"No," said Thorndyke, "there was no report; it must have been a catapult."
The caretaker set the lamp down on the floor and proceeded to grope about for the projectile, in which operation we both assisted; and I could not suppress a faint smile as I noted the earnestness with which Thorndyke peered about the floor in search of the missile that was quietly reposing in his waistcoat pocket.
We were deep in our investigations when there was heard an uncompromising double knock at the street door, followed by the loud pealing of a bell in the basement.
"Bobby, I suppose," growled the caretaker. "Here's a blooming fuss about nothing." He caught up the lamp and went out, leaving us in the dark.
"I picked it up, you know," said Thorndyke, when we were alone.
"I saw you," I answered.
"Good; I applaud your discretion," he rejoined. The caretaker's supposition was correct. When he returned, he was accompanied by a burly constable, who saluted us with a cheerful smile and glanced facetiously round the empty room.
"Our boys," said he, nodding towards the broken window; "they're playful lads, that they are. You were passing when it happened, sir, I hear."
"Yes," answered Thorndyke; and he gave the constable a brief account of the occurrence, which the latter listened to, notebook in hand.
"Well," said he when the narrative was concluded, "if those hooligan boys are going to take to catapults they'll make things lively all round."