ble; you must not say, for instance, that the
captain controlled his men to present arms.

Such, abstractly stated, is the way to look up a word in the dictionary.
Let us now take a concrete illustration. Starting with the word
_tension_, let us ascertain what we can about it in the _Century
Dictionary and Cyclopedia_. Our first quest is the original meaning.
For this we consult the bracketed matter. There we meet the French,
Spanish, Portuguese, and Italian kinsmen of the word, and learn that they
are traceable to a common ancestor, the Latin _tensio(n)_, which
comes from the Latin verb _tendere_. The meaning of _tensio(n)_
is given as "stretching," that of _tendere_ as "stretch," "extend."
Thus we know of the original word that in form it closely resembles the
modern word, and that in meaning it involves the idea of stretching.

What is the central meaning of the word today? To acquaint ourselves with
this we must run through the definitions listed. Here (in condensed form)
they are. (1) The act of stretching. (2) In _mechanics_, stress or
the force by which something is pulled. (3) In _physics_, a
constrained condition of the particles of bodies. (4) In _statical
electricity_, surface-density. (5) Mental strain, stress, or
application. (6) A strained state of any kind, as political or social. (7)
An attachment to a sewing-machine for regulating the strain of the thread.
Now of these definitions (2), (3), (4), and (7) are too highly specialized
to conduct us, of themselves, into the highway of the word's meaning. They
bear out, however, the evidence of (1), (5), and (6), which have as their
core the idea of stretching, or of the strain which stretching produces.

We must now lay the original meaning alongside the central meaning today,
in order to draw our conclusions. We perceive that the two meanings
correspond. Yet by prying into them we make out one marked difference
between them. The original meaning is literal, the modern largely
figurative. To be sure, the figure has been so long used that it is now
scarcely felt as a figure; its force and definiteness have departed.
Consequently we may speak of being on a tension without having in mind at
all a comparison of our nervous system with a stretched garment, or with
an outreaching arm, or with a tightly strung musical instrument, or with a
taut rope.

What, then, is the net result of our investigation? Simply this, that
_tension_ means stretching, and that the st