1.30 P.M. _Conyngham_ to _Achates_: Aubrietia to all men-of-war and Land's End. Chasing submarine on the surface 49.30 N 6.8 W, course south-west by south. Waiting to get into range. He is going faster than I can. 2.00 P.M. _Aubrietia_ to all men-of-war. Submarine submerged 49.20 N 6.12 W. Still searching. The fact that nothing more was seen of that submarine may possibly detract from the thrill of the experience, but in describing the operations of this convoy I am not attempting to tell a story of wild adventure, but merely to set forth what happened ninety-nine out of a hundred times. What made destroyer work so exasperating was that, in the vast majority of cases, the option of fighting or not fighting lay with the submarine. Had the submarine decided to approach and attack the convoy, the chances would have been more than even that it would have been destroyed. In accordance with its usual practice, however, it chose to submerge, and that decision ended the affair for the moment. This was the way in which merchant ships were protected. At the time this submarine was sighted it was headed directly for this splendid aggregation of cargo vessels; had not the _Aubrietia_ discovered it and had not one of the American destroyers started in pursuit, the U-boat would have made an attack and possibly would have sent one or more ships to the bottom. The chief business of the escorting ships, all through the war, was this unspectacular one of chasing the submarines away; and for every under-water vessel actually destroyed there were hundreds of experiences such as the one which I have just described. The rest of this trip was uneventful. Two American destroyers escorted H.M.S. _Cumberland_--the ocean escort which had accompanied the convoy from Sydney--to Devonport; the rest of the American escort took its quota of merchantmen into Brest, and from that point sailed back to Queenstown, whence, after three or four days in port, it went out with another convoy. This was the routine which was repeated until the end of the war. The "O Q 17" and the "H S 14" form an illustration of convoys which made their trips successfully. Yet these same destroyers had another experience which pictures other phases of the convoy system.