"They couldn't find any evidence that the fish plate was put in the switch purposely. It might have dropped there. Of course some tramp might have put it there to get revenge for being put off a train, but it would be hard to prove. And as for getting evidence against Sim Dobley—why, it's out of the question. But you want to keep on looking out for yourself."
"I will," Joe promised.
After thinking the matter over Joe had decided it would be best to speak to the ring-master about the threatening letter, which had been received so close to the time when the derailment occurred. Jim Tracy had at once agreed with Joe that the discharged acrobat might possibly have been mad and rash enough to try to wreck the train, and the railroad detectives had been communicated with. But nothing had come of the investigation, and the accident had been set down as one of the many unexplained happenings that occur on railroads.
A search had been made for Dobley, but he seemed to have disappeared for the time being, and Joe was glad of it.
"Ready for the new stunt?" asked Tracy, as he passed on.
"Yes; I'll pull it off to-night if nothing happens," Joe said.
He was glad there were few people in the big tent when he entered it after the afternoon performance, to put in some hard practice. Joe's own trapeze was in place, but he lowered it to the ground, and went carefully over every inch of the ropes, canvas straps, snaps, and the various fastenings to make sure nothing was wrong. He found everything all right.
It was not exactly that he was suspicious of the Lascalla Brothers, but he was taking no chances.
Joe's act worked well in practice. When he had performed his trick for the last time he saw Benny Turton, the "human fish," coming into the tent to look after his tank, about which the young performer was very particular.
"How do you like that, Ben?" asked Joe, as he finished the new trick.