Photograph by E. Sankey, Barrow.
It is not only in the larger ships, however, that examples of such extraordinary development are to be found. Progress is shown by the smaller vessels in no less degree. The continually changing conditions of commerce have necessitated as many changes in the construction and armament of vessels whose duty it would be in time of war to protect commerce at sea, or maintain order in estuaries and rivers.
The Dartford, belonging to the “town” class of cruiser, may be regarded as one of the best existing specimens of the modern smaller cruiser. She is of 5,250 tons displacement, as compared with 4,800 tons in the Liverpool, one of the earliest of her class, the addition being largely required to carry an increase in her fighting power, as her armament includes eight 6-inch quick-firers, all well protected, and several smaller guns, as compared with two 6-inch guns and ten 4-inch guns in her preceding sisters. The machinery is of the same type and power as that installed in the earlier “town” cruisers, and in view of the high efficiency of the Liverpool’s engines at her speed trials, the Dartford was expected to attain a speed of twenty-six knots. Besides her coal-bunkers at the sides, the Dartford has an armoured deck of nickel steel, with sloping sides extending well below the water-line. Her turbine machinery of 22,000 shaft h.p. is contained in three separate engine-rooms, and there are three separate boiler-rooms for her twelve water-tube boilers. Oil fuel is carried in her double bottom. She has two masts fitted with wireless telegraphy apparatus, and on the foremast is a platform from which the gun-fire can be electrically directed.
Some cruisers are distinctly lighter versions of battleships. As developments of the swift battleship of the Magnificent and Duncan types came the armoured cruisers Cressy, in 1899, Drake, in 1902, and the belted cruisers Black Prince, in 1904, and Minotaur, in 1906, whence there developed the cruiser-battleship Inflexible in 1907.
The Dreadnought cruisers as much surpass the preceding types of cruisers as the Dreadnought battleships surpassed the Majestics, etc. For that matter, Dreadnought cruisers, like the Princess Royal, as well as the Queen Mary now being built, “could steam round a fleet of pre-Dreadnought ships and fire when it suited them, keeping beyond the range which would enable the old battleship guns to penetrate the armour of the modern cruiser.”[54]
The last of the Dreadnought cruisers launched to the time of writing, the Princess Royal, is the largest warship ever built by a private firm in England for the British Government, although she is stated to be exceeded by the battleship Rio de Janeiro, under construction at Newcastle for the Brazilian Government, which is asserted to have a displacement of 32,000 tons.
The Princess Royal is a cruiser copy of the battleship Conqueror, launched the same day. The principal differences between the two vessels are that the cruiser has a pair less of the 13.5-inch guns, and also has her side armour 2 inches less in thickness, in order that she may steam thirty knots or more in place of the battleship’s twenty-one. Her beam is the same as that of the Conqueror, but in order to give her speed she is 700 feet over all as against the battleship’s 545 feet. In fighting power the Conqueror is superior to the Princess Royal, the latter having only eight big guns. An idea of the enormous power required to drive these ships at the necessary speed, and especially of the increase in power as between the two vessels, is shown by the fact that turbine engines of 27,000 h.p. will give the battleship a speed of twenty-one knots, but the thirty knots of the cruiser require engines developing 70,000 h.p., or 27,000 more than the Indefatigable, which has done twenty-nine knots. The vessel is to be completed for sea by March, 1912.
FRENCH CRUISER “ERNEST RENAN.”
Photograph supplied by Société Anonyme des Chantiers et Ateliers de Saint Nazaire.