Any object that a navigator may use to find his position, such as permanent land or sea markers, buoys, radiobeacons, and lighthouses.

(1) The alternate rise and fall of the bow of a vessel proceeding through waves; also called hobby horsing (2) The theoretical distance advanced by a propeller in one revolution. (3) Tar and resin used for caulking between the planks of a wooden vessel.

Self Contained underwater Breathing Apparatus - see Aqualung.

Short pieces of line fastened to the sail at reef points, used for tying a reef to reduce sail area. The reef line will pass through reef cringles, which will become the new tack and clew of the reefed sail.

The time allotted to a man to stand at the helm.

The point where the bottom and the sides of a ship join.

Strop inserted between two hawsers, and weaker than the hawsers, so that strop, and not hawsers, will part with any excessive strain.

A place where boats can find fuel, water and other services. Marinas also contain slips where boats can stay for a period of time.

The maximum continuous operating pressure as designed by the manufacturer.

A pointed metal spike, used to separate strands of rope in splicing.

The stationary seating surface, the inlet of a valve.

An object that might not allow safe operation. A group of rocks just under the water or a submerged wreck could be a navigational hazard.

To sail closer to the wind than another boat on the same tack.

Landfall. To reach shore.

A single inlet compressor with the impeller or impellers mounted on a shaft supported by two bearings in a pedestal, with the driver coupled to the compressor shaft.

A container fitted with a solid removable roof, or with a tarpaulin roof so the container can be loaded or unloaded from the top.

Light lines from the topping lift to the boom, forming a cradle into which the mainsail may be lowered.

The officer on board responsible for the navigation of the ship.

Old three-masted trading vessel which was square-rigged on the fore and main masts, and lateen rigged on the mizzen mast. Similar to the Caravel, but larger and more robust.

A document required and issued by some national governments authorizing the importation of goods.