IT was twenty-four hours later. A half mile away, along a road that showed like a grey thread in the night, twinkled a few lights from the little cluster of houses that made the town of Bald Creek. At the rear of the station itself, in the shadow of the walls, it was inky black.

There was stillness! Then the chattering of a telegraph instrument—and, coincident with this, low, scarcely audible, a sound like the gnawing of a rat.

The chattering of the instrument ceased; and, coincident again, the low, gnawing sound ceased—and, crouched against a rear window, the Hawk chuckled a little grimly to himself. Within, and diagonally across from the window, an otherwise dark interior was traversed by a dull ray of light that filtered in through the open connecting door of the operator's room beyond. Inside there were Lan-son, the division superintendent, and Martin, the trusted Bald Creek operator; while at any minute now, MacVightie would be up on No. 12. They were preparing to spring their trap for the Wire Devils to-night! The Hawk was quite well-informed on this point, for the very simple reason that the Hawk himself had not been entirely idle during those twenty-four hours that were just past!

Again the sounder broke into a splutter; but this time the gnawing sound was not resumed—the window fastenings were loosened now.

Came then the distant rumble of an approaching train; the rumble deepening into a roar; the roar disintegrating itself into its component sounds, the wheel trucks beating at the rail joints, the bark of the exhaust; then the scream of the brakeshoes biting at the wheel tires; the hiss of steam—and in the mimic pandemonium, the Hawk raised the window, and crawled in over the sill.

And again the Hawk chuckled to himself. Up and down the line to-night, at all stations where there were no night operators, the road's detectives, stood guard over the telegraph instruments. It had been MacVightie's plan, originated the night before. It was very clever of MacVightie—if somewhat abortive! Also, quite irrelevant of course, and quite apart from that little matter of ten thousand dollars which he, the Hawk, had taken from the paymaster's safe last night, MacVightie to-night was likely to be in no very pleasant mood!

The engine without, blowing from a full head of steam, drowned out all other sounds. The Hawk picked his way across the room to a position near the connecting door, and composedly seated himself upon the floor behind a number of piled-up boxes and parcels. With a grin of acknowledgment to the escaping steam, he coolly moved two of the parcels a few inches to right and left, thus providing himself with an excellent view into the operator's room. From one pocket he took an exceedingly small flashlight, and from another a notebook, and from his hip pocket his automatic pistol. This latter he transferred to his right-hand coat pocket. Bunching the bottom of his coat over his hand, he flashed on the tiny ray, found a convenient ledge formed by one of the boxes, and upon this laid down his notebook. The first page, as he opened the book, contained a neatly drawn sketch of the interior of Bald Creek station. He turned this over, leaving the book open at a blank page, and switched off his light.

The door from the platform opened and closed, as the train pulled out again, a man stepped into the operator's room—and in the darkness the Hawk smiled appreciatively. It was MacVightie, and Mac-Vightie's thin lips were drawn tighter than usual, and the brim of the slouch hat, though pulled far forward, did not hide the scowl upon MacVightie's countenance.

“Well, you're here all right, Lanson, eh?” he flung out brusquely. “Nothing yet, by any chance, of course?”

Lanson, from a chair at the operator's elbow, nodded a greeting.

“Not yet,” he said.

MacVightie was glancing sharply around him.

“Martin,” he ordered abruptly, “close those two ticket wickets!”

The operator rose obediently, and pulled down the little windows that opened, one on each side of the office, on the men's and women's waiting rooms.

“What's that door there?” demanded MacVightie, pointing toward the rear room.

“Just a place I had partitioned off for stores and small express stuff,” Martin answered. “There's no back entrance.”

“All right, then,” said MacVightie. He pulled up a chair for himself on the other side of the operator, as Martin returned to his seat. “You know what you're here for, Martin—what you've to do? Mr. Lanson has told you?”

“Yes,” Martin replied. “I'm to test out for east or west, if there's any of that monkeying on the wire to-night.”

“Show me how it's done,” directed MacVightie tersely. .

The operator reached over to the switchboard and picked up a key-plug.

“I've only got to plug this in—here—or here. Those are my ground wires east and west. The main batteries are west of us at Selkirk, you know. If I ground out everything east, for instance, and he's working to the east of us the sounder'll stop because I've cut him off from the main batteries, and we'll hear nothing unless I adjust the relay down to get the weak circuit from the local batteries. If he's working west of us the sounder will be much stronger because the main batteries at Selkirk, with the eastern half of the division cut out, will be working on a shorter circuit.”

