sitor.
On the deftness with which this function is discharged depends almost
entirely the typographic excellence of the printed page. To justify is
to so increase the distance between the words by the introduction of
type-metal "spaces" as to enable the characters to exactly fill the
line. To make these spaces as nearly equal as possible is the aim of
every good printer, and in proportion as he succeeds in his endeavor
the printed page will please the eye and be free from those
irregularities of "white space," which detract from its legibility as
well as from its artistic appearance.

[Illustration: The Monotype Keyboard.]

[Illustration: The Monotype Caster.]

That the monotype should not only "justify" each line automatically,
but justify with a mathematical exactness impossible of attainment by
the more or less rough-and-ready methods of the most careful human
type-setter is at first thought a little bewildering. The fact
remains, however, that it does so, and another triumph is to be
recorded for man's "instruments of precision."

Monotype justification is effected as follows: an ingenious
registering device waits, as it were, on all the movements of the
operator, with the result that when he has approached as close to the
end of the line as he dare go, he has merely to glance at a
cylindrical dial in front of him. The pointer on this dial signifies
to him which of the "justifying keys" he must depress. He touches
them in accordance therewith, and the line is justified, or rather it
_will_ be justified when, as will be seen later on, the casting
machine takes up its part of the work. That is the outward
manifestation; it remains to be seen in what manner the machine
accomplishes its task. Firstly, the machine automatically notes the
exact width of the space left over at the line's end; then, also
automatically, it records the number of spaces between the words
already set which form the incompleted line; finally, it divides the
residuary space into as many parts as there are word-spaces, and
allots to each of these one of the parts. Thus if there is one-tenth
of an inch to spare at the end of the line and ten word-spaces, then
one-hundredth of an inch added to each of these spaces will justify
the line with mathematical accuracy. But the machine will do something
more wonderful than this. It will separately justify separate parts of
the same line. The utility of this is comprehended when it is pointed
out that