a speedy little craft. But the other was also. “There’s Tom Swift now!” cried Schlump, pointing. “Where?” asked one of the masked men. “In our boat!” Schlump answered. “Come back here!” he roared, shaking his fist at Tom. “Come back nothing!” taunted the young inventor. “Don’t stop to talk!” shouted one of the masked men. “Speed up! We must catch Swift at any cost!” CHAPTER IV A NIGHT OF WORRY About nine o’clock on the night when Tom Swift had witnessed the strange actions of the man who so mysteriously disappeared, the telephone bell tinkled in the Swift home. As Tom’s father was reading a scientific book in which he was much engrossed, Mrs. Baggert went to the instrument. Half-interested in the conversation, Mr. Swift listened to the one-sided talk, hearing Mrs. Baggert say: “Oh, how do you do, Miss Nestor? No, Tom isn’t here. I haven’t seen him since supper. His father is here. Do you want to speak to him? What’s that? Oh, all right. Yes, I’ll be sure to tell him.” “Isn’t Tom over at Mary’s house?” asked the aged inventor, with a shade of anxiety in his voice as he looked up from his book. He had guessed at what he had not heard. “No, he isn’t there, and Miss Nestor is getting tired of waiting, I guess,” answered the housekeeper. “Where is Tom?” asked his father. “I don’t know,” Mrs. Baggert replied. “He started for Shopton right after supper, saying he had to buy some things at the hardware store before it closed. I heard Mr. Ned tell him not to be late and Tom promised he wouldn’t. I didn’t know then what Mr. Ned warned him not to be late for, but I can guess now that it was in calling on Miss Nestor.” “And he hasn’t arrived there yet,” murmured Mr. Swift. “That’s a bit odd, for Tom doesn’t usually break his engagements—especially with Mary Nestor,” and he smiled a little. “Oh, Miss Nestor told me to say to you that she wasn’t in the least worried,” Mrs. Baggert made haste to add. “She says she knows Tom is very busy and something may have come up at the last moment. She says he promised to take her to see a moving picture this evening. She has been waiting some time, and she called up to say if he couldn’t come it would be all right, and she would go to the second show with her mother. That’s all the message was about.”