An hour later, Rankine pressed a button and the engines stopped. The clang of a steamer's bridge-telegraph can be heard some distance off, but Rankine had substituted an electric signal. Having undertaken a dangerous piece of work, he had carefully made his plans so that he need not announce his movements to the enemy. Two guns had been put on board the vessel, but as it was thought advisable to conceal them, and the deckhouse and the masts were in the way, their fire commanded only a limited strip of horizon.
Rankine searched the water with his night-glasses.
The coast was out of sight, mist drifted across the sea, and the night was dark. On the whole, this was an advantage, for his antagonist was expecting a trawler, and the darkness would prevent him from noticing the vessel's size and rig until they were close together. There was some swell, though the surface of the water was smooth, and the vessel rolled languidly. A feather of steam eddied about her funnel, and there was a soft splashing as her slanted side sank into the sea. No gleam of light pierced the darkness; everything was still; and Rankine stood waiting eagerly.
Presently he gave an order and one of the prisoners was brought to the bridge; then the steamer slowly moved ahead while a petty officer, standing behind a canvas wind-screen, alternately held up and lowered red and green pyrotechnic flares. The streams of colored light showed shadowy figures waiting motionless at their stations and drove a radiant track across the water. Then they died away and men whose eyes had been held by the glitter felt relief. Now they could see about the ship, and they knew watchfulness was needed.
For five minutes nothing happened, and Rankine, conscious of keen tension, began to wonder whether he should signal again. It was possible that he had overshot or fallen short of his distance. Then a sharp hail came from a lookout and he saw the sea break not far ahead. A confused white ripple spread away from something that moved amidst it, and drew out in a long, wavering line. A lantern flashed between regular intervals of darkness, and presently a low, black object grew out of the advancing foam. Rankine pressed the button and the throb of engines slackened; then he gave an order to his prisoner.
The man hailed in German; the submarine swerved and slowed; and the two vessels drew abreast, perhaps fifty yards apart, while Rankine's quarter boat swung out from the davits.
"Tell them to jump into the water and I'll pick them up!" he ordered the prisoner.
As the man called out, a dazzling beam from the searchlight played upon the submarine's hull and her wet steel skin glittered like silver. The next moment there was another flash, streaked with a vein of red; and a cloud of thin, acrid smoke whirled up. The steamer quivered with the heavy concussion; the submarine reeled and listed over. Indistinct figures plunged into the foam that lapped about her side; and then the bright beam showed an empty stretch of seething water: Rankine was watching his boat, which moved into the lighted track on her work of rescue, when a lookout shouted a hoarse warning.
Swinging round, Rankine saw a feathery streak of foam on the opposite side of the vessel. It was heading toward her at tremendous speed, and he knew the wash of a torpedo.
"Starboard, hard!" he called to the helmsman; and set his lips as he pressed the button for full speed.