When this was added to their other troubles the submarines thought twice before risking an attack on a convoy of ships guarded by cruisers, as well as by destroyers ahead and on both sides, zig-zagging about on the hunt for submarines, much as a good sporting dog quarters likely ground for game. A "mothering" cruiser would keep station astern, where she could have her weather eye on every one. In narrow waters like the English Channel there would also be an airship overhead, a little in advance, with seaplanes on the flanks. These aircraft could spot a submarine almost a hundred feet down in fair weather, just as seabirds spot fish. If a submarine did show up, it was kept in sight till the destroyers charged near enough to ram, shell, or torpedo it on the surface, or sea-quake it to death with a depth bomb if submerged. Three hundred and seven ships brought wheat from different parts of America to Britain, France, and Italy under special convoy in the summer of 1918, and only one was lost. "Q" ships, those ships of mystery and such strange romance as former navies never dreamt of, were meant to lure the German devils to their doom. One Q ship was a dirty old collier so well disguised as a common tramp (steamer belonging to no regular line) that she completely took in a British cruiser, whose boarding officer was intensely surprised to find her skipper was one of his own former shipmates. After five months of thrashing to and fro in the wintry North Atlantic a torpedo sped across her bows and she knew her chance had come. Instantly her alarm signals, quietly given, brought all hands to action stations, some in deck-houses, others in hen-coops, but each with his finger on the trigger or his hand on a ready spare shell. Presently the submarine broke surface and fired a shot across the Q ship's bow. On this the well-trained crew ran about in panic, while the captain screeched at them and waved his arms about like mad. Then the submarine came up within three cables (ten to the nautical mile of 2000 yards); whereupon the captain blew his whistle, just as Drake did long ago, the Navy's White Ensign fluttered up to the masthead, the hen-coops and deck-houses fell flat, and a hurricane of shells and Maxim bullets knocked the "sub" out in three minutes' firing.