“Oh!” murmured Helen, as she watched.  “It was only another of his sensational acts.  When I first saw the blazing hoops I half thought that some one was trying to injure Joe, as they did when the acid was used on his high trapeze.  Oh, it was only a trick!”

And so it was.  Joe had planned it that day after meeting Ham Logan.  The latter, talking about the time when he, too, had been a fire-eater, had mentioned an act where a performer leaped through blazing hoops, and Joe determined to use the idea, varying it to suit his purpose.  That it was effective was evidenced by the long-continued applause.

“But, Joe,” asked Helen, when the performance was over and she and Joe had received another ovation at the conclusion of the box mystery and the vanishing lady trick, “wasn’t there danger of setting your clothes on fire when you went through the blazing hoops?”

“None at all,” Joe assured her.  “I have been planning a stunt like this for some time, and my garments were fire-proofed.  Of course I wouldn’t have done it otherwise.  Look here!”

He took up a fancy jacket he had worn in his wire slide.  Taking a match Joe lighted it and held it against the cloth.  It did not take fire.

“There was that day—­”

“But I have perfected the act since then, Helen.  Of course the tungstate of soda that I soaked the clothes in wouldn’t keep them from catching fire if I put the suit in a furnace.  But the solution will make cloth resist a blaze temporarily, as will alum under some circumstances.  I use alum on the suit I wear when I pretend to set myself on fire and then jump into the tank of water,” went on Joe.  “But after this I’m going to use the soda.  It’s more certain.”

Joe worked the trick of seeming to set himself ablaze in this way.  As he said, his suit was made as nearly fireproof as possible.  Then on the back of his jacket were placed some bunches of tow saturated with alcohol.  When this tow was set on fire it burned quickly, but Joe knew the flame would not last long.  And the fact that the garments on which the burning material was fastened were as nearly fireproof as was possible to make them gave him additional safety.  He really ran little risk, as the fire was at his back, and, as he ran toward the tank, his speed carried the flames away from him.

Joe, and all others who do a fire-eating act, calculate to a nicety just how long a certain fire will burn.  And they do not place the blazing material into the mouth until the flames are almost on the point of going out of themselves.  This, added to the fact that a chemical solution protects the tongue and lips, makes the act comparatively safe.  But one word of caution. Do not try to fire-proof the mouth with tungstate of soda.  This warning cannot be made too strong!

In fact, it is well not to try any fire-eating at all.  It is too risky unless one is a professional.

“Well, Joe,” remarked Jim Tracy, later that night when most of the circus folk were asleep, “if you want to add this fellow to our show, go ahead.  You have the say, you know.”