month. It was off this coast the UC44 was working in summer, to be blown up on Aug. 4 by one of her own old mines off Waterford. Out of 380 mines laid by the High Sea Fleet minelayers and 36 by the Flanders Flotilla in this area, 332 were accounted for with the loss of nine steamers and nine minesweepers. Some 26 mines were also laid off the west coast of Ireland, but did no damage, except in one case where the villagers mistook one which had drifted ashore for a new sort of cask of liquor and tried to open it, with the loss of nine lives. Off the west coast of Scotland, out of 130 mines cleverly laid by the U80 off Mull, Stornoway, Coll, Skye and Harris, 76 were accounted for.
The year 1917 closed with a total of 3,989 enemy moored mines swept up in home waters, at a cost of 170 Allied and neutral merchant ships sunk and 28 damaged. The whole outlook was more hopeful, for while enemy minelaying as compared with 1916 had more than doubled, the number of ships sunk had increased only from 161 to 170.
Abroad the voyage of the German raider “Wolf” (Capt. Karl Nerger) had given minesweepers work in many an unexpected spot. She left Germany on Nov. 30 1916, slipped through the blockade line and got safely out to sea. She was a ship which registered 6,000 tons and carried 458 mines besides an armament of four 6-in. guns. Her voyage lasted 15 months. Rounding Cape of Good Hope, she cruised in the Indian Ocean, then proceeded south of Australia to New Zealand and Fiji, and, returning by New Guinea, the Dutch East Indies and the Cape, reached Germany safely in March 1918. Her mines were found all over the globe. Her first group of 25 was laid off Dassen I. (Capetown) and her second of 29 on Jan. 18 off Cape Agulhas (S. Africa). The former were swept up by four whaling steamers commissioned for the purpose. In the Agulfyas field two vessels were lost and only seven mines swept up in 1917. On Feb. 15 1917 39 mines were laid off Colombo and 19 off Cape Comorin (Ceylon). One of her prizes, the “Turritella” (renamed “Iltis”), dropped some 25 off Aden, and a large group of 68 mines off Bombay was laid by one of the two ships. The Colombo group was swept up by six trawlers, with the loss of two large ships. The Aden group was dealt with by small harbour tugs manned by Somalis within two months of its location and with the loss of one ship. The large group off Bombay was attacked by local vessels manned by British officers and Lascars, and 51 of its mines were swept up by June with the loss of five steamers.
The “Wolf's” next mining exploit was in Australian seas, where she laid 14 mines off Gabo I., the S.E. point of Australia, between Melbourne and Sydney, with the loss of one steamer; this was followed by a cruise to New Zealand, where 15 mines were laid in Cook Strait, between North and South Is., and 17 off Three Kings I. in the extreme north. These were all dealt with by Australian and New Zealand naval forces. Her last effort consisted of no mines laid N.W. of the Andaman Is. (Indian Ocean) on Sept. 4 1917, which were not located in that year. Her mines were responsible for the loss of some 15 ships, and it was not till Jan. 15 1918 that definite news of her movements was received at the Admiralty.
But by 1918 the effect of improved British methods was telling heavily on the enemy. The toll of German losses and the difficulty of replacing trained personnel were seriously affecting her minelaying, and the total number of Allied and neutral merchant vessels lost by German mining fell to 27. Closer cooperation between the intelligence and minesweeping divisions, the rapid distribution of intelligence, the firmer control of shipping and the use of the “otter”—all contributed to this very marked decrease.
The Germans now began to concentrate their minelaying efforts in three special directions—the maintenance of a minefield off the Dutch coast directed against the Dutch convoys, the laying of a large semicircular barrage about 45 m. from the Forth aimed at the Grand Fleet, and attacks on the route of the Scandinavian convoys. The first took the form of a field laid off Ymuiden and the Maas containing some 400 mines, which was extended by the labours of two U-boat minelayers working continuously in this area. It was responsible for the loss of five destroyers and remained a source of grave danger, for minesweepers working there were exposed to sudden attacks from the Flanders coast. The barrage off the Forth met with no success. The mines were rapidly located (in two cases by paravanes) and swept up almost as soon as they were laid. The attacks on the Scandinavian convoy routes were equally unsuccessful. Some 90 mines were swept up with the loss of only one steamer.
