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.
Two submarines had answered his signal, instead of one, and the last had crept up to attack him while he was sinking her consort.
The steamer, however, answered her helm, slowly, but enough. The swift white streak drove past her stern with a few feet to spare, and she began to shake as her engines quickened.
"Port!" Rankine shouted in a harsh voice. "Steady that!"
A flash blazed out of the darkness, a panel of the wheelhouse was shattered, and the canvas bridge-screen fell apart in rags; but Rankine had seen a long, dark shape on the water close ahead. It might vanish in a moment, before his guns could be swung and trained. Indeed, he doubted if the submarine were within their field of fire, and he meant to use a surer means. One end of the black hull tilted up and the other began to sink. His enemy was going under. But would she be quick enough? The steamer's sharp steel stem was only a dozen yards away now.