A frigate, according to an old work of 1771, was defined as "a light nimble ship built for the purposes of sailing swiftly. These vessels mount from twenty to thirty-eight guns, and are esteemed excellent _cruisers_." The name was derived from _fregata_, a Mediterranean vessel propelled both by sails and by oars. It is said the British navy was the first to adopt frigates for use in war, but the French, and afterwards the Americans, were generally successful in building the finest vessels of this class. These ships were full-rigged, with three masts, and carried all their principal guns in one battery on the main deck. The corvette may be regarded as a smaller frigate, but was not square-rigged on her mizzen-mast, and carried her main battery on her upper deck. This later type of cruiser outlasted the frigate by some years, and the last of them, such as the _Opal_ and other corvettes of the "Jewel" class, were very handsome vessels, though by no means so formidable as the pole-rigged cruisers which took their place. The frigates in the old French War were considered "the eyes and ears of the fleet". They sought out and reported the enemy, they attacked his cruisers and commerce and protected our own, and fully justified their name and the general reputation for smartness which they were accorded. The duties of our cruisers of to-day are of a very similar kind, although the invention of wireless telegraphy and the aeroplane has supplemented and to some extent superseded their scouting work. As for what they have actually done, we have only to recollect the various incidents of the Great War as regards its aspects at sea. Acting in unison with those of France and Japan, they have swept German commerce and German cruisers from the face of the ocean, and so far, except for shore bombardments and submarine attacks, have been the only war-vessels engaged on either side. At the time of writing no battleships have as yet been in action against one another, for we may regard all those ships which have been reported in action at sea as cruisers, from the big battle-cruiser _Lion_ down to the destroyers--and even, perhaps, our submarines, which are very useful scouts. Cruisers proper in our navy are now officially classed in three main divisions--"battle-cruisers", "cruisers", and "light cruisers", though a very short time ago they were subdivided into "armoured cruisers", "first-class protected cruisers", "second-class protected cruisers", "third-class protected cruisers", "unarmoured cruisers", "lightly-armoured cruisers", and "scouts". The battle-cruiser is a hybrid and, as this war has proved, a most useful war-vessel. She is not so heavily armed or armoured as a battleship of equivalent age, but has much greater speed. She is as big or bigger, and costs just about as much. Thus the _Lion_ was launched in the same year as the battleship _Orion_--1910. Note the comparison below:--