One of the greatest improvements made at the end of the eighteenth century was the raising of the lower battery further above the water, so as to enable the heavy guns to be fought in all weathers. It was frequently observed that the old British men-of-war of seventy-four guns when engaging a hostile vessel to leeward were, on account of the crankness of the ship and the lowness of the battery, obliged to keep their lower ports closed; whereas the French ships, which were comparatively stiff, and carried their lower guns well above the water, were enabled to fight with the whole of their battery in all weathers. [Illustration: FIG. 58.--British first-rate. 1794.] After the capture of the _Commerce de Marseille_, an English first-rate, named the _Caledonia_, to carry 120 guns, was ordered to be laid down. She was not, however, commenced till 1805. Her dimensions and proportions closely approximated to those of her French prototype, and need not, therefore, be more particularly referred to. She was the first 120-gun ship built in this country. [Illustration: FIG. 59.--Heavy French frigate of 1780.] In the year 1812 the United States declared war against Great Britain. The struggle was memorable for several naval duels between the frigates of the two nations. When the war broke out the United States possessed some frigates of unusual dimensions and armament. The British cruisers were quite overmatched, and in several instances were captured. In consequence of these disasters a new and improved class of frigate was introduced into the Royal Navy. What had happened in the case of the frigates took place also in regard to the sloops employed as cruisers. They were completely outmatched by the American vessels of corresponding class, and many of them were taken. [Illustration: FIG. 60.--Heavy French frigate of 1780.] In 1815, on the conclusion of the long wars with France, there was, of course, a marked diminution in the number of ships built for purposes of war. The _Howe_, of 120 guns (Fig. 61), is given as an illustration of a first-rate of this period. During the earlier years of the present century great improvements were introduced by Sir Robert Seppings and others into the structural arrangements of ships. During the long wars abundant experience had been gained as to the particular kinds of weakness which ships exhibited when exposed to the strains produced by waves. It had been felt for many years that the system of building was very defective, and the life of a man-of-war was consequently short, only fifteen years for a ship built of English oak in the Royal dockyards, and about twelve years for similar vessels built in private yards. Amongst the greatest defects was the absence of longitudinal strength to enable a ship to resist the effects of hogging and sagging strains in a sea-way. [Illustration: FIG. 61.--The _Howe_. 1815.]