LAUNCH is the process of removing a vessel from the land to the water. The kk-el of a ship is laid upon a series of wooden blocks, placed 6 or 7 ft. apart, and built up 3 or 4 ft. from the ground, the tops of which lie in a line which slopes downwards to the water at an angle of about five-eighths of an inch to the foot. The whole ship, therefore, when it is finished, slopes downwards with this inclination, and rests upon the blocks just mentioned, and upon suitable timber shores. When the vessel is ready for launching, ways" of planking are laid down parallel to the keel, and at some little distance on each side of it, under the bilges of the ship; they extend into the water a considerable distance below high-water mark. A " cradle' is then built under the ship, of which the bottom is formed of smooth timbers resting upon the ways. Before launching, the under sides of these timbers and the upper sides of the ways are well greased, and the weight of the ship is transferred from the keel.blocks to the cradle and ways. Timbers, called "dog
shores," are placed so as to resist the tendency of the ship to slide down until the right moment. When this arrives, at the ceremony of naming the ship takes place; the dog-shores are knocked away, and the vessel glides stern foremost into the water. As soon as the water removes the weight of the vessel from the cradle, the latter breaks up into pieces.
The Great Eastern, owing to her immense length, was built with her to the water; but owing to excessive friction, it took three months' exertion, even with the aid of powerful hydraulic rams, to push the immense mass of 12,000 tons into the river.