Forced by treaty to keep the tonnage of a battleship down to 10,000, Germany sprang two surprises in building its “pocket” dreadnaughts, one of which is shown on the opposite page. These two unique features were electric-welded plates, which saved 500 tons under the conventional riveting method, and the introduction of Diesel engines in heavy warships. By saving weight through the abolishment of rivets, it was possible to install heavier. armament and extremely powerful engines -which stretch over one-fifth of the ship’s total length - developing extraordinary speed. The eight sets of two-stroke Diesel engines are rated at 6,750 horsepower each, and each group of four engines drives one-propeller shaft. The principal armament consists of forward and aft turrets carrying three eleven-inch guns each. In addition there are several lighter guns, anti-aircraft batteries and torpedo tubes. A seaplane is carried just aft of the funnel, launched by catapult.