At the same instant a voice boomed out from the fore-peak:

“Something dead ahead, sir!”

And then the next moment a heart-chilling hail from the crow’s nest:

“Ice ahead! A big berg right under our bow!”

Jack leaped from his instruments, a nameless dread clutching at his heart. There had been no impact as yet, but he did not know at what instant there might come a crashing blow that would tear the stout steel plates of the tanker open as if they had been so much cardboard.

For a moment wild panic had him in its cold grasp. Then, heartily ashamed of the cold sweat that had broken out on him and the wild impulse he had had to cry out, he clenched his hands and regained control of himself.

The whole fabric of the ship quivered as the mighty engines flew round in the opposite direction to that in which they had been rotating. At the instant Captain Braceworth’s order had been given it had been obeyed.

For a breath there was killing suspense; and then suddenly there came the shock of an impact. It was not a violent one, but just a grating, jarring shock.

“Great Scott! We’ve struck!” exclaimed Jack, as the next instant there came a second and more violent contact.

He was thrown bodily from his feet. Forward there came a babel of cries.

The ship listed heavily to port and then slowly, like a wounded creature, she righted. Then came a sound of thunder as the masses of ice, dislodged from the berg by the collision, toppled and slid from her fore-decks.

Jack knew that what the skipper had dreaded had come to pass. In spite of ceaseless, sleepless vigilance and the exercise of every caution a man could use, the Ajax had rammed an iceberg.

Above the yells and shouts of the seamen came the captain’s calm, authoritative voice.

His orders rang out like pistol shots. Accustomed to obey, the seamen stopped their panic and fell to their work. The mates were down among them, silencing the more obstreperous in no very gentle manner.

A squad of men came running aft to the boats. For an instant Jack thought that, in their panic, they were about to lower away and make off. But he speedily saw, to his immense relief, that they were in charge of cool-headed little Mr. Brown; they had been sent aft merely to stand by the boats and tackle in case it became necessary to abandon the ship.

Jack jumped to his key. If the ship was sinking, he would show them that he could live up to best wireless traditions.

Out into the black, fog-bound night went thundering and volleying the stricken ship’s appeal for aid. But the boy did not send out the S.O.S.; that could only be done by the captain’s orders. His intent was to inform any ship within his zone of their plight, so that they might stand by to render assistance if it should be necessary.

But no answer came to the wireless appeal that the boy flung broadcast through space. Time and again he tried to summon help, but none answered his call.

The captain himself came aft, leaving things forward to the first officer. The second officer and the carpenters were sounding the ship to discover if her wound were mortal or if she could make port somehow.

Somewhere off in the fog Jack could hear the swells breaking as if on a rocky coast. He knew they were beating against the iceberg that the ship had crashed against!

Jack looked up as the captain entered the wireless room. Never had he admired the man as he did in that instant. Pale, but stern and resolute, Captain Braceworth looked the man of the minute, a fit person to cope with the dire emergency that had befallen them.

“Any ships in our zone, Ready?” he asked calmly.

“No, sir, I’ve been trying to raise some and——”

“Very well. Keep on. If you get into communication, report to me at once.”

“Yes, sir. Are—are we badly hurt, sir?”

“It is impossible to say. We are trying to find out now. I need not tell you it is your duty to stay at that key till the last boat leaves the ship.”

“You need not tell me that, sir,” said Jack, flushing proudly. “I’d go down with her if it would do any good.”

The captain looked oddly at the boy a moment and then slapped him hard upon the back.

“You’ve the right stuff in you, Ready,” he said and hurried off again.

The ship was still slowly backing. Presently Jack heard the mate’s big voice booming out from forward.

“She’s flooded to the bow bulkhead, sir, but so far as I can see, there’s no immediate danger. When daylight comes, we may be able to patch her up.”

This was hopeful news, and a cheer arose from the men as they heard it. But mingled with the cheer came another sound—a muffled roar like that of wild animals or of an enraged mob.

What it meant flashed across Jack in a jiffy.

The firemen, The Black Squad, as they were called! They had mutinied against being penned in the fire-room on a sinking ship and were rushing to the deck.

Without knowing just what he was doing, the boy took his revolver out of the drawer where he kept it and rushed outside. The first thing he saw under the glow of the lights was the figure of Raynor.

The young engineer’s head was bleeding from a cut and in his hand he had a big spanner. Pressing upward behind him as he backed out of the fire-room companionway were the Black Squad, wild with panic. In their hands they carried slice-bars, shovels, any weapon that came handy.

“Stand back, I tell you,” commanded Raynor, as Jack approached him.

“Stand back nothing,” bellowed a giant of a stoker. “Think we’re going to the bottom on this rotten hooker? Stand back, yourself. Come on, boys! The boats! We’ll get away while there’s time.”

“You’ll stay plumb where you are or be drilled as full of holes as porous plasters!”

It was little Mr. Brown who spoke. Almost before he knew it, Jack was at the doughty little officer’s side and stood with Raynor and Mr. Brown facing that howling mob from the black regions below.