"But if anything should startle the horse or frighten him, anything unexpectedly, I mean, he would be in some danger of being thrown off, wouldn't he?" "That's so!" said Carden, as if a sudden idea had dawned upon his mind. "It seems a dangerous business, this," said the stranger, carelessly. "If, now, some malicious person should throw something at the horse when he was in the ring, it might prove dangerous to the boy." "So it would!" said Carden, eagerly. "Well, my friend," said the stranger, rising, "I see we've drained the bottle. Suppose we go out again." When they emerged into the street, Fitzgerald, for it was he, shook hands with the canvas man, and said: "Well, I must go back to the hotel. I hope to meet you again, my friend." "I think I've set things in train," thought Fitzgerald. "I will attend the circus this evening." CHAPTER XVII. AN ATHLETIC CONTEST. The two boy riders were taking their usual afternoon walk, when they met Carden. The canvas man frowned, but his face seemed also to wear an expression of triumphant malice, as if he could foresee some evil in store for Robert. "Did you notice how Carden looked, Robert?" asked Charlie. "Not very pleasant. He hasn't forgotten me for detecting him in his attempt to rob me." "He looked as if he had heard of some bad luck for you." "That must be your imagination, Charlie. I've had no bad luck." "I wonder what makes Carden stay here now he is discharged from the circus," said Charlie, thoughtfully. "I suppose he can stay here as cheap as anywhere," said Robert. "I don't trouble myself about him or his plans." "He is your enemy, Rob. He may try to do you some harm." "I will be on my guard, but I won't worry myself about it." They came to an open field, where half a dozen boys were engaged in athletic sports. There was soon to be a picnic, and prizes had been offered for the best running, leaping and vaulting, and these boys were engaged in practising for the grand contest. "Let us stop and look at them," said Charlie. "Very well," answered his friend. So they took up a position about fifty feet away and regarded the contestants with interest. Their presence was noticed by the boys, who at once recognized them as circus riders. "Let us invite them to join us," said Frank Perry, a boy of sixteen. "Yes," chimed in several others. "I object," said Ronald Percy, stiffly. "My father wouldn't care to have me associate with circus performers."