=trysail mast=—In old ships a mast for hoisting a trysail. (Seldom seen.) =tug=—A small, powerful vessel usually propelled by steam and used to assist larger ships about protected waterways. Tugs are also used to tow barges or almost anything that can float. In the narrow waters of harbours and particularly in going alongside piers and quays, large ships need the assistance that these small vessels give them. There are also larger tugs for use in towing barges or other vessels at sea. These are known as sea-going tugs. =turret=—An armoured turntable in which the larger guns of warships are mounted. =turret steamer=—A steamer which, below the water line, is similar to other ships, but which above the water line has its sides turned abruptly in, so that its main deck is greatly narrower than its water-line beam. For illustration see page 131. =twin screw=—A ship equipped with two propellers is said to be a _twin screw_ ship. =umiak=—An open boat used by the Eskimos and some Northern Indians. It is made up of a frame covered with skins. Its size varies, but an average size would probably be in the neighbourhood of twenty feet in length. =vessel=—From the French _vaissel_. A general term for all craft larger than a rowboat. =vinta=—A Philippine name for one type of outrigger canoe. =waist=—Actually that part of a vessel between the beam and the quarter. In old ships with sterns highly raised it was that portion forward of this raised section—that is, the section of the deck that was lower than the rest. =wake=—The track a vessel leaves behind her on the surface of the water. =watch=—To stand a watch on board ship is to be on duty for a given time, usually, but not always, for four hours. =water sail=—A small sail sometimes set beneath the foot of a lower studding sail. Rare. =ways=—An incline built for a working foundation on which to erect the hulls of ships. When the ship is ready to be floated, it is slid, generally stern first, from the ways into the water. =weather=—As a nautical expression this term is applied to any object to windward of any given spot; hence, the _weather_ side of a vessel is the side upon which the wind blows. A vessel is said to have _weathered_ a gale when she has lived safely through it. =weigh=—To lift the anchor from the bottom is to weigh anchor. =well=—A depression sometimes built in the decks of yachts or sailboats which is not covered over by a deck. It is often called a cockpit, and is for the convenience and protection of passengers and crew. (2) An opening leading to the lowest part of the bilge, in which the depth of bilge water may be measured. =whaleback=—A disappearing type of steamer once common on the American Great Lakes. =whaleboat=—A boat that is sharp at both ends and is propelled by oars. This type was used by whalers, and is now common on ships of war, because of its seaworthiness, ease of handling, and sturdiness.