Two trustworthy men had been selected from the night shift to keep guard on the lower level during the time between sunset and sunrise, and about an hour before the relieving whistle sounded, not having heard any suspicious noises, they lounged down toward the slope where the miners were at work.

Here, paying but little attention to what was going on around them, they conversed with the laborers, or smoked pipes as black as their faces, in order to while away the moments which must elapse before the labor was ended.

Men were passing and re-passing on every hand, and in the darkness no one saw a small figure, in whose cap the lamp was not lighted, run swiftly from the foot of the slope up the drift where the sentinels should have been.

On either side of the passage shallow cuttings had been made that the miners might step aside to avoid the cars as they were drawn to and fro. Into one of these the figure with the unlighted cap glided, and, crouching in the farthest corner was screened from view unless a careful search should be made.

When the day shift came on duty Chunky reported to the breaker boss that Skip Miller could not come to work on this day.

"Why not?" Donovan asked sharply.

"'Cause he's got to do somethin' at home. He told me to tell you."

"When did you see him?"

"Last night."

"Where?"

"Over by Taylor's."

"What were you doin' at that grogshop?"

"Nothin'. I was jest walkin' around, an' met him."

"Look here, Chunky, it will be best for you to keep away from that place. No decent man or boy would go there, an' I'd be sorry to know you trained with the regulators. I've got my eye on them fellers, an' when trade is dull they'll be the first to get their walkin' papers."

"If father don't care what I do, it ain't any business of yours, so long as I work from whistle to whistle."

"That's very true; but I shall make it my business to see what your father has to say about it."

This threat had the effect of checking the almost insolent air Chunky had begun to display, and he went to his place at the chute very meekly.

While this brief conversation was being held Joe and Bill, with their helpers, entered the lower level where the careless sentinels reported matters as being quiet.

"We haven't heard more'n a rat since you left," one of them said. "I don't believe Billings has got the nerve to try any funny business, an' in this case Mr. Wright is more frightened than hurt."

"That's a good fault, matey," Bill replied gravely. "It's better to have half a dozen of us nosin' around for a week or two, than run the risk of what Cale an' his friends may do."

"Oh, I ain't kickin'; but it don't seem reasonable they could get into the old drift, for it must be choked with gas."

"By findin' that out we might save a good deal of work," Joe replied, quickly. "It wouldn't take long to cut through where the wall is thinnest."

"You're right mate, an' we'll get at it now. Boys, go over to the blacksmith's for four shovels," Bill added as he pulled the plans from his pocket.

Sam and Fred obeyed, and while they were absent the two men studied the drawing for at least the hundredth time.

Save for those who were seated on a block of coal poring over the paper, the drift was deserted, and the one who had secreted himself in the cutting crept silently forward until it was possible to see what the miners were doing.

As a matter of course this party was Skip Miller, and he said to himself, with a chuckle of satisfaction:

"With all day before me it'll be queer if I can't get what Billings wants."

When Sam and Fred returned Bill had decided at which point the excavation should be made, and he said, designating a spot hardly more than a dozen yards from where Skip was hidden:

"If the plan is co'rect this oughter be our place. We'll try it anyhow. You boys tell one of the drivers to bring up a car, for we don't want to choke the drift with dirt."

Then Bill stuck his pick in the wall, which was made up of earth and slate. Skip, who sat directly opposite, had a full view of all that was done.

When the car had been brought into position Bill told Sam and Fred to shovel into it what he and Joe threw from the cutting, and soon all four were working industriously.

Before the time for "nooning" arrived it became necessary to shore up the top of the tunnel lest the mass of earth should fall and bury the laborers, and when this was done both the men entered the excavation, which was now twelve feet in length.

In this confined space the air was oppressively warm, and the miners threw off their blouses, leaving them in the drift near the entrance.

Skip knew that in the pocket of the one worn by Bill was the paper he had been instructed to steal, and he watched eagerly for an opportunity to creep up unobserved.

While Sam and Fred were at work it was impossible to do this; but the car had been nearly filled, and in a short time it would be necessary to get another.

The men could no longer throw the dirt from where they were working to the entrance, and Fred had been ordered to stand midway the cutting that he might pass it on to Sam.

"I'll run this car down, an' get another if you'll give me a lift at starting it," Sam finally shouted, and Fred came out.

The incline was sufficient to carry the rude vehicle to the switches at the foot of the slope after it was once set in motion, and, using a crowbar as a lever, this was soon accomplished.

Sam ran behind it a few paces, and then clambered up to the brake where he could control the movements of the heavy load.

Fred watched him until the tiny flame in his cap was lost to view in the distance, and then he returned to the tunnel, unconscious that Skip had glided from his hiding-place to follow closely behind.

It was necessary the leader of the regulators should work with the utmost celerity, for if Fred turned he would distinguish the dark form even in the gloom.

Skip had already formed a plan.

