other articles of
mess service.

META-CENTRE. That point in a ship where a vertical line drawn from the
centre of cavity cuts a line perpendicular to the keel, passing through
the centre of gravity. As this depends upon the situation of the centre
of cavity, the meta-centre is often called the _shifting-centre_. Safety
requires this point to be above the centre of gravity.

METAL. A word comprehending the great guns, or ordnance generally, of a
ship or battery.

METEINGS. The measurement and estimate of timber.

METEOR. _See_ COMPASANT, WATER-SPOUT, &c.

METEORITES. Meteoric stones which fall from the atmosphere, composed of
earthy and metallic substances, in which iron, nickel, &c., enter
largely.

METEOROLOGIC TELEGRAPHY. The sending of telegrams to various stations at
home and abroad, with the object of improving the science of
meteorology, and issuing storm warnings, &c.

METONIC CYCLE. A cycle of 19 years, which contains 235 lunations, and
results in a correspondence of the solar and lunar years. The discovery
of this astronomical period may be safely assigned to Meton in 432 B.C.

MEW [Anglo-Saxon _maew_]. A name for the sea-gull.

MIASMA. An impure effluvium in the air--proceeding from marshes or moist
ground acted upon by solar heat--by which malaria fevers, particularly
intermittents, are produced.

MICROMETER. An instrument used to measure small angles, diameters, and
distances of heavenly bodies.

MID. The intermediate or middle part of anything. Also, _per
contractionem_, a midshipman.

MID-CHANNEL. Implies half way across any river, channel, &c.

MIDDLE BAND. One of the bands of a sail, to give additional strength.

MIDDLE-LATITUDE SAILING. A method of converting departure in difference
of longitude, and _vice versa_, by using the middle latitude instead of
the meridional parts, as in Mercator's sailing.

MIDDLE-TIMBER. That timber in the stern which is placed amidships.

MIDDLE-TOPSAIL. A deep-roached sail, set in some schooners and sloops on
the heel of their top-masts between the top and the cap. A modification
of this, under the name of a lower top-sail, is now very common in
double-topsail-yarded ships. (Cunningham's top-sails.)

MIDDLE-WALES. The three or four thick strakes worked along each side
between the lower and middle-deck-ports in three-deckers.

MIDDLE-WATCH. The portion of the crew on deck-duty from midnight to 4
A.M.

MIDDLE-WATCHER. The slight meal snatched by offi