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rise and fall

A system of reduction of levels by working out the rise or fall of staff
readings from each level point to the one following it.
See also:collimation

rise face

A face advancing toward the rise of a coal seam. Briggs

rise heading

A heading driven to the rise in a long-way workings. See also:heading

riser

a. A shaft excavated from below upward. See also:raise; rise.
Fay
b. See:column pipe; rising main.

rising

a. An excavation carried from below upward; a rise or riser.
Standard, 2
b. Eng. The horizontal division of the stratum, from which the blocks of
stone are lifted; e.g., in the Portland quarries. Arkell

rising column

See:rising main

rising current

The direction in which a drill circulation fluid is flowing after it has
passed the bit and continues toward the collar of a borehole. Long

rising-head test

A soil permeability test in which the level of water in a borehole is
reduced and then the rate at which the water recovers is observed.
Mining

rising main

a. The length of steel piping that conveys the water from a pump to the
surface or to a higher pump in the shaft. The term rising main is
obsolete; delivery column preferred. Syn:delivery column
Nelson
b. See:column pipe

rising shaft

Excavating a shaft upwards from mine workings. See also:rise;
staple shaft. Nelson

rittingerite

See:xanthoconite

Rittinger's law

The energy required for reduction in particle size of a solid is directly
proportional to the increase in surface area. CF:Kick's law
CCD, 2

Rittinger table

A side-bump table with plane surface, actuated by a cam, spring, and
bumping post. Liddell

rivelaine

A pick with one or two points, formed of flat iron, used to undercut coal
by scraping instead of striking. Fay

river bar

A ridge or mound of boulders, gravel, sand, and mud found along or in a
stream channel at places where decrease in velocity causes deposition of
sediment.

river-bar placer

a. Gravel flats and terraces laid down by rivers when flowing at higher
levels than at present. The deposits are sometimes gold or tin-bearing.
See also:bench placer
b. A term used in Alaska for placers on gravel flats in or adjacent to the
beds of large streams.

river claim

A claim that includes the bed of a river.

river drift

The gravel deposits accumulated by a river in its torrential stages.

river flat

See:alluvial flat

river mining

Mining or excavating beds of existing rivers after deflecting their
course, or by dredging without changing the flow of water.

river pebble

Applied in Florida to a certain class of phosphatic pebbles, or
concretions, found in rivers as distinguished from land pebble phosphate.