the plan it was made to conform so perfectly to this
theory that he felt satisfied his conclusions were correct, and
consequently made his confident statements to Mr. Jones.

The latter had been connected with the Raven Brook Colliery but a few
months, and knew nothing of its old and abandoned workings, not yet
having found time to study their plans or explore them. He did know,
however, that Mr. Sterling had been one of the company's most trusted
engineers, and that Derrick had long been interested in poring over and
tracing his father's plans of these very workings. When, therefore, he
had carefully examined the tracing that the boy had made, and now
assured him was an exact copy of the original plan, and found that it
showed a system of galleries by which the top of the air-shaft might be
gained from the break, he had no hesitation in saying that they would
make the attempt to reach it from that direction. Had he sent for the
original plan he would have quickly discovered Derrick's error. He
thought of doing this, but did not, for fear of wounding the lad's
feelings by appearing to mistrust him.

It was arranged between them that Mr. Jones should leave the village on
the afternoon of the 27th, as though bound on some distant expedition,
and have it understood that he might possibly be absent all night. An
hour before sundown he was to be at the break, prepared to explore the
old gangway to which it gave entrance. Here Derrick was to meet him,
after having left the mine an hour earlier than usual, gone home for
supper, and told his mother that he should be out late on some business
for the mine boss.

This plan was successfully followed, without suspicion being aroused,
and the young mine boss met his boy companion at the appointed time and
place. They both had safety-lamps, and each carried a small can of oil,
for they did not know how long they might have to remain in the mine.

In the break they found a rickety ladder that had been placed there for
the use of the village children, who were accustomed to come here with
baskets, and in a small way mine coal for home use from the sides of the
old gangway. Descending this, they lighted their lamps at the bottom,
and entering the black opening began to follow the path marked out on
Derrick's tracing.

For some distance the way was comparatively smooth, and they made rapid
progress. Then they began to encounter various obstacles. Here a mass of
rock had fallen from