the flooring of
dirt gave way beneath his feet.

Half suffocated by the gas, and overwhelmed by the falling fragments, he
hardly realized what had occurred until finding himself in what was
unmistakably another and yet lower tunnel or drift.

CHAPTER XV

A DISCOVERY

After the first alarm passed away, Fred understood that he had fallen
but a few yards, and the earth which covered him represented only a very
small portion of the upper tunnel's floor.

Scrambling to his feet he fancied for a moment that the sound of
scurrying footsteps could be heard, and while listening, Joe said:

"Hello! Are you hurt?"

"Not a bit."

"Where are you?"

"It seems like a regular cutting, and the air is pure."

"Light your lamp an' look around."

Obeying this command, Fred found his suspicions correct, and so
reported.

"Can you get back?"

"Not unless you pull me up."

"We'll attend to that in a minute."

The rush of air from below had so far checked the gas, now partially
shut off, that the men could also light the lamps in their caps, and
the remainder of the task was quickly accomplished.

With a couple of timbers as braces the aperture to the old mine was
closed securely, and then the attention of the men was turned to the
boy.

"Look out down there!" Bill shouted. "I'm goin' to drop a couple of
joists so's we can come back."

"Let them go."

"Now drag 'em out of the way, an' we'll follow."

When this had been done the men and Sam descended, all completely
mystified by this new discovery.

"Here's somethin' that I reckon Mr. Wright didn't know about," Bill
said, as he surveyed the scene, and then he added with great emphasis as
a sudden thought occurred to him. "Now we can come pretty nigh guessing
what them noises meant. Some one has been tryin' to get into the other
level, an' when a big hole was made Fred put an end to the work by
fallin' through."

This could be told by the mound of earth a short distance away, as well
as by the marks of a pick around the edges of the aperture; but further
proof was found in the shape of a shovel which Sam stumbled over.

"This belongs to the company," he cried, pointing to the brand.

"Yes, an' a blind man can figger who's been here. Cale Billings didn't
leave town as he tried to make folks believe."

"Then let's have him. This cuttin' can't be so long but that we'll get
all over it before sunset," Joe cried, as he wrenched the shovel handle
from the i