In the Harwich area 265 mines were laid, of which 213 were accounted for, with the loss of five steamers and four minesweepers. The discovery of a mine off Walney I. (Lancashire) on March 8 led to special vigilance in that area, and when mines were laid in the Mersey the next night, a unit of paddlers, held in readiness for the emergency, was at work at once clearing the fairway and opened the port to traffic within 48 hours.
The introduction of a French pattern of scissors to cut through the mooring-wire of a mine was one of the developments of the later years of the war, though the difficulty of minesweeping did not lie in cutting the mine's mooring-wire when found but in finding the mine in a trackless expanse of water under all sorts of conditions of tide and weather.
A very considerable amount of minesweeping work in 1918 arose out of British minelaying. The mines in a portion of the northern barrage were laid too shallow and had to be swept up in the approaches to the Orkneys. The same fault was found in Dover barrage, where some 280 mines had to be swept up and a great increase in drifting mines was experienced. The Channel still continued to be visited occasionally, and in the Portsmouth area 44 mines were accounted for with the loss of two merchant ships and two minesweepers.
In the Mediterranean, the enemy had devised a mooring system for tideless waters which permitted of mines being laid in too fathoms, but the clear blue water lent itself to aircraft reconnaissance which, in concert with light-draught motor-vessels, made location easy. Thirty mines were destroyed off Malta during the year 1918 with the loss of one steamer. The minesweepers were largely manned by Maltese reservemen who displayed a gallant spirit and seamanlike competency in their work.
Long before the Armistice, British minesweeping had gained the mastery over German minelaying, and as soon as Ostend and Zeebrugge fell into British hands, the protective minefields round them were swept up. When the hour of the Armistice struck, a minesweeping force was waiting at the gate of the Dardanelles, and within 24 hours 600 British and enemy mines had been removed from the entrance and a passage cleared for the fleet to Constantinople.
A few words may be said as to the method of distributing information of mines. This was sent out in what were called, from their index letter, “Q” messages, which were priority messages going to all shore stations by land wire and to all forces at sea by Cleethorpes wireless station at regular intervals. Immediately a mine was discovered or swept up, the spot was buoyed and local traffic at once diverted or, if the mine was in the war channel, held up. As soon as tidal conditions permitted, the area was swept. The text of a “Q” message was sent by the senior officer to the Admiralty, and, after being checked by the Minesweeping Division, was at once sent out to all ships and stations, the average time from the discovery of a mine to the issue of information to ships at sea being about 114 hours.
The growth of the minesweeping service and the greatness of its task, performed largely by British fishermen, may be gathered from the following figures. At the Armistice the minesweeping forces in British home waters comprised no fast sweepers organized in 20 minesweeping flotillas, 52 hired paddlers, 412 trawlers, 142 drifters and 10 “Dance” minesweepers—a total of 726 vessels. The number of mines destroyed at home and abroad by British vessels during the war amounted to 23,873 (moored, 11,487; drifting, 12,386). The ships sunk and damaged by mines numbered 595. The number of minesweepers sunk or damaged was 214, in the following areas: Fleetsweepers, 5; Lerwick, 1; Kirkwall, 3; Cromarty, 3; Peterhead, 2; Granton, 9; Tyne, 6; Grimsby, 15; Lowestoft, 48; Harwich, 24; Nore, 15; Dover, 33; Portsmouth, 13; Portland, I; Plymouth, 3; Falmouth, 2; Bristol Channel, 6; Queenstown, 7; Belfast, 6; Clyde, 2; Stornoway, I; abroad, 9.
Minelaying.—Minelaying played a very important part in the later years of the World War, but to form a true estimate of its value a careful distinction must be drawn between three factors essential to its success—its strategical use and function, the
