n each side, and the free portions frayed out. If
proper sewing cord is used, this will be found to be very easily done,
if a binder's bodkin is first inserted between the two strands,
separating them, and then again in the centre of each separated strand
to still further straighten the fibres (see fig. 34).

The fraying out of the thick cord recommended for heavy books is a
more difficult operation, but with a little trouble the fibres of any
good cord can be frayed out. Vellum or tape bands will only require
cutting off, leaving about two inches free on each side. The free
parts of the bands are called slips.

[Illustration: FIG. 34.]

The book is now ready for glueing up. A piece of waste mill-board or
an old cloth cover is put on each side over the slips, and the book
knocked up squarely at the back and head. Then it is lowered into the
lying press and screwed up, leaving the back with the protecting
boards projecting about three-quarters of an inch. If the back has too
much swelling in it or is spongy, it is better to leave the slips on
one side free and to pull them as tight as possible while the book is
held in the press, or a knocking-down iron may be placed on one side
of the projecting back and the other side tapped with the backing
hammer to make the sections lie close to one another, and then the
slips pulled straight (fig. 35). The back must now be glued. The glue
for this operation must be hot, and not too thick. It is very
important that it should be worked well between the sections with the
brush, and it is well after it has been applied to rub the back with a
finger or folder to make quite sure that the glue goes between every
section for its entire length. If the book is too tightly screwed up
in the press, the glue is apt to remain too much on the surface; and
if not tightly enough, it may penetrate too deeply between the
sections. If the glue is thick, or stringy, it may be diluted with hot
water and the glue-brush rapidly spun round in the glue-pot to break
it up and to make it work freely.

[Illustration: FIG. 35.]

Very great care is needed to see that the head of a previously trimmed
book is knocked up exactly square before the back is glued, for if it
is not, it will be very difficult to get it even afterwards.

ROUNDING AND BACKING

The amount of rounding on the back of a book should be determined by
the necessities of the case; that is to say, a back