The sole reason for the existence of the old line of battleship was that that ship was the only vessel that could not be destroyed except by a vessel of equal class. This meant that a country possessing the largest number of best equipped battleships could lay them alongside the enemy, or off the ports where the enemy were. Transports with the escort of a few battleships could then proceed to make oversea conquests. Squadrons of battleships or cruisers escorting the convoy of merchant ships and keeping the line of communications open. In each case the battleship, being able to protect everything it had under its wing from any smaller vessel, was the ultimate naval strength of the country. _Then_ it was that, by means of the battleship only, was the command of the sea gained and held. _Let us be quite clear on the matter, it was solely from the fact that the battleship was unassailable by any vessel except a battleship that made the command of the sea by battleships a possibility!_ Hence battleships came to symbolise naval sea strength and supremacy. For this reason battleships have been built through every change of construction and material, although by degrees other vessels not battleships have arisen which can attack and destroy them. Here therefore there is good ground for inquiry whether the naval supremacy of a country can any longer be assessed by its battleships. To build battleships merely to fight enemy’s battleships, so long as cheaper craft can destroy them, and prevent them of themselves protecting sea operations, is merely to breed Kilkenny cats unable to catch rats or mice. For fighting purposes they would be excellent, but for gaining practical results they would be useless. This at once forces a consideration as to how a battleship differs from an armoured cruiser. Fundamentally the battleship sacrifices speed for a superior armament and protective armour. It is this superiority of speed that enables an enemy’s ships to be overhauled or evaded that constitutes the real difference between the two. At the present moment _naval experience is not sufficiently ripe to abolish totally the building of battleships_ so long as other countries do not do so. _But it is evidently an absolute necessity in future construction to make the speed of the battleship approach as nearly as possible that of the armoured cruiser._ Next consider the case of the armoured cruiser.