=Signature.= 1. The letter or figure on the first page of each folded sheet to ensure its proper place in the book when bound. 2. The folded sheet itself. Often called section.

=Sixteenmo.= A book printed on sheets folded into sixteen leaves.

Generally written 16mo.

=Size.= A preparation used in gilding and finishing.

=Skiving.= See Paring.

=Slips.= The pieces of bands or tapes projecting beyond the book after it is sewed.

=Smooth calf.= Plain, undecorated calf.

=Split boards.= 1. Boards split at the edge to admit slips and back-lining. 2. Boards made of two boards glued together, leaving a s.p.a.ce for insertion of slips and back-lining.

=Sprinkled calf.= Calf treated with acid so that it looks as if it had been sprinkled with dye.

=Sprinkled edges.= Edges which have been colored by shaking or spraying coloring matter on them.

=Squares.= The parts of the board projecting beyond the edges of the leaves of the book.

=Stabbing.= 1. Process of fastening together the signatures of a pamphlet with wire. 2. Piercing the boards for lacing-in.

=Stabbed.= A pamphlet is said to be stabbed when the signatures are held together by wire staples driven in vertically near the back and clinched on the other side.

=Stamping press.= See Blocking press.

=Stamps.= Blocks or dies used to impress designs upon leather.

=Standing press.= A large fixed press capable of holding many books.

=Start.= Sections which after cutting project beyond the others, are said to have started.

=Steamboating.= Cutting a number of books at the same time.

=St.i.tching.= Process of sewing signatures lengthwise with a sewing machine. _See also_ Saddle st.i.tching.

=Strawboard.= Very soft paper board easily broken or cut. Sometimes used in cheap work.

=Super.= A thin, coa.r.s.ely woven cotton cloth used for back-lining.

Called mull in England.

=Tacky.= Glue that is still sticky but not wet is tacky.

=Tail.= The bottom of the back of the book.

=Tar board.= See Boards.

=Thirty-twomo.= A book printed on sheets folded into thirty-two leaves.

Written 32mo.

=Three-quarters bound.= See Half-bound.

=Thrown out.= Folded maps or diagrams which are likely to be used a great deal can be mounted on cloth guards the width of the book. When opened they will be entirely outside the book and are said to be thrown out.

=Tight back.= A book on which the covering material is glued to the back. See page 44.

=t.i.tle.= s.p.a.ce between the bands upon which the t.i.tle is lettered.

=t.i.tle skiver.= Very thin skiver used as labels on which to gild lettering.

=t.i.tled.= See Pieced.

=Tooling.= The decoration of leather made by stamping designs in gold leaf upon it.

=Tools.= Bra.s.s stamps used in tooling.

=Top gilt.= Indicates that only the top edge of the book is gilded.

=Tree calf.= Imitation of the trunk and branches of a tree made with acid on the sides of a book bound in full calf.

=Trimmed.= 1. Books which have only the edges of projecting leaves, not the folds, cut off are said to be trimmed. 2. In library binding the term generally means that all edges have been trimmed even.

=Trindle.= A small tool used to take out the round of a book when it is being cut.

=Tub.= Stand supporting the lying press. Formerly a tub used to catch the paper cut from the edges.

=Turning up.= When books are cut in boards it is necessary to take the round out of the back. The process is a.s.sisted by the use of trindles and is called turning up.

=Twelvemo.= See Duodecimo.

=Twenty-fourmo.= A book having twenty-four leaves to a sheet.

=Two on.= See page 23.

=Tying up.= When leather covers are put on over raised bands it is necessary to tie them with twine so that the leather will stick to the sides of the bands.

=Uncut.= See Edges uncut.

=Unopened.= When the folds of signatures have not been cut the book is unopened.

=Varnish.= Bookbinder's varnish is used to give a gloss to leather. It is claimed that it acts as a preservative also.

=Verso.= Left hand page of an open book.

=Warp.= The threads running lengthwise in cloth.

=Waste papers.= The part of the end papers or fly leaves which in some kinds of work are removed when the end paper is pasted to the cover. The terms end papers, fly leaves and waste papers are used in different binderies with much the same meaning.

=Waterproof sheets.= Sheets of waterproof cardboard sometimes laid in or between books when pressing.