The opening up the back (aft) edge of the mast in which the mainsail luff rope slides when it is hoisted. Some masts have an external sail track.

The frame on the keelson of boat (does not apply on ships) to which the heel of a mast is fitted.

The fitting in the bottom of the boat in which the bottom or heel if the mast sits.

Fittings on the mast to which the forestay and shrouds attach.

A track or groove in the back of the mast to which the sail is attached by means of lugs or the bolt rope.

A term for the captain, a holdover from the days when the captain was literally, and legally, the "master" of the ship and crew. His word was law.

The Captain of a vessel. Highest officer aboard ship. Oversees all ship operations. Keeps ships records. Handles accounting and bookkeeping. Takes command of vessel in inclement weather and in crowded or narrow waters. Handles communications.

U.S. Customs' automated program under AMS. It allows for electronic reporting of inbound (foreign) cargoes in the U.S.

The top part of the mast.

The top of a mast.

The white running light carried by steam vessel underway on the foremast or in the forepart of the vessel.

Also known as a steaming light. The masthead light is a white light that is visible for an arc extending across the forward 225

A design in which the forestay runs to the top of the mast.

Materials

An archaic practice. An acknowledgement of cargo receipt signed by a mate of the vessel. The possessor of the mate's receipt is entitled to the bill of lading, in exchange for that receipt.

Receipt made by Chief Officer, stating the quantity and condition of goods loaded.

The date on which a Bill of Exchange or Letter of Credit becomes due for payment.

(See MALL.)

Maximum allowable working pressure. This data is found on the pressure vessel nameplate and is the maximum pressure at which the lowest set safety valve must be set (stamped).

The maximum static pulling force produced through a vessel’s harbor pile towing test.