'Rattler' to 30 lbs. in the 'Vestal,' which of itself shows what an advance must have taken place in the art of boiler construction, and every boiler afloat was on the tubular principle. The interposition of gearing between the crank and main shafts had long been abolished, and the number of revolutions of the engines had risen from, say, fourteen to fifty-six. The question of coal consumption was beginning to awaken attention, and as a consequence compound engines and surface condensers were being toyed with tentatively to that end. The 'Warrior,' though completed in 1861, was still the fastest ship we had, with her speed of 14.3 knots, and it was not then considered likely that this speed would be much exceeded in the future except by a few enthusiasts; but the gift of prophecy is rare, and it is possible that a quarter of a century hence the engines of the 'Blake' will be considered as antiquated as those of the 'Warrior' are now. The engine builders of 1865, however, enjoyed advantages of which their successors of to-day may well be envious. The girders of ironclads, the solid oak beams of frigates or converted line-of-battle ships furnished such sound foundations for the bed-plates of the engines, and, above all, the restrictions in the matter of weight were so comparatively benign, that delightful smoothness of working was the rule, and serious accidents were all but unknown.
We now enter on a new era of naval marine engineering. In 1866 was completed the 'Pallas,' a small ironclad designed by Sir E. Reed, and remarkable for having
