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force of crystallization

See:crystallizing force

force oscillator

An instrument to determine the mechanical resonant frequency of a whole
crystal or cut crystal plate. A slowly varying frequency is applied to the
crystal from a signal generator, and the resonant frequency voltage
developed across the crystal is measured with a voltmeter. Also called
drive oscillator.

force pump

a. A pump consisting of a plunger or ram, the up-stroke of which causes
the suction valve to open and the water to rise in the suction pipe. On
the down-stroke of the plunger, the suction valve closes and the contained
water is forced through the delivery valve into the rising main or
discharge pipe. Nelson
b. A pump that forces water above its valves. Zern
c. A pump in which the water is lifted by the force due to atmospheric
pressure acting against a vacuum. Crispin

forcer

a. A small hand pump used in Cornish mining. Standard, 2
b. The solid piston of a force pump. Standard, 2

forcherite

An orange-yellow opal colored with orpiment. Standard, 2

forcing fan

A fan which blows or forces the intake air into the mine workings, as
opposed to an exhaust fan. A mine exhaust fan may become a forcing fan
(with reduced efficiency) when the ventilation is reversed in an
emergency. Nelson

forcing lift

Scot. A set of pumps raising water by a plunger; a ram pump. Also called
forcing set. Fay

forcing set

A pump for forcing water to a higher level or to the surface. CTD

forebay

a. A reservoir or pond at the head of a penstock or pipeline.
Seelye, 1
b. The water immediately upstream of any structure. Seelye, 1

forechamber

An auxiliary combination for gas-fired boilers that provides an
incandescent surface for lighting gas instantly when turned on after being
shut off for any reason. Also called Dutch oven; doghouse. Fay

fore drift

The one of a pair of parallel headings that is kept a short distance in
advance of the other. CTD

forehearth

a. A projecting bay in the front of a blast furnace hearth under the tymp.
In open-front furnaces, it is from the forehearth that cinder is tapped.
Fay
b. An independent settling reservoir into which is discarded the molten
material from a furnace and which is heated from an independent source.
The heavy metal settles to the bottom and the light slag rises to the
surface. Fay
c. A section of a furnace, in one of several forms, from which glass is
taken for forming. ASTM

foreign coal

Coal received at a preparation plant from a source other than that to
which the plant is attached. BS, 5

foreigner

Dark, ovoid inclusion of country rock in granite. Syn:furrener
Arkell

foreign inclusion

A fragment of country rock enclosed in an igneous rock. Syn:xenolith

foreland

A stable area marginal to an orogenic belt, toward which the rocks of the
belt were thrust or overfolded. Generally the foreland is a continental
part of the crust, and is the edge of the craton or platform area.
AGI

forelimb

The steeper of the two limbs of an asymmetrical anticlinal fold.
AGI

forelimb thrust

A thrust fault cutting strata on the steeply dipping flank of an
asymmetrical anticline.

forellenstein

See:troctolite

Forel scale

The basic scale for measuring seawater color. See also:water color
Hy

foreman

The head person; esp., the overseer of a group of workers.
See also:mine foreman; boss. Standard, 2