a. A type of open flume with a contracted throat that causes a drop in the
hydraulic gradeline; used for measuring flow. Seelye, 1
b. A control flume that comprises a short constricted section followed by
one expanding to normal width. See also:control
A trademark for a form of the Venturi tube arranged to measure the flow of
a liquid in pipes. Small tubes are attached to the Venturi tube at the
throat and at the point where the liquid enters the converging entrance.
The difference in pressure heads is shown on some form of manometer and
from this difference and a knowledge of the diameters of the tubes, the
quantity of flow is determined. Webster 2nd
A closed conduit that is gradually contracted to a throat causing a
reduction of pressure head by which the velocity through the throat may be
determined. The contraction is generally followed, but not necessarily so,
by gradual enlargement to original size. Piezometers connected to the pipe
above the contracting section and at the throat indicate the drop in the
pressure head, which is an index of flow. Seelye, 1
A wire used by founders to make a hole in a sand mold for the escape of
air or gases. Standard, 2
Quartz containing needle-shaped crystals of rutile.
See also:Thetis hairstone; sagenitic quartz; sagenite.
A dark-green rock composed essentially of serpentine (hydrous magnesium
silicate) usually crisscrossed with white veinlets of marble. Found in
California, Georgia, Maryland, Massachusetts, New York, and Virginia. Used
as an ornamental stone. In commerce, it is often classed as a marble.
CCD, 2; Sanford
A green variety of elbaite (tourmaline).
The rotation of the plane of polarization per centimeter per unit magnetic
field in the Faraday effect. The value of the constant varies with
temperature and is approx. proportional to the square of the wavelength of
the light. CTD
A deep green, relatively soft metamorphic rock of green fuschite (chromian
muscovite) and clay with scattered grains of rutile; occurs in Transvaal
and Zimbabwe; is carved for ornamental use.
Talcose-dolomitic breccia rock from New Jersey. Schaller
a. A tool used in deep boring for detaching and bringing to the surface
portions of the wall of the borehole at any desired depth. Fay
b. In gas testing, an apparatus by which the amount of gas required to
produce a flame of a given size is measured; a gas verifier.
a. An orange-red garnet. Syn:vermilion
b. A reddish brown to orange-red gem variety of corundum.
c. An orange-red spinel. Syn:vermeille
Quartz in wormlike intergrowths with feldspar. See also:myrmekite
A monoclinic mineral, (Mg,Fe,Al)6 (Si,Al)8 O20 (OH)
4 .8H2 O ; mica group; basal cleavage; soft; pearly; a
hydrothermal or weathering alteration of biotite; expands 6 to 20 times by
thermal exfoliation; occurs in clay sizes in soils and as crystals and
megacrysts in ultramafic rocks; in Montana, North Carolina, South
Carolina, Wyoming, Virginia, Colorado, and South Africa. Syn:lernilite
a. A red pigment used in enormous quantities. Usually made from mercuric
sulfide, HgS, tinted with puranitraniline. Also spelled vermillion.
b. A bright-red pigment consisting of mercuric sulfide. Prepared
synthetically (as by the reaction of mercury, sulfur, and sodium
hydroxide), but formerly obtained from the mineral cinnabar. Color ranges
from crimson when coarse grained to nearly orange when finely divided.
Both spellings are correct. Webster 3rd
c. See:alpha mercuric sulfide; cinnabar; vermeil.
In the Lake Superior region, the lowest of the stratified schists; the
crystalline schists. Fay
Antlerite in aggregates of minute crystals or as pseudomorphs after
dolerphanite. See also:antlerite
A technique developed by Auguste V.L. Verneuil (1856-1913), French
mineralogist and chemist, for the manufacture of large crystals of
corundum and spinel in which powdered alumina with appropriate oxide
dopants is melted in an oxyhydrogen flame to produce boules of synthetic
gems. See also:boule