"Are you joking, Mr. Reade?"

"No, sir; I am not. Dynamite must have been used. Hazelton and I heard the noise of the blast, but of course we got out there too late to catch any miscreant at the job."

Evarts, at first, was inclined to regard the news with mild disbelief, but he soon realized that something must have happened very nearly as the young chief engineer had described.

"Well, what are you standing there for?" Tom demanded, impatiently. "Are you going to wait for daylight? Get the four men out---all Americans, mind you. _Hustle_, man!"

Evarts started away; toward the camp over to the left of them. As he did so Tom darted in another direction. Two minutes later Tom was back, piloting by one arm a man who was still engaged in rubbing the sleep out of his eyes. This was Conlon, engineer of the motor boat, "Morton."

"Where's Evarts?" Reade queried, impatiently. "Oh, Evarts! Where are you, and what are you doing?"

"Trying to get four men awake," bawled back the voice of the foreman, from the distance. "As soon as I get one man on his feet the other three have sunk back to sleep."

"Wait until I get over there then!" called Tom, striding forward. "Come along, Conlon! Don't you lag on me."

"There! Do you fellows reckon you want Mr. Reade to b.u.mp in here and shake you out?" sounded the warning voice of Evarts.

As Tom and the motor boat's engine tender reached the little, box-like shack from which Evarts's tones proceeded, four men, seated on the floor, were seen to be lacing their shoes by the dim light of a lantern.

"A nice lot you are!" called Tom crisply. "How many hours does it take you to get awake when you're called in the middle of the night?"

"This overtime warn't in the agreement," sleepily retorted one of the men.

"You're wrong there," Reade informed him, vehemently. "Overtime _is_ in the agreement for every man in this camp when it's wanted of him---from the chief engineer all along the line. Now, you men oblige me by hustling.

I don't want to wait more than sixty seconds for the last man of you."

"I've a good mind to crawl back into my bunk," growled another of the men.

"All right," retorted Tom Reade, with suspicious cheerfulness. "Try it and see what kind of fireworks I carry concealed on my person. Or, just lag a little bit on me, and you'll see the same thing. Men, do you realize that there's foul play afoot out on the retaining wall? We've got to go out there in time to stop anything more happening. Now, you've got your shoes on; grab the rest of your clothing and hustle it on as we make for the beach. Come along!"

Tom fairly got behind the men and pushed them outside. They would have liked to complain, but they didn't. Some of them were larger and heavier than the chief engineer, but they knew quite well that, at sign of any trifling mutiny to-night, Reade would thrash them all.

"If any one is trying to blow up the wall, Mr. Reade, it's all your fault, anyway," ventured Evarts, as the little party started at a brisk walk for the beach. "When you've got a mixed crowd of men working for you, you shouldn't interfere too much with their amus.e.m.e.nts. Yet you would have the gamblers run out of camp just when our boys were getting ready to have some pleasant evenings."

"I'll run out any one else who attempts to bring disorderly doings into this camp," Tom retorted quietly.

"Then there'll be some more of your seawalls blown up," Evarts warned him gloomily.

"If such a thing happens again there'll be some men hurt, and some others breaking into prison," Tom answered with spirit. "Any evildoers that try to set themselves up in business around here will soon wish they had kept away---that's all."

"It's a bad business," insisted Evarts, wagging his head. "When you have a mixed crowd of workmen---"

"I think you've said that before," Tom broke in coolly. "To-night we're in too much of a hurry to listen to the same thing twice. Come on, men.

You can go a little faster than a walk. Jog a bit---I'll show you how."

"This is pretty hard on men in the middle of the night," hinted Evarts, after the jogging had gone on for a full minute. "It ain't right to-----"

"Stop it, Evarts!" Tom cut in crisply. "I don't mind a little grumbling at the right time, and I often do a bit myself, but not when I'm as rushed as I am to-night. There's the dock ahead, men---a little faster spurt now!"

Tom urged his men along to the dock. With no loss of time they tumbled aboard the "Morton," a broad, somewhat shallow, forty-foot motor boat of open construction.

"Get up and take the wheel, Evarts," Tom. directed. "Get at work on your spark, Conlon, and I'll throw the drive-wheel over for you. Some of you men cast, off!"

In a very short time the "Morton" was going "put-put-put" away from the dock.

Tom, after seeing that everything was moving satisfactorily, turned around to look at the four men huddled astern.

"Don't any of you go to sleep," he urged. "A good part of our success depends on how well you all keep awake and use your eyes and ears."

That said, Tom Reade hastened forward, stationing himself close to Evarts, who had the steering wheel.

Some of the men astern began to talk.

"Silence, if you please," Tom called softly. "Don't talk except on matters of business. We want to be able to use our ears. Conlon, make your engine a little less noisy if you can."

Now Reade had leisure to wonder how matters had gone with Harry Hazelton.

"Of course that threatening figure Harry saw behind him was an imaginary one," Tom said to himself, but he felt uneasy nevertheless.

A few moments later Reade clutched at one of Evarts's arms.

"Did you hear that, man?" the young engineer demanded.

"Hear what?" Evarts wanted to know.

"It sounded like a yell out there yonder," Tom rejoined.

"Didn't hear it, Mr. Reade."

"There it goes again!" cried Tom, leaping up. "Some one is calling my name. It must be Harry Hazelton, and he must want help. Conlon, slam it to that engine of yours!"

CHAPTER III

VANISHING INTO THIN AIR

Left by himself Harry had stood, at first, motionless, or nearly so. He strained his hearing in trying to detect any unusual sound of the night, since it was so dark that vision would not aid him much.

There was nothing, however, but the mournful sighing of the wind and the lapping of the waves. It seemed to Hazelton that the wind was growing gradually more brisk and the waves larger, but he was not sure of that until the water commenced splashing across his shoes. The footway on the masonry became more slippery in consequence.

"With these rocks well wet down I wouldn't care much about having to run back to the land," muttered Harry, dryly. "However, I won't have to go back on my own feet. Tom will have the boat out here, and undoubtedly he will plan to have us both taken back to sh.o.r.e after we get through cruising around here. We should have brought the boat out in the first place."

A night bird screamed, then flapped its wings close to Harry's face in its flight past him. The young engineer saw the moving wings for an instant; then they vanished into the black beyond.

Farther out some other kind of bird screamed. The whole situation was a weird one, but Harry was no coward, though a less courageous youth would have found the situation hard on his nerves.