mp nozzles.

NUBECULAE, MAJOR AND MINOR. The _Magellanic clouds_ (which see).

NUCLEUS OF A COMET. The condensed or star-like part of the head.

NUDDEE. A Hindostanee word for a river.

NUGGAR. A term in the East Indies for a fort, and also for an alligator.

NULLAH. A ravine or creek of a stream in India.

NUMBER. The number on the ship's books is marked on the clothing of
seamen; that on a man's hammock or bag corresponds with his number on
the watch and station bill. The ships of the royal navy are denoted by
flags expressing letters, and when passing or nearing each other the
names are exchanged by signals.--_Losing the number of the mess_, is a
phrase for dying suddenly; being killed or drowned.

NUMERARY OR MARRYAT'S SIGNALS. A useful code used by the mercantile
marine, by an arrangement of flags from a cypher to units, and thence to
thousands. (_See_ SIGNALS.)

NUN-BUOY. A buoy made of staves, somewhat in the form of a double cone;
large in the middle, and tapering rapidly to the ends; the slinging of
which is a good specimen of practical rigging tact.

NURAVEE YAWL. A corruption of _Norway yawl_ (which see).

NURSE. An able first lieutenant, who in former times had charge of a
young boy-captain of interest, but possessing no knowledge for command.
Also, a small kind of shark with a very rough skin; a dog-fish.

NUT. A small piece of iron with a female screw cut through the middle of
it, for screwing on to the end of a bolt.

NUTATION. An oscillatory motion of the earth's axis, due chiefly to the
action of the moon upon the spheroidal figure of our globe.

NUTS OF AN ANCHOR. Two projections either raised or welded on the square
part of the shank, for securing the stock to its place.

NYCTALOPIA. _See_ MOON-BLINK.

O.

O. The fourth class of rating on Lloyd's books for the comparative
excellence of merchant ships. But insured vessels are rarely so low.
(_See_ A.)

O! OR HO! An interjection commanding attention or possibly the cessation
of any action.

OAK. _Quercus_, the valuable monarch of the woods. "Hearts of oak are
our ships," as the old song says.

OAKUM [from the Anglo-Saxon _aecumbe_]. The state into which old ropes
are reduced when they are untwisted and picked to pieces. It is
principally used in caulking the seams, for stopping leaks, and for
making into twice-laid ropes. Very well known in workhouses.--_White
Oakum._ That which is formed from untarred ropes.

OAKUM-BOY.