Eng. The largest lumps of coal sent to the surface, or all coal that is
handpicked or does not pass over screens; also the largest coal that
passes over screens. Fay
a. One of the three main size groups by which coal is sold by the National
Coal Board of Great Britain. Large coal has no upper size limit and has a
lower size limit of 1-1/2 to 2 in (3.8 to 5.1 cm) and embraces large
screened coal, cobbles, and treble sizes. See also:graded coal; smalls.
Nelson
b. Coal above an agreed size without any upper size limit. Also called
lump coal. BS, 5
Gr. Brit. In general, a colliery producing more than 1,500 st/d (1,360
t/d). Nelson
An auger-type coal-cutting machine developed by the U.S. Bureau of Mines
for use in anthracite mining. It can drill holes 1 ft (31 cm) in diameter,
300 ft (91 m) long, and larger holes for shorter distances.
A large knot is one whose average diameter exceeds one-third the width of
the surface on which it appears; but such a knot may be allowed if it
occurs outside the sections of the mine track tie between 6 in and 18 in
(15 cm and 46 cm) from each end.
A large shake is one that exceeds one-third the width of the mine track
tie. A shake not exceeding this limitation and that does not extend nearer
than 1/2 in (1.3 cm) to any surface shall be permissible.
A term applying to mine track ties. A large split is a split exceeding 5
in (13 cm) in length. Splits not longer than 5 in are permissible
providing satisfactory antisplitting devices have been properly applied.
A monoclinic mineral, 4[beta-Ca2 SiO4 ] ; gray; in contact
metamorphosed limestone. CF:bredigite
An orthorhombic mineral, PbZnSiO4 ; forms colorless to white
prisms; in veins at Franklin, NJ.
A type of pile consisting of hollow cylinders that increase resistance
against bending and crumpling. They are esp. useful in shaft sinking in
sand and gravel. Stoces
Steel sections of various forms, made esp. to resist bending, that are
used in place of wooden spiles in forepoling. Stoces
A tool used to reach bedrock when the driven pipe has failed.
An alkalic syenite, grading to monzonite, composed of phenocrysts of two
feldspars (esp. oligoclase and alkali feldspar), often intimately
intergrown, which comprise up to 90% of the rock, with diopsidic augite
and titanaugite as the chief mafic minerals, and accessory apatite
(generally abundant), ilmenite, and titaniferous magnetite, and less
commonly olivine, bronzite, lepidomelane, and quartz or feldspathoids
(less than 10% by volume). Its name, given by Broegger in 1890, is derived
from Larvik, Norway. Also spelled laurvikite. Syn:blue granite
AGI
An active electron device that converts input power into a very narrow,
intense beam of coherent visible or infrared light; the input power
excites the atoms of an optical resonator to a higher energy level, and
the resonator forces the excited atoms to radiate in phase. Derived from
"light amplification by stimulated emission of radiation."
See also:maser
To attach a chain to a haulage rope by wrapping or lapping the end of the
chain around the rope, the other end being attached to a mine wagon.
Mason
a. A native employed to do lashing. See also:lashing
b. See:mucker
A person employed to lash the chains from the tubs to the endless rope, in
underground mechanical haulage. CTD
a. Any of a number of planks nailed inside of several frames or sets in a
shaft to keep them in place. Also called listing. Webster 2nd
b. A binding, generally of light line around the end of a rope.
c. In South Africa, loading broken rock or ore with shovels.
Nelson
d. Shoveling rock downstope to ore passes--work performed by a lasher. A
"lasher-on" connects tubs or trucks to a rope haulage. Also called
mucking. Pryor, 3
A short chain to attach tubs to an overrope in endless rope haulage by
wrapping it around the rope. The chain may be about 12 ft (3.7 m) long, of
low manganese steel, with 3/8-in-diameter (9.5-mm-diameter) standard
links. At one end of the chain, a ring 4 in (10.2 mm) in diameter is
attached to the drawbar hook of the tub, and to a hook about 3/8 in in
diameter to secure it to the rope at the lashing end. On an undulating
road, two lashing chains may be necessary--one forward and one rear of the
tub. Nelson
Extemporized engineering rig for a temporary job. Pryor, 1
A thin, flat diamond with a simple facet at the side; used by Indian
cutters to cover miniature paintings. Also spelled lask. Also called
portrait stone.