it is out into water deep enough to allow a vessel to pass over it. The stem or nose of the vessel is hauled up into the guide on the head of the cradle, which is simply a pair of iron bars bent to the proper shape and bolted on to the cradle. The stern of the vessel being hauled into its proper place, the keel is over the centre of the carriage; the back guides are then lifted up to secure the vessel in its place. The back guides are strong iron bars, working separately on a 4 in. pin, passing through strong uprights bolted to the side of the longitudinal beams at such distances as may be required to suit the length of a vessel. So soon as a vessel is thus fixed in position, the cradle is hauled up until the keel rests its whole length on the cradle, and the bilge blocks being then pulled under the vessel's bottom she is hauled up out of the water, the palls being dropped so soon as the bilge blocks are pulled into their proper position. These palls prevent a vessel running back into the water in the event of its being necessary, from any cause, to take the weight off the machinery, and also serve to keep the cradle in its place when up on the ways. To launch a vessel, the cradle is hauled up sufficiently to allow the palls to be lifted. It is then lowered, by means of the large chain, conveniently near to the water's edge; the large chain is then released, and the cradle and vessel allowed to run out by their own impetus, taking, of course, the small chain. The mode of releasing the large chain is by knocking the pin out of the shackle which secures the return end when passed round the wheel at the head of the carriage, the pin being made conical for the purpose. The impetus caused by running out generally carries the vessel clear of the cradle, but if, from any cause, the vessel does not run out sufficiently fast to clear the cradle, the small chain serves to haul it into deeper water to clear it, and, the engine being reversed, the small chain hauls up the cradle out of the water. It is sometimes required to raise a second vessel when the cradle is occupied. This is effected by blocking the vessel already up off the cradle. To do this wooden blocks are placed under the vessel between all the bilge beams of the cradle, and the weight of the vessel taken off the cradle by wedging these blocks up tightly. To allow the cradle to be removed, and to clear the keel of any vessel requiring it, small pieces of wood, 2 in. thick, are nailed on to the keel blocks on the centre longitudinal beam before a vessel is taken up. When a vessel is tightly wedged up on to the wooden blocks, as described, these small pieces are split out, leaving a space between the keel of the vessel and the cradle. The bilge beams are removed by knocking out the wedges and releasing the ends from the teeth on the centre beam, and taking out the cotter pins on the outer longitudinals. The bottom of the vessel being thus cleared of the cradle, it is hauled out from under by means of the small chain; the bilge beams, etc., are then replaced in position, and the cradle lowered into the water in the usual way, the chains working under the