“'T see.” MacVightie frowned. “And he'd know it—so Mr. Lanson told me last night.”

“Yes; he'd know it,” said Martin. “The same as we would.”

“Well, you can do it pretty quick, can't you?” suggested MacVightie. “Sort of accidentally like! We don't want to throw a scare into him. You'd know almost instantly whether he was east or west, wouldn't you? That's all that's necessary—to-night! Then let him go ahead again. We'll have found out what we want to know.” He turned to Lanson, his voice rasping suddenly. “Did you see the Journal on the 'Crime Wave' this afternoon?”

Lanson's alert, grey eyes took on an angry glint. “No; I didn't see it, but I suppose it's the old story. I wish they'd cut it out! It hurts the road, and it doesn't get them anywhere.”

“Perhaps not,” said MacVightie, with a thin smile; “but it gets me! Yes, it's about the same—all except the last of it. Big headlines: 'Ten thousand dollars stolen from paymaster's safe last night—What is being done to stop this reign of assassination, theft, outrage, crime?—Has the clue afforded by the Hawk's release from Sing Sing been thoroughly investigated?' And then a list of the crimes committed in the last ten days—two murders, one in the compartment of that sleeping car; the theft of the diamond necklace; the express robbery; and so on through the list, ending up with last night. Then a nasty shot at the local police; and, finally, prefacing the remark with the statement that the crimes were all connected with the railroad, a thinly veiled hint that I am either a boy on a man's job, or else asleep, in either of which cases I ought to be—well, you understand?” MacVightie's fist came down with a crash on the operator's table.

Lanson, with a worried look, nodded his head.

“Damn it!” said MacVightie. “I——” He stopped abruptly, and laid his hand on the operator's sleeve. “Look here, Martin,” he said evenly, “you're the one man that Mr. Lanson has picked out of the division, you're the one man outside of Mr. Lanson and myself who has any inkling that these secret messages coming over our wires have anything to do with these crimes—you understand that, don't you? This is pretty serious business. The newspaper didn't exaggerate any. We're up against a gang of crooks, cleverly organised, who will stop at nothing. Murder appears to be a pastime with them! Do you get me—Martin?”

For a long second the two men looked each other steadily in the eyes.

“Yes,” said Martin simply.

“All right!” said MacVightie. “I just want you to realise the necessity of keeping anything you may hear, or anything that may happen here to-night, under your hat.” He turned to Lanson again, the scowl heavy upon his face once more. “I was going to say that I know who the man is that slipped through my fingers last night.”

“You—what!” Lanson leaned sharply forward in his chair. “But he got away! You said he——”

“It was the Hawk”—MacVightie bit off the words.

“The Hawk?”

“The Hawk!”

“But how do you know?” demanded Lanson incredulously. “You said yourself that he had left no clue to his identity. How do you know?” MacVightie reached into his pocket, took out his pocketbook, and from the pocketbook passed a new, crisp ten-dollar banknote to Lanson.

“What's this?” inquired Lanson. “The counterfeit ten-dollar bill you showed me last night?”

“No—another one,” MacVightie answered curtly. “Look on the other side.”

Lanson turned the banknote over, stared at it, and whistled suddenly under his breath.

“'With the compliments of the Hawk!'.rdquo; he read aloud. He stared now at MacVightie. “Perhaps it's a fake, inspired by that newspaper article yesterday evening,” he suggested.

“It's no fake,” declared MacVightie grimly. “The Hawk wrote that there all right—it was inside the pay bag in which the ten thousand was carried away from the paymaster's office last night.”

“You mean—you recovered the bag?” cried Lanson eagerly. “Where? When?”

The Hawk, watching MacVightie's face, grinned wickedly. MacVightie's jaws were clamped belligerently, and upon MacVightie's cheeks was an angry flush.

“Oh, yes, I 'recovered' it!” MacVightie snapped. “He's got his nerve with him! The bag was found reposing in full view on the baggage counter at Selkirk this afternoon—addressed to me. Nobody knows how it got there. But”—MacVightie's fist came down again upon the operator's table—“this time he's overplayed his hand. We knew he had been released from Sing Sing, and that he had come West, but it was only surmise that he was actually around here—now we know. In the second place, it's pretty good evidence that he's in with the gang that's flooded the country with those counterfeit tens, and you'll remember I told you last night I had a hunch it was the same gang that was operating out here—well, two and two make four!”

“You think he's——?” Lanson swept his hand suggestively toward the telegraph instruments.

