Before Captain Restronguet could say another word a hoarse order came from the fore bridge, followed by a shrill bugle-call for "General Quarters" and the long-drawn notes of the bo's'un's-mates' whistles.

"What's that?" demanded Captain Restronguet.

"'Clear for action'--a test order perhaps," replied Hythe. "See how those fellows get to work."

Up the companion-ladders officers hurriedly appeared, still fumbling with the buckles of their sword-belts. From for'ard tumbled a swarm of hefty bluejackets, who, invading the sacred precincts of the quarter-deck, began to unship stanchions, davits, ventilating-cowls, and other impedimenta; steel covers were lowered over skylights and companion-hatchways. The securing bolts of the after nine-point-two gun turrets were cast loose, and the long muzzle swung round, causing Captain Restronguet to hurriedly duck his head. In five minutes the quarter-deck of the "Topaze" was deserted, as were the other exposed parts of the ship, every man being at his station behind the armoured portions of the vessel.

Another bugle-call.

"As you were," exclaimed Hythe. "Suppose we go up on the after-bridge. They are exercising. Perhaps the next evolution will be 'Out collision mats.'"

"Hope they won't have to do it in real earnest," remarked his companion as the two men ascended to their coign of vantage.

Once more the bo's'un's-mates' whistles sounded while the bo's'un shouted in stentorian tones "Out nets." The cry was repeated in half a dozen different parts of the ship, and the hither-to deserted decks became a scene of disorder and chaos: at least that's what it seemed to Captain Restronguet, who was for the time being a stranger in a strange land.

Instinctively Hythe pulled out his watch, which once more had stedfastly resisted the assaults of the sea water. Captain Restronguet, gripping the rail, leant over and watched the scene of activity upon the moon-lit deck. Over the side of the gently-rolling craft active seamen slid down upon the apparently insecure net-shelves, and by a series of gymnastic feats succeeded in rolling ten tons of close-meshed steel netting over the side, to the accompaniment of shouts of "Look alive there!" from their officers. Hardly had the last man regained the deck ere the motor capstans of the fo'c'sle began to clank. Seamen armed with spars thrust at the ends of the torpedo booms to give the motor-worked wire rope a chance; then slowly yet surely the twenty hollow steel booms were swung outwards till the "Topaze" was encircled with a "crinoline" of nets at sufficient distance from the ship to stop a deadly torpedo. Back doubled the men to their stations for action.

The sub glanced at his watch. The evolution had taken only forty-five seconds.