He crept close behind the boy whom he hated, until the latter entered the tunnel. Then stooping he picked up the crowbar, and raised it for a blow. In this position he waited until Fred was in the middle of the tunnel clambering over the pile of dirt to get at his shovel.

The time had come.

Swinging the heavy bar once around he struck the bottom of the joist which supported the shoring over head, and the heavy timbers, put up insecurely because they were to be used but temporarily, fell with a crash.

The jar disturbed the earth at the top, and large masses fell, completely filling the entrance, burying alive those who were on the inside.

"That settles them, I reckon," Skip cried, gleefully, as, unmindful of the blinding dust, he sprang toward Bill's blouse.

To find the plan of the mine was but the work of a moment, and then, with the precious document thrust in the bosom of his shirt, he started at full speed toward the entrance to the slope.

The crash of the timbers and earth was by no means an unusual sound in the mine, where heavy masses of coal were constantly being detached by blasts, and the leader of the regulators had good reason to believe it would be unnoticed. His only care was to avoid Sam, in case he should return sooner than might be expected, and to this end he darted from one cutting to another, until having reached a point from which, at the proper moment, he could gain the slope.

Here he remained partially screened from view until the empty car, which Sam was to send to the new cutting, had passed on its way up the drift.

Now he listened intently, and in a few moments came the cry:

"A break! A break, and three men buried! Help on the lower level!"

Those who were near enough to hear this appeal sent the alarm from drift to drift up the slope, until the entire mine seemed to be ringing with the words:

"Help is needed on the lower level!"

In view of all that happened, together with the knowledge that if any attack was made by the Billings' gang it would be on the lower level, every workman ran with all speed to the bottom of the slope, and among the foremost was Mr. Wright.

"What has happened?" he asked of a blacksmith, who was darting toward the chamber in which the tools were stored.

"Bill Thomas, Joe Brace, and a butty are buried in a cutting the fools were makin' up there a piece."

"Go back," Mr. Wright cried to the swarm of men which came down the slope like a living stream. "Not more than twelve can work to advantage, and we have that number here."

"But we want to do our share," an old miner replied.

"You shall have a chance if we do not find them soon. It is not safe to have so many here at once."

All hands understood the reason for this caution, and as the crowd turned to ascend Skip Miller slipped from his hiding place and joined them. He did not fear detection while every one was in such a state of excitement, and even if he should be recognized it would be only natural for him to have followed the men at the first alarm.

It was necessary, however, that he should avoid Donovan, and with the utmost caution he emerged from the slope, running as fast as his legs would carry him on reaching the open air.

Not until Taylor's groggery was near at hand did he slacken speed, and then, assuming as best he could an air of composure, he opened the door cautiously to peep in.

Cale Billings was the only customer, and on seeing Skip, he cried:

"Come in, lad. I reckon you're here to see me."

Struggling hard to prevent his heavy breathing from being observed by the proprietor, the leader of the regulators entered, and whispered:

"There's been an accident on the lower level, an' two or three shut in."

"Explosion?"

"The top of the cuttin' fell in, an' it won't be a easy job to dig em out."

"Was you there?"

Sam nodded his head in a triumphant manner.

"You're a lad after my own heart," Billings said, approvingly, as he extended a huge, grimy hand for the boy to shake. "If half the men here had your spunk Wright wouldn't have got the best of us so easy. Did you fix that thing I told you about?"

Skip nodded his head, and again Billings shook his hand.

"That's what I call business. Let's have it."

The leader of the regulators was about to draw the dearly-earned document from his pocket when the proprietor of the place interfered.

"None of that," he said sharply. "There's somethin' goin' on what ain't straight, an' I won't have it in my shop."

"Do you mean to go back on a friend?" Billings asked in an injured tone.

"Not a bit of it; but the company are lookin' after you mighty sharp, Cale, an' I don't want to get in trouble. There's plenty room out of doors."

"All right, the shop belongs to you; but it may be the losin' of a good customer," and Billings walked out with Skip close at his heels.

"Now give me the paper."

When the document was delivered the man glanced at it to make sure it was the one wanted, and then said in a fatherly tone:

"I reckon you've fixed things to suit yourself if the new breaker boy was in the cuttin' when the roof fell."

"They're diggin' for him now; but I'm goin' to get the worst of this job."

"How so?"

"Taylor will blow the whole thing, an' then Wright will know it was me."

"Ain't I here to protect yer?"

"Yes; but——"

"Don't worry, my son. Go into the breaker as if nothin' had happened."

"I can't 'cause I sent word I wouldn't come to-day."

"Then keep out of sight till night, and meet me on the railroad track after dark. We'll have this job mighty nigh done before morning."

Billings was walking toward the slope, and not daring to follow him any farther, Skip ran swiftly in the opposite direction, wondering where he could hide until sunset. For the first time he began to fear the consequences of his cruel deed, and the thought that the officers of the law might soon be in search of him was by no means reassuring.

He sought the shelter of the thicket farther up the hill where a view of the slope could be had, and there he waited, expecting each moment to see lifeless bodies brought from the mine.