promising the Admiralty the speed required. This exceeded by a considerable margin the rates of steaming of the French sea-going torpedoboats which had then been recently constructed in large numbers. The trial speed of 27 knots was obtained with little or no difficulty, and this success encouraged the Admiralty to demand even higher rates of steaming, with the result that gradually the standard was raised and the British fleet was provided with a large number of torpedo-boat destroyers of 30 knots trial speed. The 30-knot destroyers proved in every respect successful, even before the adoption of the water-tube boiler, but in order to obtain the increased speed the size of the boats had to be augmented. Some of the earlier 27knot boats displaced as little as 240 tons of water and developed between 3000 and 4500 indicated horse-power.

With the demand for a greater speed the displacement of the boats rose rapidly to 300, and in some cases as much as 330 tons. Each builder was allowed a certain freedom in the design of the boats included in the

contract, with the result that the torpedo flotillas of the British fleet have never been homogeneous. The main point was that the speed for which the Admiralty stipulated should be obtained under a light load, and so long as the vessels were constructed with what the Admiralty considered a fair margin of strength, the builders suffered from little interference in working out their designs, though the boats of each firm bore a certain likeness. Under the urgent demand for increased speed the indicated horse-power rose to 6000, and in some boats reached 6500. In a few vessels, even higher speeds, ranging up to 32 and 33 knots, were guaranteed, but those efforts were not entirely successful.

The "Express," the "Albatross," and several others of these swifter vessels gave considerable trouble during their trials, and for a long period failed to reach the maximum speed. The difficulties experienced with these craft seem to indicate that 30 knots was the maximum speed which could be obtained from vessels of 300 tons displacement; even this

rate of steaming was possible only in smooth water and with a light load, and in service conditions it fell off to the extent of 2 or 3 knots, so that the service speed amounted to a little over 27 knots.

Some builders, however, believed that more work could be got out of such destroyers than had hitherto been obtained, and Messrs. Laird Brothers, of Birkenhead, England, made a very plucky effort to push the "Express" beyond the performances attained by any vessels at that date. Launched in 1897, this vessel was to have attained a speed of 33 knots. According to a Parliamentary paper, it made 27 preliminary and 10 official trials without giving satisfaction, although no less than 9000 indicated horse-power were obtained. About 30 knots appeared to be the maximum for vessels using reciprocating engines.

About this time, however, the Admiralty entrusted the Parsons Company with a contract to enable them to see what could be done with a vessel fitted with their turbine machinery. The little ship "Viper" was ordered in March, 1898, was completed in September, 1899, and on her trials proved a remarkable success. Under the Admiralty's contract conditions she attained the remarkable speed of 34 knots, with a maximum of 36 knots. This ship This ship proved a veritable 30-knot vessel in the open seaway under ordinary service conditions. Unfortunately, her career was cut short through misadventure, she ran ashore off the Channel islands in a fog and became a total wreck.

As soon as these 30-knot destroyers were ready for service, they were commissioned and subjected to the severest possible tests. Experience showed that they were safe, reliable vessels of high speed when handled with skill in fair weather. They were constructed primarily for acting from a base as a reply to the menace of the large number of torpedo-boats which in time of war would infest

the English Channel. Their capabilities for sea work proved so remarkably good, however, that the admirals of the squadrons, particularly in the Mediterranean Sea, acquired the habit of employing them as "sea gallopers," and even under the severe conditions of rough weather which were often experienced, the best of them did not reveal any signs of weakness. Many of them suffered from breakdowns, but there was reason to believe that these troubles were due more to the inexperience of the engineering staff, new to quick-running engines and watertube boilers, than to any inherent defects of the ships. Naval officers expressed themselves highly gratified with the type of vessel which had been provided, and their confidence. was so unbounded that these little vessels were kept at sea for long periods in the roughest weather.

While most of the boats gave excellent results, sea experience convinced the officers in charge that the new vessels were of uneven quality. The freedom which the Admiralty had given the contractors had led in some cases to the scantlings being too fine. So long as the boats were used merely in smooth water they proved successful, but many of them were unfitted for open sea work. In other cases the speed on trial was obtained by severely pressing the destroyers and by high-air pressure.

In passing, it may be noted that a striking feature of the eight destrovers built by Messrs. Yarrow & Co., Ltd., of Poplar, London, for the Japanese Government, was the low air pressure. This is a very important point, because as the boilers grow old they gradually become less efficient from sediment collecting on the inside of the heating surfaces, and soot and other non-conducting materials on the outside. Consequently, the only means of maintaining the efficiency of the machinery, especially of the boilers, is to provide boilers of very large size so that as their evaporative power diminishes in