applied to an interval of time in which the same
phenomena recur.

CYCLE OF ECLIPSES. A period of about 6586 days, which is the time of a
revolution of the moon's node; after the lapse of this period the
eclipses recur in the same order as before, with few exceptions. This
cycle was known to the ancients under the name of Saros.

CYCLOID. A geometrical curve of the higher kind.

CYCLONE. _See_ TYPHOON.

CYLINDER. The body of a pump; any tubular part of an engine.--_Charge
cylinder_ of a gun, is the part which receives the powder and ball, the
remaining portion being styled the _vacant cylinder_. Especially in
marine steam-engines, the cylindrical metal tube, with a diameter
proportionate to the power of the engine, of which it may be termed the
chief part, since it contains the active steam. Also, a cartridge box
for the service of artillery. (_See_ CARTRIDGE-BOX.)

CYLINDER-COVER. In the steam-engine, is a metal lid with a hole in the
centre for the piston-rod to work through.

CYLINDER CROSS-HEAD. An adaptation on the top of the piston-rod,
stretching out athwart the cylinder, from the ends of which the
side-rods hang.

CYLINDER ESCAPE-VALVES. Small conical valves at each end of the
cylinder, for the purpose of letting off any water that may collect
above or below the piston.

CYLINDER POWDER. That made upon the improved method of charring the wood
to be used as charcoal in iron cylinders. All British government
gunpowder is now made thus.

CYPHERING. A term in carpentry. (_See_ SYPHERED.)

D.

D. In the _Complete Book_, D means dead or deserted; Dsq., discharged
from the service, or into another ship.

DAB. The sea-flounder. An old general term for a pleuronect or flat fish
of any kind, but usually appropriated to the _Platessa limanda_. The
word is familiarly applied to one who is expert in anything.

DABBERLACK. A kind of long sea-weed on our northern coasts.

DAB-CHICK. The little grebe, _Podiceps minor_. A small diving bird
common in lakes and rivers.

DACOITS. _See_ DEKOYTS.

DADDICK. A west-country term for rotten-wood, touch-wood, &c.

DAGEN. A peculiar dirk or poignard.

DAGGAR. An old term for a dog-fish.

DAGGER-KNEE. A substitute for the hanging-knee, applied to the under
side of the lodging-knee; it is placed out of the perpendicular to avoid
a port-hole. Anything placed aslant or obliquely, now generally termed
diagonal, of which, indeed, it is a corruption.

DAGGER-PI