The submarine Brown was in was acting as "target" for other boats which were practising attacks on her as training for actual war attacks on U-boats at sea. The exercising area was just off Harwich, and the "target" was running a straight course along it, looking out for the periscope of the attacker. Suddenly the periscope appeared--50 yards on the bow and travelling fast; a collision was inevitable. The attacker's conning-tower was smashed, and she sank at once with all hands. The captain of the "target" was on the bridge, and receiving a report that his own boat was sinking fast, he called all hands on deck. Petty Officer Brown did not apparently hear the order, and with two other men (a stoker and engine-room artificer) went down with the boat. The conning-tower lid being open as she sank, the stoker and artificer who were in the midship compartment waited a few seconds in a pocket of air near the conning-tower ladder, and then dived for it, swimming through the boat till the gleam of brighter water showed overhead, then rising up through sixty-five feet till they gained the surface. Brown had taken shelter in the engine-room, closing the door after him. His own account of the incident is quite clear, though perhaps a little technical. ... "Something was heard to come in contact with the bottom of the boat forward, twice in quick succession. Immediately after the engine-room telegraph rang to 'out-clutches.' I took out the port clutch and closed the muffler valve--then it was reported that the ship was making water. I proceeded forward to ascertain the position of the leak, and came to the conclusion she was holed down low. My first impulse was to close the lower door of the conning-tower. At this point the chief engine-room artificer inquired if all hands were out of the engine-room. I replied I would find out. On going aft I found one man coming forward, and I ordered him to put his life-belt on, keep his head, and wait his turn at the conning-tower hatch. Finding there was nobody else aft, I came forward and put on a life-belt and closed the valve on the air trunk through the engine-room bulkhead--then water began to come down through the conning-tower hatch and the boat took a dip forward...." From the collision to this point was actually about 90 seconds. Brown leaves the impression in one's mind that he spent part of this time "tidying up" and generally giving a final polish to his department before leaving (perhaps he did):--