_Sturgeon_ put her helm over in the usual way to avoid the explosion area, but turned again on hearing the detonations and had the satisfaction of seeing the U-boat shortly afterwards break surface with her bows up at an ominously high angle. She was by this time near closing _Retriever_, but Lieutenant-Commander Coombs considered her as still his hare. He turned again and raced for her like a greyhound. She tried to submerge, but could not get down quickly enough. Every one of the three destroyers could have rammed her, for as they came up to her in succession they could all see some thirty feet of her bows, with hydrophones and net-cutters, lying almost under them. But there was no need to take the risks of a concussion--this was a plain case for more depth-charges. _Sturgeon_, as she passed over a second time, dropped the remainder of hers. Then came _Retriever_ an instant later, with two more; and she also dropped a Dan buoy, to mark the exact spot for _Thruster_, who was coming across from a greater distance. By the time _Thruster_ arrived, she found the U-boat entirely submerged, but she methodically added her two depth-charges and both of them exploded within five yards of _Retriever’s_ buoy, and probably not more from the submarine, which they followed down to eighty feet.
So far, no one had thought of doubting the success of this very well executed triple attack; and indeed the evidence was both strong and plentiful. The U-boat was clearly seen to have been damaged by the _Sturgeon’s_ first two charges, for she reappeared almost at once and at an unmistakable angle. The six other charges dropped over her were none of them blind shots--_Sturgeon_ and _Retriever_ both saw their target plainly, and _Thruster_ had the Dan buoy to guide her. The Rear-Admiral, in reporting the case, added that he was himself a witness of the attack and was of opinion that the submarine was destroyed. As corroborative evidence, he named the following articles, which were picked up near the spot: 1 wooden ladder, 1 red _kisbie_ lifebuoy, 1 calcium float, and 1 steel buoy with fractured wire pendant attached. The lifebuoy and calcium float were not of British make, and the former was marked with letters and numbers not used in our Service. Finally, the area round the Dan buoy was thick with oil, which came gradually up during the two hours succeeding the chase.