The power which is theoretically required to compress a gas under constant temperature, in a compressor free from losses, from a given inlet pressure to a given discharge pressure.

The proper return port of a discharged seaman.

The short deckhouse or main hatchway which is raised above the level of the cabin top or coachroof.

To make fast. To bend a sail, is to make it fast to the yard. To bend a cable, is to make it fast to the anchor. A bend, is a knot by which one rope is made fast to another.

(1) The mast section next above the topmast and and below the royal mast. (2) The yard supported by that mast. (3) The third lowest square sail. It is stretched between the topgallant yard and the top yard.

In trouble.

Break horse power

A control line that adjusts tension along the foot of the sail, pulling the clew away from the tack; used to maintain proper sail shape.

The dimensionless number obtained when the difference between maximum and minimum instantaneous shaft speeds during one period is divided by the arithmetic mean of these two.

Sailor's name for the north star, Polaris, which for all practical purposes remains fixed above the north pole, bearing north from everywhere in the northern hemisphere, making it a true aid to navigation.

The direction and speed of the wind as it appears to those on board, relative to the speed and direction of the boat; combination of the true wind and the wind caused by the boat's movement through the water.

Same as not under command.

A listing of a particular boat's steering deviation on each point of the compass

Steel wire, used to support over-the-side sampling apparatus

Said of a seaman who has retired from sea service.

Are load carrying machine elements permitting some degree of motion in which the lubricant is air or some other gas.

When a vessel fills with water and sinks.

A ring or hoop of metal.

A squally wind sometimes accompanied by rain, observed as a dark cloud stretched across the horizon.