es on account of some difficulty,
or problem, presented to the mind, as for example:

What is the effect of heat upon air?
Will glass conduct electricity?
Why do certain bodies refract light?

To satisfy itself upon the problem, the mind appeals to actual
experience either by ordinary observation or through experimentation.
These observations or experiments, which necessarily deal with
particular instances, are supposed to provide a number of particular
judgments, by examining which a satisfactory conclusion is ultimately
reached.

=Example of Induction.=--As an example of induction, may be taken the
solution of such a problem as, "Does air exert pressure?" To meet this
hypothesis we must evidently do more than merely abstract the manifest
properties of an object, as is done in ordinary conception, or appeal
directly to some known general principle, as is done in deduction. The
work of induction demands rather to examine the two at present known but
disconnected things, _air_ and _pressure_, and by scientific observation
seek to discover a relation between them. For this purpose the
investigator may place a card over a glass filled with water, and on
inverting it find that the card is held to the glass. Taking a glass
tube and putting one end in water, he may place his finger over the
other end and, on raising the tube, find that water remains in the tube.
Soaking a heavy piece of leather in water and pressing it upon the
smooth surface of a stone or other object, he finds the stone can be
lifted by means of the leather. Reflecting upon each of these
circumstances the mind comes to the following conclusions:

Air pressure holds this card to the glass,
Air pressure keeps the water in the tube,
Air pressure holds together the leather and the stone,
.'. Air exerts pressure.

=How Distinguished from, A. Deduction, and B. Conception.=--Such a
process as the above constitutes a process of reasoning, first, because
the conclusion gives a new affirmation, or judgment, "Air exerts
pressure," and secondly, because the judgment is supposed to be arrived
at by comparing other judgments. As a process of reasoning, however, it
differs from deduction in that the final judgment is a general judgment,
or truth, which seems to be based upon a number of particular judgments
obtained from actual experience, while in deduction the conclusion was
particular and the major premise general. It is for this reason t