The treasurer was called in consultation with Joe and Tracy and other circus officials, and it was decided to keep a special watch on the ticket wagon and the ticket takers that night.

Joe quickly made the change in his trapeze and tested it, finding that he could work it perfectly.  Then he began to think of his new fire-eating act.  He was determined to make that as great a success as was his now well advertised ten thousand dollar mystery box act.

The evening performance had not long been under way, and Joe had done his big swing successfully, when he was sought out by Mr. Moyne.

“The same thing has happened again,” said the treasurer.

“You mean more people coming in than we have sold tickets for?”

“That’s it.”

“Well, where do the extra admissions come from?  I mean where do the people get their admission slips from—­the extra people?”

“That’s what we can’t find out,” the treasurer aid.  “As far as the ticket takers can tell only one kind of admission slip for the fifty cent seats is being handed them.  But the number, as tallied by the automatic gates, does not jibe with the number of ordinary admissions sold at the ticket office.  To-night there is a difference of about eight hundred and seventy-five.”

“Do you mean,” asked Joe, “that that number of persons came in on tickets that were never sold at the ticket wagon?”

“That’s just what I mean.  There is an extra source from which the ordinary admission tickets come.  As I told you this afternoon, we are having no trouble with our reserved seats.  There have been no duplicates there.  But there is a duplication in the fifty cent seats, where one may take his pick as to where he wants to sit.”

“Don’t we have tickets on sale in some of the downtown stores?” Joe asked.

“Oh, yes, several of the stores sell tickets up to a certain hour.  Then they send the balance up here for us to dispose of.”

“How about their accounts?  Have you had them gone over carefully?”

“They tally to a penny.”

“How about the unsold tickets these agents send back to us?  Isn’t there a chance on the way up for some one to slip out some of the pasteboards, Mr. Moyne?”

“There is a chance, yes, but it hasn’t been done.  I have checked up the accounts of the stores, and there is the cash or the unsold tickets to balance every time.  But somehow, and from some place, an extra number of the ordinary admission tickets are being sold, and we are not getting the money for them.”

“It is queer,” said Joe.  “I have an idea that I want to try out the first chance I get.  Save me a bunch of these ordinary admission tickets.  Take them from the boxes at random and let me have them.”

“I will,” promised the treasurer.  “There is nothing we can do to-night to stop the fraud, is there?” he asked.  Mr. Moyne was a very conscientious treasurer.  It disturbed him greatly to see the circus lose money.