t-pensions.

PENSTOCK. A flood-gate to a mill-pond. Also used in fortification, for
the purpose of inundating certain works.

PENTAGON. A right-lined figure of five equal sides and angles.

PENUMBRA. The lighter shade which surrounds the dark shadow of the earth
in an eclipse of the moon. Also, the light shade which usually encircles
the black spots upon the sun's disc.

PEON-WOOD. _See_ POON-WOOD.

PEOTTA. A craft of the Adriatic, of light burden, propelled by oars and
canvas.

PEPPER-DULSE. _Halymenia edulis_; a pungent sea-weed, which, as well as
_H. palmata_, common dulse, is eaten in Scotland.

PER-CENTAGE. A proportional sum by which insurance, brokerage, freight,
del credere, &c., are paid.

PERCER. A rapier; a short sword.

PERCH. A pole stuck up on a shoal as a beacon; or a spar erected on or
projected from a cliff whence to watch fish.

PERCUSSION. The striking of one body by another.

PERDEWS. A corruption from _enfans perdus_, to designate those soldiers
who are selected for the _forlorn hope_ (which see).

PERIGEE. That point in the moon's orbit where she is nearest to the
earth; or the point in the earth's orbit where we are nearest to the
sun.

PERIHELION. That point in the orbit of a planet or comet which is
nearest to the sun.

PERIKO. An undecked boat of burden in Bengal.

PERIL, OR PERIL OF THE SEA. Does not mean danger or hazard, but
comprises such accidents as arise from the elements, and which could not
be prevented by any care or skill of the master and crew. (_See_ ACT OF
GOD.)

PERIMETER. The sum of all the sides of a geometrical figure taken
together.

PERIODICAL WINDS. _See_ MONSOON and TRADE-WINDS.

PERIODIC INEQUALITIES. Those disturbances in the planetary motions,
caused by their reciprocal attraction in definite periods.

PERIODIC TIME. The interval of time which elapses from the moment when a
planet or comet leaves any point in its orbit, until it returns to it
again.

PERIPHERY. The circumference of any curved figure.

PERISHABLE MONITION. The public notice by the court of admiralty for the
sale of a ship in a perishable condition, whose owners have proved
contumacious.

PERIWINKLE. The _win-wincle_ of the Ang.-Sax., a favourite little
shell-fish, the pin-patch, or _Turbo littoreus_.

PERMANENT MAGNETISM. The property of attraction and repulsion belonging
to magnetized iron. (_See_ INDUCED MAGNETISM.)

PERMANENT RANK. That given by commission, and which d