"What do you suggest?" asked Andy, after a pause.

"I hardly know. Let's puzzle over it a bit." Again there fell a silence between them--a silence fraught with much meaning. They could hear revelry in other college rooms, and the call of lads on the campus. From farther off came the roar and hum of the city. It reminded Andy of the night he had first come to New Haven. How many things had happened in that time. He would soon be a soph.o.m.ore now--no more a callow freshman.

"Do you know," spoke Dunk, in a low voice, as he again changed his position, seeking ease. "I had an idea that Ikey might turn out to be the guilty one."

"So did I," admitted Andy. "That was after your watch was missing, and I found he had been in the room while I was out. But, for that matter, Link was in there, too. It was a sort of toss-up between the two. Poor Link, it's been mighty unpleasant for him, to be accused wrongly. I wonder how that valuable book got in his room?"

"The quadrangle thief put it there, of course."

"And there's that case of Pulter's book--found out near Yale Field,"

went on Andy. "I suppose Mortimer had that, too."

"Very likely, though it seems queer that he'd stoop so low as to take books."

"He could p.a.w.n 'em, I suppose, same as he did the other things he took,"

Andy continued.

"The way he used to borrow money from me and some of the other fellows was a caution!" exclaimed Dunk. "Seems as though he'd have enough to worry along on without stealing."

"He spent a lot, though," said Andy. "He was used to high living and I suppose when he found the money wasn't coming from his father any more he had to get it the best way he could."

"Or the worst," commented Dunk, grimly. "I know he never paid me back all he got, and the same way with a lot of the fellows. But if he's coming I wish he'd show up. I don't wish him any bad luck, and I'd give a whole lot, even now, if it would prove to be someone else besides Mortimer. But I'm getting tired of waiting here."

"So am I," said Andy, with a yawn.

Again there was a silence, while they kept their strange vigil. Then, far down the lower corridor, there sounded footsteps.

"He--he's coming!" whispered Andy in a tense voice.

"Yes," a.s.sented Dunk.

But it was a false alarm. As the footsteps came nearer the waiting lads saw one of the janitors on his rounds. He did not see them, and pa.s.sed on.

Andy was doing some hard thinking. The suggestion made by Dunk that the capture of the thief would be more of a black spot for Yale than the fact of the robberies taking place was bearing fruit.

"But what can we do?" Andy asked himself. "We've got to stop these thefts if we can, and the only way is to catch the fellow who's doing it."

They had been in their hiding place nearly an hour, and were getting exceedingly weary. Dunk shifted about, as did Andy, and it was on the tip of the latter's tongue to suggest that they give up their plan for the night when they heard a distant door opened cautiously.

"Listen!" whispered Andy.

"All right," a.s.sented his chum. "I hope it amounts to something."

With strained ears they listened. Now they heard steps coming along the corridor. Curious, shuffling steps they were, not hard, honest heel-and-toe steps--rather those of someone treading softly, as on soles of rubber.

"It's him all right this time!" whispered Andy in Dunk's ear.

"I guess so--yes. Shall we follow him?"

"Yes. Take off your shoes."

Silently they removed them, and waited. The steps were nearer now, and a long shadow was thrown athwart the place where Andy and Dunk were hiding. They could not recognize it, however.

The shadow came nearer, flickering curiously as the swaying of an electric lamp threw it in black relief on the corridor floor.

Then a figure came past the recess where the two lads were concealed.

They hardly breathed, and, peering out they beheld Mortimer Gaffington stealing into Wright Hall.

It was only what they had expected to see, but, nevertheless, it gave them both a shock.

Mortimer moved on. They could see now why he could walk so silently. He had on rubbers over his shoes. The same trick used by the thief who had entered Frank's room.

Mortimer looked all around. He stood in a listening att.i.tude for a moment, and then, as if satisfied that the coast was clear, started up the stairs toward the corridor from which opened the room of Andy and Dunk.

The two waited until he was out of sight, and then followed, making no more noise than the thief himself. They timed their movements by his.

When he advanced they went forward, and when he stopped to listen, they stopped also. It was like some game--a very grim sort of game, though.

There was only a dim light in the upper corridor, and, coming to a halt where the shadows were deepest, Andy and Dunk watched. They saw Mortimer stop before a student's door, try it and then came the faint tinkle of a bunch of keys.

"Skeletons," whispered Dunk.

Andy nodded in a.s.sent.

The manipulation of the lock by means of a false key seemed to come easy to Mortimer. In a moment he was inside the room. What he did there Andy and Dunk could not see, but he remained but a few minutes, and came out, softly closing the door after him.

"I wonder what he got?" whispered Dunk.

"We'll soon know," was Andy's answer.

Mortimer went softly down the corridor. He did not try every door, but only went in certain rooms, and these, the two watchers noticed, were those where well-to-do students lived.

Mortimer made four or five visits, and then moved towards the apartment of Andy and Dunk.

"It's our turn now," whispered the latter.

Silently they turned a corner, just in time to see Mortimer enter their room.

"Now we've got him!" exulted Andy.

"Not yet; we've got to nab him," whispered Dunk. "Oh, Andy, this is fierce! To think that we're spying on a Yale man! To think that a Yale man should turn out to be a common thief! It makes me sick!"

"Same here," sighed Andy. "But the only way to stop suspicion from falling on others is to get Mortimer with the goods. We've got to save Link, too."

"That's right," a.s.sented Dunk. "He isn't a Yale man, but he's a heap better than the kind in there." He nodded his head in the direction of their room, where Mortimer now was.

They had left a light burning, and could see, as its beams were cut off now and then, that the intruder was moving about in their apartment.

"Come on, let's get him--and have it over with," suggested Dunk.