rom another. You may go."

There was little in the nature of a scolding in this address, and yet
something in it caused every one to leave the room in a state of great
excitement. Acton and Jack Vance especially fairly boiled with wrath.

"What old Welsby says is quite right," remarked the latter; "and until
those things are found, we may all be looked upon as thieves."

The search, however, proved fruitless; and, what was worse, in turning
over the contents of the shed, Acton discovered that a bull's-eye
lantern belonging to himself had disappeared from the shelf on which it
usually stood; while Mugford declared that a box of compasses, which he
had brought down a few days before to draw a pattern on a piece of
board, was also missing.

Directly after tea Acton button-holed Diggory, and taking him aside
said, "Look here, I'm in an awful rage about these thing's being
prigged, because, of course, I've got the key of the shed; and didn't
you hear what old Welsby said about it? It looks uncommonly as if I
were the thief. You remember what you said the other night when we had
that feed, about seeing that man? D'you think there _is_ any one who
comes here at night and steals things?"

"Well, I'm certain I saw some one in the playground when I told you.
It was a man; but whether he comes regularly and goes into the shed I
don't know, but I think we ought to be able to find out."

"How?"

"Oh, some way or other; I'll tell you to-morrow." That night, long
after the rest of the house were asleep, the Triple Alliance lay awake
engaged in earnest conversation; and in the morning, as the boys were
assembling for breakfast, Diggory touched Acton on the shoulder and
whispered,--

"I say, we've thought of a plan to find out if any one goes into the
shed at night."

"Who's 'we'?"

"Why, the Triple Alliance; we thought it out between us. Sneak out of
the house directly after evening 'prep,' and meet me in the playground,
and I'll show you what it is."

At the time appointed Acton ran down the path, and found Diggory waiting
for him by the shed.

"Look," said the latter, "I've cut a little tiny slit with my knife in
each door-post, about three feet from the ground, and I'm going to
stretch this piece of black cotton between them. No one will see it,
and if they go through the door, the thread will simply draw out of one
of the slits without their noticing it, and we shall see that it's been
disturbed. Jack Vance