perversions.

Human clothing is for protection and adornment. That of a book involves
two other demands mutually so contradictory that bookbinding has always
offered a most attractive challenge to the skill of the handicraftsman.
The first demand is that the book when closed shall form a well-squared
and virtually solid block, like the rectangle of wood from which its
first predecessors were split, and shall be able to stand alone,
unsupported. The second demand is that this same object, when open,
shall lie flat at any point and display all its leaves in turn as fully,
and far more conveniently, than if they had never been fastened
together. Whatever may be true of other clothing, it is eminently true
of a book's that the part which really counts is the part which is never
seen. Only the ornamental portion of a book's covering is exposed. The
portions which protect the book and render it at once firm and flexible
are out of sight and unheeded by the ordinary reader. Hence the
existence of so much bookbinding that is apparently good and essentially
bad, and hence the perpetual timeliness of attempts like that of the
present chapter, to point out what binding is and should be. The
processes in bookbinding by which its different ends of utility and
ornament are achieved are known under the two heads of Forwarding and
Finishing.

Forwarding includes many processes, literally "all but the finishing."
It is to forwarding that a book owes its shapeliness, its firmness, its
flexibility, and its durability. Forwarding takes the unfolded and
unarranged sheets as delivered by the printer and transforms them into a
book complete in all but its outermost covering of cloth or leather. The
first process is to fold the sheets and reduce their strange medley of
page numbers to an orderly succession. This is assuming that there is a
whole edition to be bound. If it consists of a thousand copies, then
there will be a certain number of piles of folded sheets, each
containing a thousand copies of the same pages printed in groups, let us
say, of sixteen each. These groups of pages are called sections or
signatures. They are now rearranged, or gathered, into a thousand piles,
each containing the signatures that belong to one book. The edition is
thus separated into its thousand books, which the collator goes over to
see that each is perfect. Let us follow the fortunes of a single one. It
is not much of a book to look at, being rather a pu