Britain at Work
A Pictorial Description of Our National Industries

7 THE BUILDING OF A BATTLESHIP. capable of doing so. At Barrow is a large yard owned by the Vickers company, and building the finest battleships and cruisers. Finally, at Birkenhead is the historic estab- lishment of Laird Brothers. The first step in the building of a battle- ship is the preparation of the design. This is accomplished at the Admiralty, by the Director of Naval Construction’s Department. The Director works in concert with the engineering and gunnery experts of the Navy, and the general outlines of the design are laid clown by the naval officers of the Admiralty Board. These officers, who may have to fight the ship, determine what the guns carried are to be, what the thickness of the armour, what the speed, what the coal allowance. The length of the ship and her draught of water are largely influenced by the size of existing docks. Before finally settling the design, very careful tests are made to ascertain the best “ lines” or form of ship to give a high speed. These tests are rendered possible by the construction of models which are tried in a large tank. By their aid the speed of the ship built, with a given engine-power, can be very accurately determined before- hand, and such unpleasant surprises are guarded against as occur when a ship designed to steam twenty knots is found to be capable only of making nineteen. As soon as the general outline of the design has been settled, and passed by the Admiralty Board, detailed drawings and specifications are prepared. The most im- portant of these are the “lines” of the ship, and to obtain them foreign emissaries are known upon occasions to have offered very large sums. The “ lines ” are a series of plans showing the variations in the section of the ship at various points in her length, the variations in the ground plan of her different decks, and the longitudinal eleva- tion, indicating such matters as her “sheer” forward, or the cutting away of what is known as the “ deadwood ” of the keel aft, a feature in ships which are to be able to turn quickly and in a small circle. If the ships are to be built by contract, these drawings, with detailed specifications, indi- cating exactly the material to be used, the thickness of the plates to be employed, the type of engines and boilers, and a vast