“Indeed, I’m not. Two or three times, while I was singing and dancing, I saw faces peering in at me. I thought you had some men checking up.” “No, indeed!” cried Tom. “Ned, I believe the spies are at work again!” This seemed very possible when the two compared notes. Though Koku on guard outside the laboratory had reported no suspicious persons around, this much could not be said of the room where Ned performed. “We’ll guard that, too!” decided Tom, and the next time when a “show” was put on, Eradicate was on duty to see that no one approached the windows. Who the unbidden spectators could have been Tom had no idea, but he guessed they were emissaries from the men seeking to discover his secret. As the days went on Tom Swift became more and more convinced that he was being closely watched by men who had a vital reason for discovering his secret. That these men were those interested in moving pictures and theatrical shows was certain. Tom realized what it would mean if their form of entertainment could be presented in even the humblest home in connection with the broadcasting of music, once his invention was successful. It was one night when Ned had been performing a long time and when the results were not as satisfactory as at first that Tom, sinking wearily back in his chair and wondering what was wrong, heard a commotion in the corridor outside his private laboratory. “No go in! No go in!” Koku’s big voice boomed. “Nonsense! Of course I’m going in!” another voice responded. “Bless my toothbrush, but I want to see Tom.” “Come on in, Mr. Damon!” called out the young inventor, as a new and daring idea came to him. “It’s all right, Koku,” he went on to the giant. “Let Mr. Damon in. Look here,” said Tom, addressing his eccentric friend, “can you sing and dance?” “Why—bless—well, I don’t know, Tom. I used to,” and Mr. Damon chuckled. “I once was given to taking part in amateur minstrels. But is this a joke or a serious question?” “It’s serious business. Just as you came along I happened to think that perhaps what I need at the visual sending end is a contrast of color. That might solve the problem, the difference in light rays—red at one end of the spectrum and violet at the other. It’s worth trying. But I need two performers. Ned’s in there now. He has on a violet suit—regular clown’s outfit. Will you put on a red one and help?” “I’ll do anything, Tom, but eat onions. I hate ’em! Never could touch the things. So outside of that I’m at your service. I just stopped in casually on my way home and——” “You’re just in time!” interrupted Tom. “This thing is giving me the dingbats, or it will if I don’t solve it soon. Come on, I’ll have to pass you in, for Eradicate is on guard.” Ned, who was resting after his singing and dancing, attired in a violet-colored suit, as Tom had said, welcomed Mr. Damon. Tom quickly explained his new plan, and when Koku and Eradicate had made sure no interlopers were around, the new experiments were begun.