"The engines are placed amidships, and each vessel has spacious cabin accommodation aft, as it is intended that they may be used either as despatch or torpedo boats. For the latter purpose the cabin framings above deck are removed and replaced by steel plating. They are steered from the cabin, there being a look-out for the steersman just above deck level. The deck is clear of all obstructions, the two funnels being placed one on either side. They are fitted with balanced rudders and steer well, answering their helms very quickly." The trials of these two torpedo boats are taken from the _Engineer_ under date the 19th of July, 1878. At that time these boats completely eclipsed in speed everything that had hitherto been done. At Fig. 160 is shown in elevation this type of torpedo launch. "The trials were personally conducted by Mr. Yarrow, under the superintendence of the authorities from Whitehall, and consisted in a two hours' run without stopping, during which time the boats were tested at the measured mile at Long Reach. Each boat was run six times over the mile, three runs with the tide and three runs against it. The boats and machinery are similar in every respect, excepting that No. 419 is fitted with a three-bladed propeller, and No. 420 a two-bladed one, their diameters and pitch being the same in both cases. The weights on board were accurately weighed, and amounted to 6 tons in each boat, including coals, water, crew, and ballast. "_Trial of No. 419._ Min. Sec. Knots per hour. 1st run down occupied 2 36 23·076 1st run up " 3 20 18·000 2nd run down " 2 35 23·226 2nd run up " 3 16 18·367 3rd run down " 2 32 23·684 3rd run up " 3 14 18·557 Mean of the six runs, 20·818 knots per hour. Mean steam pressure, 115 lbs. per square inch. Vacuum, 23-1/2 inches. Mean revolutions of main engines per minute, 456. "_Trial of No. 420._ Min. Sec. Knots per hour. 1st run down occupied 2 33-1/2 23·452 1st run up " 3 25-1/2 17·518 2nd run down " 2 32-1/2 23·606 2nd run up " 3 21 17·910 3rd run down " 2 32 23·684 3rd run up " 3 24 17·647 Mean of the six runs, 20·636 knots per hour. Mean steam pressure, 115 lbs. per square inch. Vacuum, 24 inches. Mean revolutions per minute, 466.