“I’m afraid so,” admitted Joe ruefully.  “I wouldn’t be a bit surprised but what this was some of the work of Bill Carfax.”

“Has he been around again?” asked Helen, and there was a note of annoyance in her voice.

“He hasn’t been seen,” said Joe.  “But this man may have been in communication with him.  Bill may have been studying the trick out since his last failure, and I must admit that he’s on the right trail—­that is, if it was Bill who put this man up to making the claim.”

“What makes you think Bill had anything to do with it?” asked Helen.

“Well, for the reason that this is just the kind of town where Bill would be likely to have friends—­I mean in a big manufacturing center.  Bill may have found a man who is willing to act to help pull down the reward for him.  But this time they failed.”

“He may succeed next time,” remarked Helen.

“No, I’ll take care of that,” Joe said.  “I’m going to make a change in the box.”

As the mechanism of the trick box has been explained in the preceding volume, it will not be repeated here.  Suffice it to say that Joe’s method of getting out of the box could be changed, so that if a person thought he had discovered the secret panel it could be shifted to another part of the case.

It was two or three days after this, and Joe had made a change in his box which satisfied him that the secret would not soon be discovered, that Helen, coming over to where he sat in his private tent, saw him making what seemed to be torches.

“What are you doing?” she asked.  “Do you think our electric lights or gasoline flares are going to fail?” she went on jokingly.  The Sampson Brothers’ Show was a modern one, and carried a portable electric light plant.

“Oh, no, I’m not worrying about that!” answered Joe.  “But I have a new idea for my wire act, and I want to see if it will work out.”

That night, at the proper time, when Joe was introduced as about to perform his wire act, Helen noticed Ham Logan come out with the young fire-eater, carrying a number of the torches Joe had made.

Joe started across the high, slack wire, and on it performed many of his usual feats.  They were not specially sensational, and Helen wondered what he had planned.

But, after a daring run across the slender support, following some risky side swinging, Helen saw Joe lower from the high platform where he stood a flexible wire.  Standing on the ground below, Ham Logan received it and fastened on the end several of the metal torches Joe had made.  The young magician hauled them up to him by means of the wire.

Then, as Helen and the audience watched, Joe set the torches ablaze.  They were made of hollow cones of sheet iron, in which were placed bits of tow, soaked in alcohol.

With four blazing torches, two in either hand, Joe Strong started out to cross the high, slack wire.  And then, to the wonder and amazement of the audience, no less than that of his friends in the show, Joe began juggling with fire.