“Yes—and the leader of 'em, now he's out here on the ground!” returned MacVightie gruffly.

The Hawk had taken a pencil from his pocket, and was scribbling aimlessly at the top of the page in his notebook.

“Sure!” confided the Hawk to himself. “I thought maybe you'd dope it out like that.”

There was silence for a moment in the office, save for the intermittent clicking of the sounder, to which the Hawk now gave his attention. His pencil still made aimless markings on the top of the page—it was only routine business going over the wire. Then Lanson moved uncomfortably in his chair, and the chair legs squeaked on the bare floor.

MacVightie spoke again:

“Well,” he said bluntly, “you've got all of my end of it, except that I've placed men in hiding at every station on the line where there are no night operators. What about you? Started your outside line inspection?”

“Yes,” Lanson answered. “I've had three men out with section crews working from different points. But it's slow business making an inspection that's careful enough to be of any use, and even then it's a pretty tall order to call the turn on anything when there's already so many legitimate splices and repairs on the wires.”

“Well—any results?” asked MacVightie.

Lanson shook his head.

“We found what we thought was a new splice in one place, but it turned out to have been made by one of our own men two weeks ago, only he had forgotten to report it.”

MacVightie's eyes narrowed.

“One of our own men—eh?” he repeated curtly. “Who was it?”

“Nothing doing there!” Lanson shook his head again, emphatically this time. “It was Calhoun.”

“Calhoun—eh?” observed MacVightie softly.

Lanson bridled slightly.

“What's the matter with Calhoun?” he inquired testily. “Got anything against him?”

“Never heard of him before,” said MacVightie, with a short laugh. “But I'll take pains to make his acquaintance.”

“Then you might as well spare yourself the trouble,” advised Lanson. “I can tell you before-hand that he carries a good record on this division, and that he's one of the best linemen we've got.”

“I daresay,” admitted MacVightie coolly. “But amongst other things we're looking for good linemen to-night—who forget to make reports. You needn't get touchy, Lanson, because one of your men's names comes up. You can make up your mind to it there's an inside end to this, and——”

The tiny ray of the Hawk's flashlight shot suddenly upon the notebook's open page, as the sounder broke into a sharp tattoo.

“;wtaz'—stroke at four,” he muttered, as he began to write. “Three—one—two. They've changed the code to-night—'qxpetlk——'”

There was a sharp exclamation from the other room.

“Listen! There he is now!” Martin cried. Chairs were pushed back—the three men were on their feet.

“What's he sending?” questioned MacVightie instantly.

The Hawk scowled at the disturbance, as, over their voices, he concentrated his attention upon the sounder. He wrote steadily on:

“... huwkmuh hdtlqgvh...

“Same as usual,” Martin replied. “Just a jumble of letters.”

“Well then, get ready to throw that ground, or whatever you call it, into him!” ordered MacVightie tensely.

“I'm ready,” said Martin.

“All right then—now!”

The Hawk nodded to himself, as his pencil unflaggingly noted down letter after letter. The sounder was very perceptibly stronger.

“West!” Martin cried out. “You noticed the difference in strength, didn't you? He's somewhere between here and Selkirk. That's——”

The sounder had suddenly ceased.

“But he's stopped,” said MacVightie; “and you said if he stopped——”

“That's nothing to do with it!” Martin interposed hurriedly. “The wire isn't grounded now.”

“He's taken to cover, I guess,” said Lanson. “I was afraid he would scare, no matter how——” He broke off abruptly. “Wait! What's that!”

The sounder was clicking again; but the sharp, quick tattoo was gone, and in its place, as though indeed it drawled, the sending came in leisurely, deliberate fashion.

The Hawk's pencil resumed its labours—and then, with a queer smile, the Hawk scratched out what he had just written. It was no longer code—it was in exceedingly plain English.

Martin was reading directly from the sounder:

“'Try—that—game—just—once—more—and—the—division—goes—up— in—the—air—and—a—train—or—two—maybe—to—a— place—that—Mister—MacVightie—will—some—day—honour—with— his—presence. That's—quite—plain—isn't—it? If—you—think—this—is—a—bluff—call—it. Now—keep—off—the—wire—or—have—it—cut. Suit—yourselves.'.rdquo;

“Well, of all the infernal nerve!” exploded MacVightie furiously.

“And the worst of it,” said Lanson shortly, “is that he's got us where he wants us!”

Once more the sounder broke into the old quick tattoo. The Hawk was writing steadily again. There was silence now between the three in the office.

