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The Collaborative International Dictionary of English v.0.48 (gcide)

Induction \In*duc"tion\, n. [L. inductio: cf. F. induction. See
{Induct}.]
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1. The act or process of inducting or bringing in;
introduction; entrance; beginning; commencement.
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I know not you; nor am I well pleased to make this
time, as the affair now stands, the induction of
your acquaintance. --Beau. & Fl.
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These promises are fair, the parties sure,
And our induction dull of prosperous hope. --Shak.
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2. An introduction or introductory scene, as to a play; a
preface; a prologue. [Obs.]
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This is but an induction: I will draw
The curtains of the tragedy hereafter. --Massinger.
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3. (Philos.) The act or process of reasoning from a part to a
whole, from particulars to generals, or from the
individual to the universal; also, the result or inference
so reached.
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Induction is an inference drawn from all the
particulars. --Sir W.
Hamilton.
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Induction is the process by which we conclude that
what is true of certain individuals of a class, is
true of the whole class, or that what is true at
certain times will be true in similar circumstances
at all times. --J. S. Mill.
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4. The introduction of a clergyman into a benefice, or of an
official into a office, with appropriate acts or
ceremonies; the giving actual possession of an
ecclesiastical living or its temporalities.
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5. (Math.) A process of demonstration in which a general
truth is gathered from an examination of particular cases,
one of which is known to be true, the examination being so
conducted that each case is made to depend on the
preceding one; -- called also {successive induction}.
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6. (Physics) The property by which one body, having
electrical or magnetic polarity, causes or induces it in
another body without direct contact; an impress of
electrical or magnetic force or condition from one body on
another without actual contact.
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{Electro-dynamic induction}, the action by which a variable
or interrupted current of electricity excites another
current in a neighboring conductor forming a closed
circuit.

{Electro-magnetic induction}, the influence by which an
electric current produces magnetic polarity in certain
bodies near or around which it passes.

{Electro-static induction}, the action by which a body
possessing a charge of statical electricity develops a
charge of statical electricity of the opposite character
in a neighboring body.

{Induction coil}, an apparatus producing induced currents of
great intensity. It consists of a coil or helix of stout
insulated copper wire, surrounded by another coil of very
fine insulated wire, in which a momentary current is
induced, when a current (as from a voltaic battery),
passing through the inner coil, is made, broken, or
varied. The inner coil has within it a core of soft iron,
and is connected at its terminals with a condenser; --
called also {inductorium}, and {Ruhmkorff's coil}.

{Induction pipe}, {Induction port}, or {Induction valve}, a
pipe, passageway, or valve, for leading or admitting a
fluid to a receiver, as steam to an engine cylinder, or
water to a pump.

{Magnetic induction}, the action by which magnetic polarity
is developed in a body susceptible to magnetic effects
when brought under the influence of a magnet.

{Magneto-electric induction}, the influence by which a magnet
excites electric currents in closed circuits.
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{Logical induction}, (Philos.), an act or method of reasoning
from all the parts separately to the whole which they
constitute, or into which they may be united collectively;
the operation of discovering and proving general
propositions; the scientific method.

{Philosophical induction}, the inference, or the act of
inferring, that what has been observed or established in
respect to a part, individual, or species, may, on the
ground of analogy, be affirmed or received of the whole to
which it belongs. This last is the inductive method of
Bacon. It ascends from the parts to the whole, and forms,
from the general analogy of nature, or special
presumptions in the case, conclusions which have greater
or less degrees of force, and which may be strengthened or
weakened by subsequent experience and experiment. It
relates to actual existences, as in physical science or
the concerns of life. Logical induction is founded on the
necessary laws of thought; philosophical induction, on the
interpretation of the indications or analogy of nature.
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Syn: Deduction.

Usage: {Induction}, {Deduction}. In induction we observe a
sufficient number of individual facts, and, on the
ground of analogy, extend what is true of them to
others of the same class, thus arriving at general
principles or laws. This is the kind of reasoning in
physical science. In deduction we begin with a general
truth, which is already proven or provisionally
assumed, and seek to connect it with some particular
case by means of a middle term, or class of objects,
known to be equally connected with both. Thus, we
bring down the general into the particular, affirming
of the latter the distinctive qualities of the former.
This is the syllogistic method. By induction Franklin
established the identity of lightning and electricity;
by deduction he inferred that dwellings might be
protected by lightning rods.
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Magnetic \Mag*net"ic\, Magnetical \Mag*net"ic*al\, a. [L.
magneticus: cf. F. magn['e]tique.]
1. Pertaining to the magnet; possessing the properties of the
magnet, or corresponding properties; as, a magnetic bar of
iron; a magnetic needle.
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2. Of or pertaining to, or characterized by, the earth's
magnetism; as, the magnetic north; the magnetic meridian.
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3. Capable of becoming a magnet; susceptible to magnetism;
as, the magnetic metals.
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4. Endowed with extraordinary personal power to excite the
feelings and to win the affections; attractive; inducing
attachment.
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She that had all magnetic force alone. --Donne.
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5. Having, susceptible to, or induced by, animal magnetism,
so called; hypnotic; as, a magnetic sleep. See
{Magnetism}. [Archaic]
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{Magnetic amplitude}, {attraction}, {dip}, {induction}, etc.
See under {Amplitude}, {Attraction}, etc.

{Magnetic battery}, a combination of bar or horseshoe magnets
with the like poles adjacent, so as to act together with
great power.

{Magnetic compensator}, a contrivance connected with a ship's
compass for compensating or neutralizing the effect of the
iron of the ship upon the needle.

{Magnetic curves}, curves indicating lines of magnetic force,
as in the arrangement of iron filings between the poles of
a powerful magnet.

{Magnetic elements}.
(a) (Chem. Physics) Those elements, as iron, nickel,
cobalt, chromium, manganese, etc., which are capable
or becoming magnetic.
(b) (Physics) In respect to terrestrial magnetism, the
declination, inclination, and intensity.
(c) See under {Element}.

{Magnetic fluid}, the hypothetical fluid whose existence was
formerly assumed in the explanations of the phenomena of
magnetism; -- no longer considered a meaningful concept.


{Magnetic iron}, or {Magnetic iron ore}. (Min.) Same as
{Magnetite}.

{Magnetic needle}, a slender bar of steel, magnetized and
suspended at its center on a sharp-pointed pivot, or by a
delicate fiber, so that it may take freely the direction
of the magnetic meridian. It constitutes the essential
part of a compass, such as the mariner's and the
surveyor's.

{Magnetic poles}, the two points in the opposite polar
regions of the earth at which the direction of the dipping
needle is vertical.

{Magnetic pyrites}. See {Pyrrhotite}.

{Magnetic storm} (Terrestrial Physics), a disturbance of the
earth's magnetic force characterized by great and sudden
changes.

{magnetic tape} (Electronics), a ribbon of plastic material
to which is affixed a thin layer of powder of a material
which can be magnetized, such as ferrite. Such tapes are
used in various electronic devices to record fluctuating
voltages, which can be used to represent sounds, images,
or binary data. Devices such as audio casette recorders,
videocasette recorders, and computer data storage devices
use magnetic tape as an inexpensive medium to store data.
Different magnetically susceptible materials are used in
such tapes.

{Magnetic telegraph}, a telegraph acting by means of a
magnet. See {Telegraph}.
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