the binding
is known to be entirely safe and firm.

The breaks between signatures are repaired and the old glue at these
points softened by means of bookbinders' paste. For this, a solid,
satisfactory and fairly elastic substitute can be made by mixing about
equal parts of good liquid glue and ordinary white library paste of the
kind which comes in tubes. With a long pin, slightly bent on the point,
this mixture is laid in the open crack between the signatures, care being
taken to distribute it evenly the whole length of the book and to
thoroughly cover the exposed inside of the back lining. An excess of paste
must be avoided, as it would spread out on the inside margins of the
leaves when the book is closed to dry. When all the broken places are
mended, the book is closed and placed under a slight pressure for a few
hours.

Where the book is bound with a "spring back," that is to say, with a back
which springs apart when the book is opened, leaving a space between the
outside back and the actual back of the signatures where they are
stitched, a further strengthening of the back may be desirable. This
strengthening can be obtained by "lining up" the inside back with a new
strip of paper.

To do this, cut a strip of medium weight Japan vellum--which is the best
paper for the purpose--a few inches more than twice the height of the book
and in width equal to the inside back. One end of this, with the corners
clipped so it will not catch, is inserted between the outside and inside
backs of the book and slipped through until it projects about an inch at
the bottom of the book. (Fig. A.) The part of the strip left exposed at
the top is then well coated on the inside face with the paste mentioned
above and pulled into the book, against the inside back or lining, by
means of the end projecting at the bottom. The surplus of the strip at top
and bottom is then cut off, two short slips of paper temporarily inserted
at top and bottom to prevent the new lining adhering to the outside back,
and a firm hand pressure applied all over the back to force the new lining
into close union with the old on the backs of the signatures. The book is
then set aside to dry, under a light pressure, after which the two slips
of paper inserted at top and bottom are pulled out.

[Illustration: Fig. A]

Any slight necessary exterior repairs should then be made--loose bits of
cloth or paper at worn corners or along the edges of the boards pasted