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intermediate shaft

A shaft that is driven by one shaft and drives another. Nichols, 1

intermediate transfer point

The point along a conveyor, which may already be carrying a load, at which
coal is delivered from another panel conveyor. Nelson

intermediate vein zone deposit

A deposit thought to have been formed at a depth ranging from 4,000 to
12,000 ft (1.2 to 3.7 km) below the surface and at a temperature between
175 degrees C and 300 degrees C. Such a deposit may take the form of a
fissure vein, a series of parallel fissures called a sheeted zone, a
replacement of the wall rock of fissures, or a large disseminated deposit.
Much of the gold, silver, copper, lead, and zinc of the Western United
States comes from these deposits. Lewis

intermetallic compound

An intermediate phase in an alloy system, having a narrow range of
homogeneity and relatively simple stoichiometric proportions, in which the
nature of the atomic binding can vary from metallic to ionic.
See also:intermediate constituent

intermittent cutter

Coal-cutting machine of the pick machine and breast machine type. They are
called intermittent cutters because they must be frequently reset, whereas
with continuous cutters, a continuous cut can be made the full width of
the face without stopping the machine. Kiser

intermittent filters

These usually consist of a number of filtering leaves that are simply
rectangular frames carrying filter cloth on the outer surface. A number of
these leaves are mounted in a suitable tank, and the clear liquid passes
through the filter cloth and out through pipes leading from the interior
of each filter leaf. The solid material forms a cake on the outside of the
leaf. Newton, 1

intermontane

Lying between mountains.

internal-discharge bucket elevator

A type of bucket elevator having continuous buckets abutting, hinged, or
overlapping; designed for loading and discharging along the inner boundary
of the closed path of the buckets. Syn:internal elevator
See also:bucket elevator

internal drainage

Drainage that does not reach the ocean by surface streams, such as
drainage toward the lowermost or central part of an interior basin. It is
common in arid and semiarid regions, as in western Utah. Stokes

internal elevator

See:internal-discharge bucket elevator

internal ribbon conveyor

A trunnion-supported, revolving cylinder, the inner surface of which is
fitted with continuous or interrupted ribbon flighting.

internal stress

Residual stress existing between different parts of metal products, as a
result of the differential effects of heating, cooling, or working
operations, or of constitutional changes in the solid metal. CTD

internal waste

a. Barren rock between two or more bands (veins) or reef which are mined
simultaneously. Beerman
b. See:horse

international ampere

The electric current that, when passed through a solution of silver
nitrate in water, will deposit silver at the rate of 0.001118000 g/s. The
unit of current in common use. CTD

International Ellipsoid of 1930

Equation relating variation of gravity with latitude, adopted by an
international commission as best expressing the normal gravity field of
the Earth to the approximation of an ellipsoid of revolution.

international metric carat

See:carat

interpenetration twin

Two or more individual crystals twinned into such a position that they
penetrate one another. See also:penetration twin
juxtaposition twin. Fay

interphase

In physical chemistry, the transition layer, zone of change, zone of
shear, or zeta layer, through which the characteristic qualities of each
contacting phase diffuse outward with diminishing strength toward the
adjoining phase. Not an interface, since the division is not sharp.
Pryor, 3

interpolation

Estimation of a statistical value from its mathematical or graphical
position intermediate in a series of determined points.

interpolation of contours

The process of drawing contour lines by inferring their plan position and
trend from spot levels or from other contours, assuming the intervening
ground to have uniform slope. Where the spot levels are sparse, the
process requires knowledge of the land or lie of the seams.
See also:contour plan

interrupter

A device, usually automatic, for rapidly and frequently breaking and
making an electric circuit, as in an induction coil. Standard, 2