You take the largest possible number of the best possible guns that can be fired in combination from one vessel as a single battery. You group them conveniently by pairs in turrets. You put the turrets so that there is the widest possible arc of fire for every gun and the least possible blast interference. This regulates the position of the turrets and the spacing between them. You draw a line around the arrangement of turrets thus arrived at, which gives you the deck of the ship. You then build a hull to carry this deck or great gun platform. It must be very big and very long. Next you see what room you have got inside this hull for engines to drive it, and from this and from the length you get the speed. Last of all you decide on the armour. All these calculations and considerations act and react upon one another at every stage, and the manner in which the Royal Corps of Constructors can juggle with these factors, and the facility with which the great chiefs and masters of battleship design like Sir Philip Watts and Sir Eustace Tennyson-D’Eyncourt and their faithful confederate Sir Henry Oram, the Chief Engineer, were able to speak on these matters were marvellous beyond belief. In a few hours, or at most in a few days, one could be told the effect of an alteration in any one set of conditions upon every other set of conditions. On this vast process of juggling and higgling we now embarked. From the beginning there appeared a ship carrying ten 15–inch guns, and therefore at least 600 feet long with room inside her for engines which would drive her 21 knots and capacity to carry armour which on the armoured belt, the turrets and the conning tower would reach the thickness unprecedented in the British Service of 13 inches. For less armour you could have more speed: for less speed you could have more armour, and so on within very considerable limits. But now a new idea began to dawn. Eight 15–inch guns would fire a simultaneous broadside of approximately 16,000 lb. Ten of the latest 13·5–inch would only fire 14,000 lb. Therefore, we could get for eight 15–inch guns a punch substantially greater than that of ten 13·5–inch. Nor did the superiority end there. With the increased size of the shell came a far greater increase in the capacity of the bursting charge. It was not quite a geometric progression, because other considerations intervened; but it was in that order of ideas. There was no doubt about the punch. On the other hand, look at the speed. Twenty-one knots was all very well in its way, but suppose we could get a much greater speed. Suppose we could cram into the hull a horse-power sufficient to drive these terrific vessels, already possessing guns and armour superior to that of the heaviest battleship, at speeds hitherto only obtained by the lightly armoured 12–inch gun battle-cruisers, should we not have introduced a new element into naval war?