The fact that during the second quarter of 1918 the world's output of tonnage overtook the world's losses was another satisfactory feature. The output for 1917 and 1918 is shown in the following table: United Dominions, Kingdom Allied and Total for Output. Neutral World. Countries. 1917 1st quarter 246,239 340,807 587,046 2nd quarter 249,331 435,717 685,048 3rd quarter 248,283 426,778 675,061 4th quarter 419,621 571,010 990,631 1918 1st quarter 320,280 550,037 870,317 2nd quarter 442,966 800,308 1,243,274 3rd quarter 411,395 972,735 1,384,130 4th quarter, Oct. only 136,100 375,000 511,100 It will be noticed that by the last quarter of 1918 the output of shipping in the United Kingdom alone had overtaken the losses of British shipping. It is not possible to give exact information as to the particular means by which the various German submarines were disposed of, but it is believed that of the 186 vessels mentioned as having been lost by the Germans at least thirty-five fell victims to the depth charge, large orders for which had been placed by the Admiralty in 1917, and it is probably safe to credit mines, of which there was a large and rapidly increasing output throughout 1917, with the same number--thirty-five--a small proportion of these losses being due to the mines in the North Sea Barrage. Our own submarines accounted for some nineteen. Our destroyers and patrol craft of all natures sank at least twenty by means of gunfire or the ram, and some four or five more by the use of towed sweeps of various natures. Our decoy ships sank about twelve; four German submarines are known to have been sunk by being rammed by men-of-war other than destroyers, four by merchant ships, and about ten by means of our nets. It is fairly certain that at least seven were accounted for by aerial attack. Six were interned, some as the result of injury after action with our vessels. The total thus accounted for is 156. It was always difficult to obtain exact information of the fate of submarines, particularly in such cases as mine attack, and the figures, therefore, do not cover the whole of the German losses which we estimated at 185. CHAPTER X "PRODUCTION" AT THE ADMIRALTY DURING 1917