The destroyers of the River class, begun in 1903 and completed in 1906, had displacements varying from 540 to 590 tons, but the speed of all of them was about 25½ knots. These were followed by the coastal destroyers, designed, as their name indicates, to operate as destroyers along the coast against any hostile torpedo boats, but now classed as torpedo boats. In the latter capacity their guaranteed speed of 26 to 27 knots would stand them in good stead, but as destroyers they were soon outclassed. Some of them were provided with turbines. [Illustration: H.M. TORPEDO BOAT DESTROYER “SWIFT.” OIL FUEL. _Photograph by Stephen Cribb, Southsea._] [Illustration: H.M.S. “WEAR.” _Photograph supplied by Palmer Shipbuilding Co., Ltd._] The announcement that the Admiralty favoured a speed of 33 knots evoked a chorus of disapproval. The Admiralty was supposed to have become obsessed by a craze for speed, to which everything must be sacrificed. All the old objections which had done duty at every increase of speed for years, and had been proved to be ill-founded, were revived, brought up to date, and launched against the Admiralty proposals. Again it was contended that a vessel travelling at that speed must inevitably founder if she should unfortunately bury her nose in a wave, and that the violent alternation of stresses as she travelled in a rough sea must cause her to break her back or buckle her decks without more ado. But the _Mohawk_, in 1907, came and conquered, much to the delight of everyone except those whose prophecies, as usual, were upset, and not only attained a speed of 34½ knots, but accomplished it in fairly rough weather in the wintry month of November of that year, and proved her soundness of construction and the possession of excellent sea-going qualities. An objection, which at first was supposed to be serious, was that to attain such a high speed her consumption of fuel would be so great that her radius of action would be greatly restricted. The contract under which the _Mohawk_ was built by White, at Cowes, contained the stipulation that she should maintain a speed of 33 knots for six hours; at her trials, however, she averaged 34½ knots. Her consumption of oil fuel on this occasion was 64¼ tons, and as she is fitted to carry 148 tons, her radius of action at this enormous speed is 435 knots, and at 14 knots, which is known now as the cruising speed, she is estimated to cover 1,500 miles. Though 270 feet in length she is only 25 feet beam. She is constructed entirely of high tensile steel, the tensile strength ranging from 37 to 40 tons per square inch. Her three screw propellers are driven by turbine engines, and it has been found that with oil fuel she can attain her full speed in less time than would be possible were her furnaces fed with coal. Her armament consists of three 12-pounder rifled quick-firing breech-loading guns, two of which are forward and one aft, and two revolving tubes on deck for firing 18-inch torpedoes.