This came that very afternoon while he was working at the bottom of the deep cut through the spur of the hill which marked the top of the long, stiff grade just west of the mill switch.  
The other members of the gang were at the farther end of the cut, and Allan had just finished levelling down a pile of , when he heard a sudden shout of warning from .
 
“Look out, Allan!” cried the latter. “Look out!”
 
Allan sprang aside, and was just in time to escape a large which came crashing down the side of the cut.
 
Allan gazed at it in , drawing a deep breath at his escape. Then he saw Jack, followed by the others, charging madly up the side of the hill. Without stopping to reason why, he followed.
“What’s the matter?” he cried, as he came panting up behind the ones who had just gained the hilltop.
 
“Matter!” cried Jack, glaring around to right and left over the hillside. “Matter enough! What d’ y’ suppose made that rock fall that way?”
 
“Why,” said Allan, looking around bewildered, “the earth under it must have given way—”
 
“Nonsense!” interrupted the foreman, impatiently. “Look, here’s th’ hole it left. Th’ earth didn’t give way a bit. Y’ see th’ rock was out—yes, an’ here’s th’ rail that was used to do it with. Now, who d’ y’ suppose had hold of that rail?”
 
Allan turned a little giddy at the question.
 
“Not Dan Nolan?” he said, in an whisper.
 
“Who else but Dan Nolan. An’ he’s hidin’ down there in one o’ them gullies, sneakin’ along, keepin’ out o’ sight, or I’m mistaken.”
 
“Did you see him?” asked Allan.
 
“No, I didn’t see him,” retorted Jack. “If I’d seen him, I’d have him in jail afore night, if I had t’ hunt this whole county over fer him. But I know it was him. Who else could it be? You know he’s threatened y’. He’s been hangin’ around doggin’ y’ ever since I put y’ at this job. There’s more’n one of us knows that; an’ there’s more’n one of us knows, too, that he wouldn’t be above jest this kind o’ work. He a man on my gang, onct, jest because he had a ag’in him—dropped th’ end of a rail on his foot an’ it so bad that it had t’ be taken off. He said it was an accident, an’ I believed him, fer I didn’t know him as well then as I do now. He wouldn’t stop at murder, Dan Nolan wouldn’t—why, that rock would ’a’ killed you in a minute, if it had hit you!”
 
“Yes, I believe it would,” said Allan, and he shivered a little at the thought of his narrow escape.
 
Jack took another long look around at the hills and valleys, but if Nolan was anywhere among them, the trees and underbrush hid him effectually. And Allan was loth to believe Jack’s theory; bad as Nolan was, it seemed incredible that he should be so , so cold-blooded, as to lie there on the of the , waiting, moment by moment, until his victim should be in the precise spot where the rock would strike him. That seemed too fiendish for belief.
 
“I wouldn’t like to think Nolan did it,” he said, a little , “unless I had some proof. You didn’t see him, you know—”
 
“See him!” echoed Jack. “No—I didn’t need to see him! There’s th’ hole th’ stone was pried out of, an’ there’s th’ rail that was used fer a lever. Now who had hold o’ that rail? Ain’t Nolan th’ only enemy you’ve got in th’ world?”
 
“Yes,” said Allan, in a low voice; “yes, I believe he is.”
 
“An’ do you suppose a feller would lay fer you like that unless he had somethin’ ag’in you? I tell you, Dan Nolan’s hidin’ down there in the bushes somewhere, an’ lookin’ up here at us an’ swearin’ because he didn’t git you!” and Jack shook his fist impatiently at the horizon. “If I had him under my heel, I’d kill him like I would a snake!”
 
Which, of course, Jack wouldn’t have done, but his honest Irish blood was boiling at this moment, and he said more than he meant.
 
“Come on, boys,” he added, calming himself by a effort, “we can’t ketch him now, but we’ll git th’ scoundrel yet!” and he started down the hill, a savage still on his face.
 
The incident had cast a shadow over the spirits of the gang, and they worked the rest of the afternoon in silence. Indeed, ever since Reddy’s accident, the gang had lacked that spirit of optimism and gaiety which had marked it; a new man had been taken on, but while he did Reddy’s work fairly well, he could not take Reddy’s place in the hearts of the men. Their day’s work lacked the savour which Reddy’s wit had given it, and they went home at night more weary than had been their . Jack saw, too, that their work had lost some of its , and yet he had no heart to find fault with them.
 
But he took no more chances of Allan’s suffering any injury. He had talked the matter over with his wife, and between them, they had laid out a plan of action. Whenever possible, Jack kept Allan near him. When that was not possible, he took care that the boy should not be alone at any spot where his enemy could up on him from behind. He knew if the boy was injured through any carelessness or lack of on his part, he would never dare to go home again and face his wife!
 
All of this was, of course, plain enough to Allan, and him somewhat, for he did not want the rest of the gang to think him a baby who needed constant looking after. Besides, he had an honest reliance on his ability to look after himself. So, one day, he ventured to protest.
 
“See here, Jack,” he said, “I’m not afraid of Dan Nolan. In fact, I think I’d be rather glad of the chance to meet him in a fair stand-up fight.”
 
“An’ that’s just th’ chance he’ll never give ye,” retorted Jack. “I wouldn’t be afeerd o’ him, either, if he’d fight fair—I believe y’ could lick him. But he won’t fight fair. Th’ coward’ll hit y’ from behind, if he kin—an’ he’s waitin’ his chance. That’s his kind, as y’ ought t’ know by this time. Oh, if I could only ketch him!”
 
But since the afternoon that great rock had fallen, Nolan had disappeared from his accustomed haunts. Jack made , but could get no news of him. The gang of scalawags who were his usual companions to be utterly ignorant of his whereabouts. He had been sleeping in a little closet back of one of the low railroad saloons, paying for board and by cleaning out the place every morning, but the of the place said he had not been near there for a week. So at last Jack dropped his inquiries, hoping against hope that Nolan had taken alarm and left the neighbourhood.
 
Reddy continued to improve from day to day, but mentally he grew worse and worse. His broken arm had healed nicely, and the wound in his head was quite well, but the injury to the brain baffled all the skill of his physicians. He would sit around the house, moping, seemingly taking notice of nothing; then he would sud............