The twenty-one-inch gleaming steel cylinders, set to the minimum depth, were already in the tubes. The torpedo gunner and his mate were grimly alert, grasping the ball-ended levers that were to liberate the charge of compressed air.
Slowly, ever so slowly, the British submarine swung to starboard, until her skipper knew that the fixed tubes were pointed straight towards their quarry.
"Ready—fire starboard!"
With a hiss as the air, hitherto compressed to two hundred pounds to the square inch, rushed from its compression chamber, the deadly missile sped on its way. Beyond the swish of the inrushing water that was automatically admitted to compensate the loss of weight caused by the speeding torpedo, not a sound broke the deadly stillness pervaded the interior of the submarine.
Four seconds later a dull roar betokened the fact that one torpedo was sufficient for the work of destruction.
"Blow main ballast tank," ordered the skipper.
No need for caution now. The victor could appear on the surface with impunity. She rose almost vertically, for she had almost lost way. With the water pouring in cascades from her steel deck she flung herself free from the encircling embrace of the sea, and curtsied to the morning air.
Hatches were quickly opened, and officers and men rushed on deck to see with their own eyes the result of their successful work.
Already the unterseeboot had vanished for the last time. An ever-widening circle of sullen water heavily tinged with oil, and surmounted by a cloud of pungent smoke that was slowly dispersing in the calm air, marked the spot where the luckless submarine had plunged to the bottom.
The canvas boat was still afloat. Some distance from the point of impact of the torpedo she had withstood the suction of the sinking vessel, and was now bobbing sluggishly to the undulations caused by the rebound of the disturbed water from the sides of the creek. The two German seamen, staring with wide-open eyes as if terrified by the appalling nature of the catastrophe, were crouching in the Berthon, while through the oil-spread water a third man was laboriously swimming towards her.