Quartz.
A mineral, silica, SiO2. It has recently been used by C. V. Boys and
since by others in the making of filaments for torsion suspensions. The
mineral is melted, while attached to an arrow or other projectile. It is
touched to another piece of quartz or some substance to which it adheres
and the arrow is fired off from the bow. A very fine filament of
surpassingly good qualities for galvanometer suspension filaments is
produced.
As a dielectric it is remarkable in possessing but one-ninth the
residual capacity of glass.
Quicking.
The amalgamating of a surface of a metallic object before silver
plating. It secures better adhesion of the deposit. It is executed by
dipping the article into a solution of a salt of mercury. A solution of
mercuric nitrate 1 part, in water 100 parts, both by weight, is used.
R.
(a) Abbreviation and symbol for Reamur, as 10º R., meaning 10º by the
Reamur thermometer. (See Reamur Scale.)
(b) Symbol for resistance, as in the expression of Ohm's Law C=E/R.
(rho, Greek r) Symbol for specific resistance.
Racing of Motors.
The rapid acceleration of speed of a motor when the load upon it is
removed. It is quickly checked by counter-electro-motive force. (See
Motor, Electric.)
Radian.
The angle whose arc is equal in length to the radius; the unit angle.
Radiant Energy.
Energy, generally existing in the luminiferous ether, kinetic and
exercised in wave transmission, and rendered sensible by conversion of
its energy into some other form of energy, such as thermal energy.
If the ether waves are sufficiently short and not too short, they
directly affect the optic nerve and are known as light waves; they may
be so short as to be inappreciable by the eye, yet possess the power of
determining chemical change, when they are known as actinic waves; they
may be also so long as to be inappreciable by the eye, when they may be
heat-producing waves, or obscure waves.
Other forms of energy may be radiant, as sound energy dispersed by the
air, and gravitational energy, whose connection with the ether has not
yet been demonstrated.
Radiation.
The traveling or motion of ether waves through space.
[Transcriber's note: The modern term corresponding to this definition is
photons. The modern concept of radiation also includes particles--
neutrons, protons, alpha (helium) and beta (electrons) rays and other
exotic items.]
Radicals.
A portion of a molecule, possessing a free bond and hence free to
combine directly. A radical never can exist alone, but is only
hypothetical. An atom is a simple radical, an unsaturated group of atoms
is a compound radical.