At 8 o’clock, then, on the finest summer morning of the year, Commander Cooper was making his passage at normal surface speed, when the horizon on his starboard bow began to be delicately shaded by faint pencilled lines. Ten minutes more and a number of ships were visible, two points on the bow, and five to six miles away. They were immediately in the sun, and blurred by the haze, so that it was impossible to detect their nationality. They might be our own squadron, coming back unexpectedly early, or more likely a hostile force running from them. The only thing certain was that they had sighted the submarine and were bent on her destruction, for they were all bows on, bearing down upon her at high speed--destroyers and cruisers--throwing up clouds of dense black smoke. Commander Cooper was in no indecent hurry, but he knew what he had to do. He must get down, or be put down. Moreover, he must get well down; for the water was very clear, and the sea flat calm, without a ripple. After a last look at the charging squadron he dived to ninety feet, changing his course to 185°. His troubles began at once: the helm was reported jammed--it was amidships. He sent the first-lieutenant to inspect, the report was that the gear was all correct--the jamming seemed to be due to the tightening of the rudder-post gland, either from external pressure, or from some distortion of the after compartment of the ship. In any case, nothing could be done for the moment, and there were plenty of distractions coming. At 8.37 the sound of propellers was recorded on the hydrophone--the destroyers were passing from port to starboard overhead, like hounds abreast trying to pick up a scent. One of them, must have thought she had hit it off, for a tremendous explosion shook the submarine--a depth-charge had been dropped not far behind her, shaking her stern violently. In her steering flat, the first-lieutenant and his men were lifted bodily off their feet. The commander continued his dive, and to his great comfort took bottom at 125 feet on the gauge. Within three minutes of the first explosion, a second one followed. It was equally violent, and to Commander Cooper appeared even louder; but he told himself that this effect was probably due to the relative position of the bomb, which had apparently detonated in a line with the conning-tower. As he was himself in the control-room, in the centre of the ship, the explosion would naturally sound louder, being on the starboard beam instead of aft.