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spaced loading

a. Loading so that cartridges or groups of cartridges are separated by
open spacers that do not prevent the concussion from one charge from
reaching the next. Nichols, 1
b. See:deck loading

space frame

A three-dimensional frame that is stable against wind pressure without
being braced against any other structure. Hammond

space group

In crystallography, any one of 230 independent combinations of the 14
essentially different kinds of three-dimensional periodicity (Bravais
lattices) with other symmetry operations (point groups, screws, glides).
CF:plane group; Bravais lattice; point group; screw; glide.

space lattice

a. A three-dimensional regularly repeating set of points so arranged as to
determine sets of equally spaced parallel planes in various directions
forming polyhedral cells (as in a honeycomb). Specif., a set of such
points occupied by the atoms of a crystal.
b. The pattern formed by the spatial distribution of atoms or radicals in
a crystal. See also:crystal pattern; lattice. Hackh
c. Any one of 14 infinite three-dimensional arrays of points such that
each point is in an identical point environment. Syn:Bravais lattice
CF:net

spacer

a. A piece of metal wire twisted at each end so as to form at one end a
guard to keep the explosive in a shothole in place and at the other end
another guard to hold the tamping in its place, thus providing an open
space between explosive and tamping. When this is provided, the charge
constitutes a cushion shot. Zern
b. Piece of wood doweling which is interposed between charges to extend
the column of explosive. Nelson
c. A marker block. Also called spacer block. Long
d. The tapered section of a pug joining the barrel to the die; in this
section beyond the shaft carrying the screw or blades, the clay is
compounded before it issues through the die. Dodd

spacing

The distance between adjacent shotholes in a direction parallel to the
quarry or other face. Nelson

Spackman System

See:coal constituent classification

spad

a. A means of marking an underground survey station that consists of a
flat spike in which is drilled a hole for the threading of a plumbline.
BS, 7
b. See:spud

spade drill

See:flat drill

spade-end wedge

A type of deflecting wedge in boreholes. See also:deflecting wedge
Long

spadiard

Corn. A worker in the tin mines. Also called spalliard.
Standard, 2

spake

A term used in South Wales for a train of personnel carriages, for use on
the main slants at the beginning and end of each shift. The seats are so
arranged that they are horizontal when the carriage is on the inclined
slant. See also:man-riding car; man-riding conductor. Nelson

spall

a. A relatively thin, commonly curved and sharp-edged piece of rock
produced by exfoliation.
b. To break off in layers parallel to a surface.
c. To break ore. Pieces of ore thus broken are called spalls. Also
spelled: spawl.

spalliard

Eng. A pickman; a working miner. A laborer in tinworks. Also spelled
spallier.

spalling

The chipping, fracturing, or fragmentation, and the upward and outward
heaving, of rock caused by the action of a shock wave at a free surface or
by release of pressure. Syn:exfoliation

spalling floor

A place for breaking ore with a 4- to 5-lb (1.8- to 2.3-kg) sledge hammer.

span

a. The horizontal distance between the side supports or solid abutments
along sides of a roadway. See also:abutment; pressure arch.
Nelson
b. The horizontal distance between the supports of a bridge, arch, beam,
or similar structural member. See also:clear span; effective span.
Hammond

spangle gold

Aust. Smooth, flat scales of gold.

spangolite

A trigonal mineral, Cu6 Al(SO4 )(OH)12 Cl.3H2
O ; soft; vitreous; dark green; in Cochise County, AZ.

Spanish chalk

A variety of steatite in Aragon, Spain.

Spanish emerald

Emerald of the finest quality (presumably from South America).
Schaller