Minel Axing

MINEL AXING Mines are laid by vessels specially fitted to carry them. In surface vessels the mines rest on their sinkers which have wheels at the bottom running on rails laid on the decks in a fore and aft direction. Means are provided for hauling the mines along these rails until they enter the mine traps placed in ports cut in the stern of the ship. The traps hold the mine in position ready for letting go. When the trap is opened the mine sinker runs down a short curved piece of the rails and drops into the water. In mine laying submarines the mines are carried in tubes or shoots formed in the hull, from which they can be released one at a time.

British Minelaying Resources.

At the outbreak of hostili ties in 1914 the British Navy possessed seven old cruisers (Latona class) fitted as minelayers. These had a speed of only 14 knots. Shortly afterwards four merchant ships were added ; and in the second part of the War a considerable number of submarine mine layers and fast destroyers were used.

German Minelaying Resources.

At the outbreak of war the Germans had available 3 men-of-war and nine auxiliary ves sels fitted as minelayers. Two of the men-of-war "Nautilus" and "Albatross," were 20 knot vessels and each carried 200 mines. During the War four more auxiliaries were fitted including the raiders "Mowe" and "Wolf." In 1915 the first of the submarine minelayers started work. In June 1915 a small type, termed U.C. boats, working from Zeebrugge, with Bruges as a mine-depot, com menced laying batches of 12 mines held in vertical shoots, at first between Dover and Harwich, and later over a wider area. During 1915, 54 cargoes (648 mines) were laid in this manner. The effect was a serious increase in British losses by mine, which comprised 5 supply ships, 1 hospital ship, 2 Trinity House vessels, 34 steam ers, 19 fishing boats and 15 minesweepers, also 24 neutrals, a total of 1 oo vessels. The number of German submarine minelay ers increased in 1916, and there were larger boats operating over a still wider area. These carried 18 mines. As further construc tion improved, the number of mines carried rose to 24, and in 1917, to 36. The larger boats worked from the Elbe, and the smaller from Flanders.

Elements of Mining Warfare.

Three factors are necessary for successful mining warfare—the strategic function, the opera tion of laying the mines and the technical efficiency of the mine itself. The first of these factors is woven into the main strategy

of a naval war. The stronger fleet, in its anxiety to seek out and destroy its enemy, desires a clear sea; and, to obtain this, must insure that such a means of attrition as the mine is reduced to the utmost. On the other hand, the weaker fleet will use the mine profusely in an endeavour, by attrition, to reach an equality or superiority of force : and it will also use this weapon against mer chant ships, particularly when they belong to a belligerent de pendent on its carriage of foodstuff from overseas. This was the initial stage of naval strategy in the World War; and to some extent it explains the pre-war application of the Germans to min ing and the comparative neglect of the subject by Great Britain. The second factor is the operation of laying the mines. To be successful, this must be governed by the element of surprise, and be expeditiously performed ; it requires for its purpose a ship of high speed, or one which, by disguise or subterfuge, can carry out the work unmolested.

The third factor is purely one of technique. No type of mine that does not meet the following requirements is efficient. It must be safe until it is laid. When laid, it must take up and maintain its required depth, throughout all kinds of weather, for an appre ciable length of time. It must be immune from mechanical failure when required to function. In the interest of both belligerents and neutrals, it must automatically render itself safe should it break from its moorings. Considerable importance attaches to the design of a minefield. A simple straight line of mines is easily and quickly laid, but presents little difficulty to the minesweepers once it is located. Lines of mines laid in zigzags, particularly when spaces of water are left clear, present the greatest difficulty to removal. On the other hand, such patterns will necessarily cover a larger sheet of water, and will require very accurate plotting if, subsequently, the vicinity of the mined area is to be approached by the sea forces of the minelayer. An existing apparatus termed "taut wire measuring gear" proved a great aid to accuracy in positioning a minefield.