A minute, two, three went by—the sounder ceased—the Hawk closed his notebook. Then in its leisurely drawl the sounder broke again; and again Martin read aloud:

“'Pleasant—evening—isn't—it? Ask—MacVightie—if—he—has—seen—anything—of—the—Hawk. Good-night.'.rdquo;

But this time there was only a menacing smile on MacVightie's lips.

“He's west of here, you say?” he shot at Martin. “Yes,” said Martin briefly.

“And that splice of Calhoun's, Lanson? Where was that?”

Lanson, drumming with his fingers on the edge of the operator's table, looked up with a frown.

“Nothing but coincidence,” he said tersely. “Yes, it was west of here—pretty near Selkirk.” He moved toward the door. “There's nothing more we can do here to-night. I'm going back on No. 17. Let's get out on the platform until she shows up.”

The Hawk very carefully replaced his notebook, his flashlight and his pencil in his pockets, and, as MacVightie and the superintendent went out of the door, he retreated softly back to the rear window. The window being up, he quite as noiselessly slipped out over the sill. He debated a moment about the window, and decided that if any significance were attached to the fact that it was found open, MacVightie, for instance, was fully entitled to make the most of the significance! Then, the rattle of a wagon sounding from the direction of the road, the Hawk moved along to the end of the station, and waited.

The wagon, in the light of its own smoky oil lamps, proved to be the town hotel bus. There were evidently other passengers for Selkirk besides himself and the two officials, as several people alighted from the bus. In view of this fact the Hawk calmly lighted a cigarette, though the glow of the match exposed his face only to the blank wall of the station, and walked around to the front platform.

He located MacVightie and Lanson; and, thereafter, at a safe distance, did not lose sight of them. MacVightie's memory for faces would hardly be over-rated if credited with being able to bridge a matter of some twenty-four hours, particularly as MacVightie had evidenced unusual interest in the occupant of the room on the first landing over a certain ill-favoured saloon the night before! The Hawk, therefore, was unostentatiously attentive to MacVightie's movements; so much so that, when No. 17 pulled in and MacVightie and Lanson boarded the chair car at the rear of the train, the Hawk, when No. 17 pulled out, quite logically boarded the smoking car at the forward end.

The Hawk chose the most uncomfortable seat in the car—the rear seat with stiff, upright, unyielding back, that was built against the wash-room—and, settling himself down, produced his notebook and pencil. The water-cooler could be quite confidentially trusted not to peer over his shoulder!

On the second page of the notebook—the first having been devoted to the sketch of Bald Creek Station—-the Hawk, as he had taken it from the sounder, had written this:

“wtaz qxpetlkhu wkmuh hdtlq gvhmmpy hqltvd df rmnluvpo nfkhomovfdh gvkerkmmawrq fljkwte dvsoedtdqqh mgfdoifk rxqkuvwruh gsruwmtdoo ommtlqhvksol foghvklst rvrzqmqxpe mkhurqjkh hvdbfvkdzc mnvohrtpqg hutzklwkj hkdqm mo g v pdlqlfxoq uhgpifthglxg pkhlmfj kwhttwb hv d p q g kdrllu eomosdfnhta shqkjvlyhtg mwdlomruhgegf orwmpqk hvwtzrwk mmrxvddg iqggrqo odusnvrx wmfkriu hkvhuymt hixqljtg wrqpxpeh houwkdmd gwsxws vdexmuooh wtjqlqklmp”

The Hawk tore out a page from the back of the notebook, and set down the letters of the alphabet in a column. Opposite these he painstakingly set down another column of letters. After that the Hawk worked slowly. It was not quite so simple as it looked—not merely the substitution of letters in a different order of rotation. Nor, apparently, from the Hawk's observations as he muttered to himself, were all messages to be deciphered alike—the code appeared to possess within itself an elasticity for variation.

“At four... key letter changed... stroke!” muttered the Hawk. “N-u-m-b... pass three... e-r-t-h... stroke one....”

The Hawk's notebook, closed, was reposing idly on the window ledge and the Hawk was lighting another cigarette, as the conductor came down the aisle. The Hawk presented the return stub of a ticket to Selkirk. The conductor punched it, and passed on—and the Hawk picked up his notebook again.

Again he was interrupted—and again. The water-cooler, after all, was not proving an unmixed blessing. It seemed as though every man in the car were possessed of an inordinate thirst. They were well on toward Selkirk when the Hawk finally completed the deciphering of the message.

It now ran: