Increase in bulk volume as a result of decrease in specific gravity.
Hardness of water that cannot be removed by boiling. Opposite of temporary
hardness.
Hard water that cannot be softened by boiling; water containing magnesium
sulfate or calcium sulfate. Bennett
Magnetic property of a substance maintained without external excitation.
Pryor, 3
A monument of a lasting character for marking a mining claim. It may be a
mountain, hill, ridge, hogback, butte, canyon, gulch, river, stream,
waterfall, cascade, lake, inlet, bay, arm of the sea, stake, post,
monument of stone or boulders, shafts, drifts, tunnels, open cuts, or
well-known adjoining patented claims. Fay
A permanent main pump is one on which a mine depends for the final
disposal of its drainage. As it is usually not moved during the life of
the mine, its location, installation, and design require careful
consideration. A permanent main pump may discharge on the surface, into an
underground sump, or into some other part of a mine.
The amount of permanent deformation of a material that has been stressed
beyond its elastic limit. AGI
After a shaft has been sunk to a certain depth, the final or permanent
lining is inserted. This may consist of: brick walling; concrete blocks
shaped to the curvature of the shaft; concrete lining put in liquid form
behind shuttering; brick coffering; and cast-iron tubbing. The permanent
lining is generally built up in sections, during which operation the
temporary lining (such as skeleton tubbing) is removed. Concrete is now
widely used as a permanent shaft support. See also:brick walling;
lining; steel rectangular shaft supports. Nelson
The completed assembly of rails, sleepers, fixings, and ballast forming
the finished track for a railway. Hammond
A salt of permanganic acid of the type, MnO4 ; dark purple; good
oxidizing agent; often used as a disinfectant. Enam. Dict.
a. The permeability (or perviousness) of rock is its capacity for
transmitting a fluid. Degree of permeability depends upon the size and
shape of the pores, the size and shape of their interconnections, and the
extent of the latter. It is measured by the rate at which a fluid of
standard viscosity can move a given distance through a given interval of
time. The unit of permeability is the darcy. See also:millidarcy;
coefficient of permeability. AGI
b. In geophysics, the ratio of the magnetic induction to the magnetic
intensity in the same region. In paramagnetic matter, the permeability is
nearly independent of the magnetic intensity; in a vacuum, it is strictly
so. But in ferromagnetic matter, the relationship is definite only under
fully specified conditions. AGI
c. See:coefficient of permeability
d. In magnetism, a general term used to express various relationships
between magnetic induction and magnetizing forces. These relationships are
either absolute permeability, which is the quotient of a change in
magnetic induction divided by the corresponding change in magnetizing
force, or specific (relative) permeability, the ratio of the absolute
permeability to the permeability of free space. ASM, 1
e. In founding, the characteristics of molding materials which permit
gases to pass through them. Permeability number is deteremined by a
standard test. ASM, 1
f. In powder metallurgy, a property measured as the rate of passage under
specified conditions of a liquid or gas through a compact. ASM, 1
Pertaining to a rock or soil having a texture that permits passage of
liquids or gases under the pressure ordinarily found in earth materials.
Syn:pervious
An instrument for measuring permeability. AGI
A process of fossilization wherein the original hard parts of an animal
have additional mineral material deposited in their pore spaces.
AGI
a. Means completely assembled and conforming in every respect with the
design formally approved by the U.S. Mine Safety and Health Administration
for use in gassy and dusty mines.
b. A machine or explosive is said to be permissible when it has been
approved by the U.S. Mine Safety and Health Administration for use
underground under prescribed conditions. All flameproof machinery is not
permissible, but all permissible machinery is flameproof.
c. A low-flame explosive used in gassy and dusty coal mines.
Nichols, 1
Any device, other than explosives, for breaking down coal that is approved
by the U.S. Mine Safety and Health Administration.
An electrical device for firing blasts, approved by the U.S. Mine Safety
and Health Administration.
Explosive that has been tested for safety in handling and approved for use
in mines by the U.S. Mine Safety and Health Administration.
An exposure limit published and enforced by the U.S. Occupational Safety
and Health Administration (OSHA) as a legal standard. NSC, 2
Any of several commercially available, fire-resistant fluids that are
water-in-oil emulsions and can be substituted for flammable hydraulic
fluids by users of large machinery, whether the equipment is operated
underground or on the surface.