The Sailor's Word-Book / An Alphabetical Digest of Nautical Terms, including Some More Especially Military and Scientific, but Useful to Seamen; as well as Archaisms of Early Voyagers, etc.

by W. H. Smyth

DIMINUTION OF OBLIQUITY. A slow approximation of the planes of the ecliptic and the equator, at the present rate of 0·485″ annually.

DIMSEL. A piece of stagnant water, larger than a pond and less than a lake.

DING, To. To dash down or throw with violence.

DING-DONG. Ships firing into each other in good earnest.

DINGHEY. A small boat of Bombay, propelled by paddles, and fitted with a settee sail, the mast raking forwards; also, the boats in use on the Hooghly; also, a small extra boat in men-of-war and merchant ships.

DINGLE. A hollow vale-like space between two hills. A clough; also, a sort of boat used in Ireland, a coracle.

DINNAGE. See [Dunnage].

DIP. The inclination of the magnetic needle towards the earth. (See [Dipping-needle].) Also, the smallest candle formerly issued by the purser.

DIP, To. To lower. An object is said to be dipping when by refraction it is visible just above the horizon. Also, to quit the deck suddenly.

DIP of the Horizon. The angle contained between the sensible and apparent horizons, the angular point being the eye of the observer; or it is an allowance made in all astronomical observations of altitude for the height of the eye above the level of the sea.