There was much wonder as to how the trick was it done, especially since the chair had been placed over a sheet of paper on the stage, and, before and after the trick, the professor had exhibited the sheet--the front page of a local paper--apparently unbroken. (This trick is explained in detail in the first volume of this series, entitled, "Joe Strong, the Boy Wizard.") "The audience seems to be in good humor to-night," observed the professor to Joe, as they bowed again. The two could carry on a low-voiced conversation while "taking" their applause. "Yes, I'm glad to see them that way," answered the youth. "It's not much fun playing to a frosty house." "I should say not! Well, Joe, get ready for your pigeon-omelet trick, and I'll prepare the fire apparatus." The professor, with a final bow, made an exit to one side of the stage, which was fitted up with Oriental splendor. As he went off, and as Joe Strong picked up some apparatus from a table near him, a disturbed look came over the face of the boy wizard. "I don't like that fire trick," he mused. "It's altogether too uncertain. It's spectacular, and all that, and when it works right it makes a big hit, but I don't like it. Well, I suppose he'll do it, anyhow--or try to. I'll be on the lookout though. If the current fails, as it did last time----" Joe shrugged his shoulders, and went on with his trick. Since he had become associated with Professor Rosello, Joe had adopted the philosophic frame of mind that characterizes many public performers, especially those who risk bodily injury in thrilling the public. That is, he was willing to take the chance of accident rather than disappoint an audience. "The show must go on," was the motto, no matter how the performer suffered. The public does not often realize its own cruelty in insisting on being amused or thrilled. "Yes, I'll have to keep my eyes open," thought Joe. "After all, though, maybe nothing will happen. And yet I have a feeling as if something would. It's foolish, I know,, but----" Again Joe shrugged his shoulders. There was nothing he could do to avoid it, as far as he could see. Joe was beginning to acquire the superstition shared by many theatrical persons. The theatre, filled with persons who had paid good prices to see Professor Rosello's performance was hushed and still now, as Joe, his preparations complete, advanced to the edge of the stage. He was smiling and confident, for he was about to perform a trick he had done many times, and always with success. For the time being he dismissed from his mind the risk Professor Rosello would run in doing the "fire trick," for which the chief performer was even then preparing. "Persons in the audience," began Joe, smilingly addressing the house, "often wonder how we actors and professional people eat. It is proverbial, you know, that actors are always hungry. Now I am going to show you that it is easier for us to get food than it is for other folk.