"It seemed like a piece of string." "A piece of string. That may explain it. Hamilton, what do you know of this?" "Nothing, Captain Hayden. Grit was not with me. I left him in his kennel, in the stable, chained up." "We must look into this. Lieutenant Stiver, tell Sander to bring the bulldog here." "Perhaps I had better go along," suggested Dick. "Grit might make a fuss." "If he goes, you had better make sure he doesn't slip the string off the dog's tail," put in Dutton, with a sneer. Dick started, and looked angrily at his enemy. "That will do, Dutton," said Captain Hayden quietly. "You may accompany Sander, Hamilton." Toots, who was on hand, started for the stables, followed by Dick. "Are you going to get into trouble?" asked the old man, who had taken quite a fancy to our hero. "I hope not. If Grit had anything to do with firing the gun, by means of a string tied to his tail, some one who had a grudge against me is responsible for it." "I'm sure of it, Mr. Hamilton," and Toots marched on, whistling "Dixy Land," ending up with a series of bugle calls. They found Grit cowering in his kennel, as if much frightened. Dick and Toots looked him over. Sure enough there was a stout piece of cord tied to his stump of a tail. "It looks bad," commented Toots. "I'm not worried," declared Dick. Captain Hayden looked grave, when Toots handed him the bit of cord. He sent Sander to the saluting gun, and Toots returned presently with same cord, which matched that taken from Grit's tail. "Was this on the gun?" asked the head master. "Attached to a primer, that had been fired," replied Toots. "Hamilton," began Captain Hayden, "I don't like to accuse you on such circumstantial evidence, but it looks--" "I had nothing to do with firing the gun," said Dick quickly. "If my dog did it, some one else tied the string to his tail." "Whom do you suspect?" "I don't know." "If you please, sir," spoke up Graham, "I don't think Hamilton had anything to do with firing the gun." "Why not?" "Because my window is right opposite it. I was looking out, just before it went off, and I saw a crowd of students near it. They had a dog, for I could hear him growl, and I heard some one say 'look out or the brute will put his teeth in you.' Then some one else said, 'I guess I can manage him.' If Hamilton had been there I don't believe Grit would have growled." "He certainly would not," said Dick, noticing that Dutton was scowling at Graham. "Ha! Hum," mused the head master. "I believe you are right, Graham. Hamilton, you are practically exonerated, but this matter will not be allowed to drop. Firing the gun was a serious infraction of the rules, and dangerous in the bargain. Whoever fired it must have stolen into the ammunition house, which is a risky thing to do, especially in the dark." "I am glad you don't think I did it, sir," said Dick to Captain Hayden.