Dugout canoeA dugout canoe or simply dugout is a boat made from a hollowed-out tree. Other names for this type of boat are logboat and monoxylon. Monoxylon (μονόξυλον) (pl: monoxyla) is Greek – mono- (single) + ξύλον xylon (tree) – and is mostly used in classic Greek texts. In German, they are called Einbaum ("one tree" in English). Some, but not all, pirogues are also constructed in this manner. Dugouts are the oldest boat type archaeologists have found, dating back about 8,000 years to the Neolithic Stone Age.
CaulkCaulk or, less frequently, caulking is a material used to seal joints or seams against leakage in various structures and piping. The oldest form of caulk consisted of fibrous materials driven into the wedge-shaped seams between boards on wooden boats or ships. Cast iron sewerage pipe were formerly caulked in a similar way. Riveted seams in ships and boilers were formerly sealed by hammering the metal. Modern caulking compounds are flexible sealing compounds used to close up gaps in buildings and other structures against water, air, dust, insects, or as a component in firestopping.
TroopshipA troopship (also troop ship or troop transport or trooper) is a ship used to carry soldiers, either in peacetime or wartime. Troopships were often drafted from commercial shipping fleets, and were unable to land troops directly on shore, typically loading and unloading at a seaport or onto smaller vessels, either tenders or barges. Attack transports, a variant of ocean-going troopship adapted to transporting invasion forces ashore, carry their own fleet of landing craft. Landing ships beach themselves and bring their troops directly ashore.
Port and starboardPort and starboard are nautical terms for watercraft, aircraft and spacecraft, referring respectively to the left and right sides of the vessel, when aboard and facing the bow (front). Vessels with bilateral symmetry have left and right halves which are s of each other. One asymmetric feature is where access to a boat, ship, or aircraft is at the side, it is usually only on the port side (hence the name). Port and starboard unambiguously refer to the left and right side of the vessel, not the observer.
Pump-jetA pump-jet, hydrojet, or water jet is a marine system that produces a jet of water for propulsion. The mechanical arrangement may be a ducted propeller (axial-flow pump), a centrifugal pump, or a mixed flow pump which is a combination of both centrifugal and axial designs. The design also incorporates an intake to provide water to the pump and a nozzle to direct the flow of water out of the pump. A pump-jet works by having an intake (usually at the bottom of the hull) that allows water to pass underneath the vessel into the engines.
SlipwayA slipway, also known as boat ramp or launch or boat deployer, is a ramp on the shore by which ships or boats can be moved to and from the water. They are used for building and repairing ships and boats, and for launching and retrieving small boats on trailers towed by automobiles and flying boats on their undercarriage. The nautical terms ways and skids are alternative names for slipway. A ship undergoing construction in a shipyard is said to be on the ways. If a ship is scrapped there, she is said to be broken up in the ways.
Survey vesselA survey vessel is any type of ship or boat that is used for underwater surveys, usually to collect data for mapping or planning underwater construction or mineral extraction. It is a type of research vessel, and may be designed for the purpose, modified for the purpose or temporarily put into the service as a vessel of opportunity, and may be crewed, remotely operated, or autonomous. The size and equipment vary to suit the task and availability.
Cable layerA cable layer or cable ship is a deep-sea vessel designed and used to lay underwater cables for telecommunications, electric power transmission, military, or other purposes. Cable ships are distinguished by large cable sheaves for guiding cable over bow or stern or both. Bow sheaves, some very large, were characteristic of all cable ships in the past, but newer ships are tending toward having stern sheaves only, as seen in the photo of CS Cable Innovator at the Port of Astoria on this page.
SeakeepingSeakeeping ability or seaworthiness is a measure of how well-suited a watercraft is to conditions when underway. A ship or boat which has good seakeeping ability is said to be very seaworthy and is able to operate effectively even in high sea states. In 1976, St. Denis suggested four principal terms needed to describe a seakeeping performance. These are: Mission: what the ship is intended to accomplish. The role of the ship while at sea. Environment: the conditions under which the ship is operating.
