A fine-mesh gauze used as a sieve for clay. Crispin
In trigonometry, a law stating that in any triangle the square of one side
equals the sum of the squares of the two other sides minus twice the
product of these two other sides multiplied by the cosine of the included
angle. Jones, 2
In ore genesis, the statement that during the formation of ore by
replacement there is no change in rock volume or form.
Syn:Lindgren's volume law
See:apex law
The law, discovered by Sir Isaac Newton, that every particle of matter
attracts every other particle of matter, and the force between them is
proportional to the product of their masses divided by the square of their
distance apart. See also:gravitation; gravity. Standard, 2
The rate of a chemical reaction is directly proportional to the molecular
concentrations of the reacting substances.
A statement in dynamics that a body at rest remains at rest and a body in
motion remains in uniform motion in a straight line unless acted upon by
an external force. The acceleration of a body is directly proportional to
the applied force and is in the direction of the straight line in which
the force acts. For every force there is an equal and opposite force or
reaction. Webster 3rd
a. When a wave crosses a boundary, the wave normal changes direction in
such a manner that the sine of the angle of incidence between wave normal
and boundary normal divided by the velocity in the first medium equals the
angle of refraction divided by the velocity in the second medium.
AGI
b. Light, upon crossing a boundary between two transparent substances of
different optical densities, changes direction according to n2 /n
1 =sin i, where n1 is the refractive index (RI) for the
incident light ray making an angle i, and n2 is the RI for the
refracted light ray making an angle r with the boundary (n1 < n
2 ). Light rays refracted according to this law are called
"ordinary" rays. CF:critical angle; extraordinary ray; ordinary ray;
total reflection. Syn:Snell's law
In trigonometry, a law stating that in any triangle (either right or
oblique) the sides are proportional to the sines of their opposite angles.
Jones, 2
A general law upon which all geologic chronology is based: In any sequence
of sedimentary strata (or of extrusive igneous rocks) that have not been
overturned, the youngest stratum is at the top and the oldest at the base;
i.e., each bed is younger than the bed beneath, but older than the bed
above it. The law was first clearly stated by Steno (1669). AGI
An orthorhombic mineral, 4[CaAl2 Si2 O7 (OH)2
.H2 O] ; dimorphous with partheite; pale blue; Mohs hardness, 8; in
high-pressure, low-temperature schists.
See:vauquelinite
a. The direction, or length, of twist of the wires and strands in a rope.
Zern
b. The length of lay of wire rope is the distance parallel to the axis of
the rope in which a strand makes one complete turn about the axis of the
rope. The length of lay of the strand, similarly, is the distance in which
a wire makes one complete turn about the axis of the strand.
c. To close or withdraw from work; said of collieries. Standard, 2
d. The pitch or angle of the helix of the wires or strands of a rope,
usually expressed as the ratio of the diameter of the strand or rope to
the length required for one complete twist. Hunt
e. Prov. Eng. A standard of fineness for metals; possible from the Spanish
ley. Hess
a. Siding in otherwise single-track underground tramming road.
Pryor, 3
b. A term used for an underground siding at or near a shaft for storing
empty mine cars.
c. See:bank
a. A bed or stratum of rock.
b. One of a series of concentric zones or belts of the Earth, delineated
by seismic discontinuities. A classification of the interior of the Earth
that designates layers A to G from the surface inward. AGI
Thickness of the mixed surface layer of water. Hy
N. of Eng. Choked up with sediment or mud.
See:bedding
A dimensionless number, the value of which, taken in conjunction with
inclination, roughness, and whether the ventilation is ascensional or
descensional, determines the mixing and movement of combustible gases roof
layers. BS, 8
The formation of a layer of combustible gases at the roof of a mine
working and above the ventilating air current. BS, 8
Procedure for loading coal in railroad cars in horizontal layers.
Layer-loading is a simple and inexpensive method for smoothing out the
irregularities in coal and consists in shuttling two to six railroad cars,
hooked together, past the loading boom two or more at a time. This results
in a more uniform product. Mitchell