book-drill
1. A linen cloth used to reinforce endpapers. This
type of reinforcement is sometimes required
because opening the cover, particularly in the
case of side sewn books which have little
flexibility, strains the sewing and will
eventually cause the endpaper to break away unless
it is reinforced. 2. A high-speed electric drill
used for producing holes of a very small diameter
through the paper of books to be overcast but not
resewn. A similar drill, usually in a press, is
used to drill holes completely through the leaves
of a book that is to be side sewn.