says that when he's been out shooting with his
guv'nor he's seen the keeper put them across the paths in a wood to find
out if poachers have been up them. Now unlock the door, and let's go
inside."

In front of the bench, where the ground had been much trodden, there was
a great deal of loose dust. Diggory went down on his hands and knees,
and producing an old clothes-brush from his pocket, swept about a square
yard of the ground until the dust lay in a perfectly smooth surface.

"There," he said, rising to his feet again; "we'll do this the last
thing every night, and any morning if we find the cotton gone we must
look here for footprints, and then we ought to be able to tell if it's
a man or a boy."

"Don't you think we ought to tell Blake about that man you saw?" asked
Acton, as they walked back to the schoolroom.

"Well, I don't see how we can," answered Diggory. "The first thing
he'll ask will be,' Who saw him?' I shall say, 'I did;' and then he'll
want to know how I saw the playground door from my bedroom window, which
looks out on the road; and then the fat'll be in the fire, and it'll all
come out about that supper."

Regularly every evening, as soon as supper was over, the two boys stole
down into the playground to set their trap; but when morning came there
was no sign of the shed having been entered. This went on for nearly a
month, but still no result.

"I don't think it's any good bothering about it any more," said Acton;
"the thief doesn't mean to come again."

"Well, we'll set it to-night," answered Diggory, "and that shall be the
last time."

The following morning Acton was sauntering towards the playground, when
Diggory came running up the path in a state of great excitement.
"I say, the cotton's gone!"

Acton rushed down, unlocked the door of the shed, and went inside.

"Hullo!" he exclaimed, as Diggory followed; "_it is_ some man. Look at
these footprints, and hobnailed boots into the bargain!"

CHAPTER V.

CATCHING A TARTAR.

It was impossible for two boys to keep such an important discovery to
themselves, and the shed was soon filled with an eager crowd, all
anxious to view the mysterious footprints. The Triple Alliance
gained fresh renown as the originators of the scheme by which the
disclosure had been made, and it was unanimously decided that the matter
should be reported to Mr. Blake.

The master cross-questioned Acton and Diggory, but seemed rather
inclined to do