A carbon monoxide detector consisting essentially of a small glass tube
filled with a powdered chemical; when air is drawn through it, if any of
the gas is present, the powder will change color, its degree of change
depending upon the amount of carbon monoxide present. This device is very
sensitive and will detect gas as low as 0.01%. Kentucky
Pneumatic jig, used in regions where water is scarce, or where the ore
must be kept dry, to concentrate values from sands. Pryor, 3
An electrolytic process of aluminum refining that utilizes three liquid
layers in the reduction cell. An anode of aluminum-copper alloy is used in
a fused fluoride bath. The lighter aluminum, about 99.99% purity, collects
at the cathode above the fused bath. Henderson
Catalytic granules consisting of finely divided manganese dioxide mixed
with copper oxide and a small quantity of silver oxide, and used in gas
mask cannisters to remove carbon monoxide by oxidizing it to carbon
dioxide. With the development of Hopcalite, the problem of providing
adequate protection against carbon monoxide poisoning was solved.
McAdam, 1
An orthorhombic mineral, Zn3 (PO4 )2 .4H2 O ;
dimorphous with parahopeite; in minute grayish-white crystals with zinc
ores, esp. at Broken Hill, Zimbabwe.
A process for the recovery of copper in which a solution of cuprous
chloride in sodium or calcium chloride is used to dissolve copper
sulfides. The solution is then electrolyzed in tanks with diaphragms. The
anodes are impure copper; the cathodes, pure copper. Copper is deposited
from the cuprous chloride solution, and cupric chloride is regenerated.
Liddell
An electrically driven chain coal cutter designed and manufactured by
Mather and Platt in 1901 with provision for slewing the jib. A large
number of these machines were built. For many years the Hopkinson was the
only chain coal cutter built in the United Kingdom. Nelson
a. A vessel into which materials are fed, usually constructed in the form
of an inverted pyramid or cone terminating in an opening through which the
materials are discharged (not primarily intended for storage).
BS, 5
b. Surge bin placed at discharge end of intermittent transporting system
that handles dry ore or rock; used to smooth out and regulate delivery
from that point. A hopper car is one with bottom discharge gear and
insloping side walls. Pryor, 3
c. A storage bin or a funnel that is loaded from the top and discharges
through a door or chute in the bottom. Nichols, 1
d. A container or bin for broken ore. CTD
e. A place of deposit for coal or ore. Fay
A car for coal, gravel, etc., shaped like a hopper, with an opening to
discharge the contents. Standard, 2
A crystal with edges grown beyond face centers. CF:skeletal crystal
A hydraulic dredge that operates in cycles, alternately filling at a
dredge site and traveling to and from a disposal or offloading site.
In gold washing, gravel retained in the hopper of a cradle.
Pockets at the bottom of a breaker through which the processed coal falls
as it is loaded into railroad cars; also the cars. Korson
Grainer or solar salt produced in characteristic hollow-faced cubes by
surface evaporation. Kaufmann
Early type of pneumatic table used in ore treatment. Pryor, 3
A vessel for measuring ore. Standard, 2
A large bucket used in shaft sinking for hoisting men, rock, materials,
and tools. Since about 1955, hoppit sizes have increased to about 80 ft
3 (2.3 m3 ) and in some cases to 110 ft3 (2.5 m
3 ) and surface tipping facilities have been brought to a high
degree of efficiency to cope with large-diameter shafts and fast sinking
rates. See also:cactus grab
a. The drilling of a number of horizontal boreholes radiating outward from
a common center; a single drill site or drill setup. Long
b. See:horizontal-ring drilling
a. An interface indicative of a particular position in a stratigraphic
sequence. In practice it is commonly a distinctive, very thin bed or
marker. See also:marker bed
b. One of several lines or planes used as reference for observation and
measurement relative to a given location on the Earth's surface and
referred generally to a horizontal direction (Huschke, 1959); esp.
apparent horizon. The term is also frequently applied to artificial
horizon. AGI
c. One of the layers of the soil profile, distinguished principally by its
texture, color, structure, and chemical content, designated as A-horizon;
B-horizon; C-horizon. ASCE
d. An identifiable rock stratum regionally known to contain or be
associated with rock containing valuable minerals. CF:marker;
marker bed. Long
e. See:soil horizon
A system of mine development that is suitable for inclined, and perhaps
faulted, coal seams. Main stone headings are driven, at predetermined
levels, from the winding shaft to intersect and gain access to the seams
to be developed. The stone headings, or horizons, are from 100 to 200 yd
(91.44 to 182.88 m) vertically apart, depending on the seams available and
their inclination. The life of each horizon ranges from 10 to 30 years.
Connections between horizons at inby points are by staple shafts or
drivages in the coal. Also called horizontal mining; continental mining.
See also:lateral
A rotary drill, mechanically driven, for drilling horizontal blasting
holes in quarries and opencast pits. See also:auger;
vertical auger drill. Nelson