ght-lined plane figure, and
its sides are triangles, having their vertices meeting in one point,
named its vertex.

PYROTECHNY. The science of artificial fire-works, including not only
such as are used in war, but also those intended for amusement.

Q.

QUADE. An old word for unsteady.--_Quade wind_, a veering one.

QUADRANT. A reflecting instrument used to take the altitude above the
horizon of the sun, moon, or stars at sea, and thereby to determine the
latitude and longitude of the place, &c. &c. It was invented by Hadley.
Also, in speaking of double stars, or of two objects near each other,
the position of one component in reference to the other is indicated by
the terms, _north following_, _north preceding_, _south following_, or
_south preceding_, the word quadrant being understood.--_A gunner's
quadrant_, for determining the gun's angle of _elevation_. The long arm
is inserted into the bore, while the short one remains outside, with a
graduated arc and plummet, showing the inclination. For _depression_, on
the contrary, the long arm must be applied to the face of the piece.
Also, a graduated arc on the carriage showing, by an index on the
trunnion, the gun's elevation above the plane of its platform; first
applied by the gallant Captain Broke.--The _mural quadrant_, was framed
and fitted with telescope, divisions, and plumb-line, firmly attached to
the side of a wall built in the plane of the meridian; only used in
large observatories.--_Senical quadrant_, consists of several concentric
quadratic arcs, divided into eight equal parts by radii, with parallel
right lines crossing each other at right angles. It was made of brass,
or wood, with lines drawn from each side intersecting one another, and
an index divided by sines also, with 90 deg. on the limb, and two sights
on the edge, to take the altitude of the sun. Sometimes, instead of sines,
they were divided into equal parts. It was in great use among the French
navigators, from its solving the problems of plane sailing.

QUADRATE, TO. To trim a gun on its carriage and its trucks; to adjust it
for firing on a level range.

QUADRATURE. The moon is said to be in quadrature at the first and last
quarter, when her longitude differs 90 deg. from that of the sun.

QUADROON [from L. _quatuor_, four]. The offspring of a mulatto woman and
a white man.

QUAGMIRE. A marsh in which, from its concave and impermeable bottom, the
waters remain stagnant, renderi