A small, fairly light boring machine for shallow exploratory borings
underground. It drills in any direction (downwards, upwards, horizontally,
or obliquely) to depths of from 200 to 1,000 m, but usually only 50 m. It
uses coring or solid bits, with or without flushing and can be driven
either by hand, any oil engine, compressed air, or electricity.
Stoces
a. A steep precipitous point or eminence of rock, esp. one projecting from
the side of a mountain. Syn:craig
b. An obsolete term for a sharp, rough, detached, or projecting fragment
of rock. AGI
See:crag
a. A contrivance for holding parts of a frame in place during
construction. It usually consists of a steel bar along which slide two
brackets between which the work is fixed, one of the brackets being pegged
into a hole in the bar while the other is adjustable for position by means
of a screw. CTD
b. A locking bar of incorrodible metal used to bind together adjacent
stones in a course, and having bent ends, one of which is fastened into
each stone. Also called a cramp iron. CTD
An appliance for holding stones or other heavy objects that are to be
hoisted by crane. It consists of a pair of bars hinged together like
scissors, the points of which are bent inwards for gripping the load,
while the handles are connected by short lengths of chain to a common
hoist ring. CTD
a. A stonecutters' hammer for dressing ashlar. Its head is made up of
pointed steel bars of square section wedged in a slot in the end of the
iron handle. Standard, 2
b. To dress stone with a crandall. Standard, 2
a. A trigonal mineral, CaAl3 (PO4 )2 (OH)5 .H
2 O ; forms compact to cleavable or fibrous masses; formerly called
kalkwavellite.
b. The crandallite mineral group of trigonal phosphates and arsenates:
arsenocrandallite, arsenoflorencite-(Ce), arsenogorceixite,
arsenogoyazite, crandallite, dussertite, eylettersite, florencite-(Ce),
florencite-(La), florencite-(Nd), gorceixite, goyazite, lusungite,
philipsbornite, plumbogummite, waylandite, and zairite.
A long, light boom, usually of lattice construction. Nichols, 1
A pot or ladle supported by a chain from a crane; used for pouring molten
metals into molds. Fay
Wire rope consisting of 6 strands of 37 wires around a hemp center.
Hunt
A dam built of crates filled with stone.
a. A typically bowl-shaped or saucer-shaped pit or depression, generally
of considerable size and with steep inner slopes, formed on a surface or
in the ground by the explosive release of chemical or kinetic energy;
e.g., an impact crater or an explosion crater. AGI
b. A basinlike, rimmed structure that is usually at the summit of a
volcanic cone. It may be formed by collapse, by an explosive eruption, or
by the gradual accumulation of pyroclastic material into a surrounding
rim. CF:caldera
c. The formation of a large funnel-shaped cavity at the top of a well,
resulting from a blowout or occasionally from caving. Brantly, 1
d. In blasting, the funnel of rupture, which in bad rock may have very
steep sides and a relatively small volume of broken rock.
Syn:lunar crater
These cuts consist of one or several fully charged holes in which blasting
is carried out towards the face of the tunnel, i.e., toward a free surface
at right angles to the holes. These represent in principle a completely
new type of cut and make use of the crater effect that is obtained in
blasting a single hole at a free rock surface. The possibility of a
uniform enlargement can be counted on. This means that if the scale is
enlarged so that the diameter and depth of hole and length of the charge
are all doubled, e.g., a crater of double the depth will be obtained. The
number of holes can be increased instead of increasing the diameter of the
holes. Langefors
Crater theory defines an optimum burden or distance to a free face at
which a spherical explosive charge is buried and produces the greatest
volume of broken and excavatable rock. This distance is unique based on
rock type and explosive type. The theory also defines the critical depth
or spherical charge buried depth at which surface disturbance is barely
detectable, resulting in slight surface mounding and minor cracking.
See:shield
Of or pertaining to a craton.
A part of the Earth's crust that has attained stability, and has been
little deformed for a prolonged period. The term is now restricted to the
extensive central areas of the continents. AGI
A piece of a vein left uncut as a support. Arkell
One of a pair of an endless chain of plates driven by sprockets and used
instead of wheels, by certain power shovels, tractors, bulldozers,
drilling machines, etc., as a means of propulsion. Also any machine
mounted on such tracks.
An endless chain of plates used instead of wheels by certain power
shovels, continuous miners, etc. Nelson
A low passageway that only permits the passage of a person by crawling.
Syn:cat run