Glossary of Terms

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All along
Refers to a method of sewing signatures through the fold by hand. Sewing thread travels in and out of the fold of one signature, from kettle stitch to kettle stitch, then passes to the next signature and travels in and out of the fold from kettle stitch to kettle stitch; so that each pass of thread along the length of the spine attaches one signature to the text block. When sewing “two-on,” the thread travels in and out of the fold of one signature, then in and out of the fold of another, alternating from one signature to the other as it passes from kettle stitch to kettle stitchóso that each pass of thread along the length of the spine attaches two signatures to the text block. Sewing all along is the stronger method and should be used unless the text block has many thin signatures, in which case sewing all along would result in an excessive buildup of thread in the spine. Library binders must sew two-on only in rare cases. Back to top
 
Alkaline buffered paper
Paper containing an alkaline compound (calcium carbonate, for example) at a level sufficient to neutralize acid that might, in the future, be generated through aging of the paper or from atmospheric pollution. Back to top
 
Artifactual value
A volume that has artifactual value is important as a physical object. Often artifactual value is obvious (the manuscripts of a well-known poet are artifacts), but sometimes it is less so. A plain volume may be among the first manufactured by machine in the 1820s in England, for example; may have a signed, early machine-stamped binding, important hand binding, or hand-colored illustrations,; or may be a first edition or special edition of an important work, for example. Anything that is done to change such artifacts reduces their value. Back to top
 
Back/Backing (also see Round/Rounding and illustration)
The process of dispersing the swelling of the spine of a rounded text block and shaping it into a shoulder on each side of the spine of a text block. Backing accommodates the thickness of the boards, and provides a hinge along which they can swing freely. Backing also helps to prevent the spine of the text block from collapsing into a concave shape over time. Back to top
 
Binding Edge
The edge of a text block along which the leaves of a text block are attached by sewing, adhesive binding or another method. Back to top
 
Binding Margin (inner margin, gutter margin, back margin)
The margin along which the leaves of a text block are attached.The distance between the binding edge of a printed page and the printed area. Back to top
 
Book Block
The text block plus the endpapers and other materials added by the binder before casing-in to a hard cover. Back to top
 
Brittle paper
Paper that will break when it is folded or crumpled. (The main causes of brittleness are acidity introduced during the paper manufacturing process and storage in polluted air.) Back to top
 
Building-in Machine
A hydraulic or pneumatic machine used to duplicate the action of a hand book press. The cased-in text block is placed between the platens of the machine, which then close and exert great pressure. Heated jaws compress the case along its hinges to form tight front and back joints. Back to top
 
Case (see illustration)
A book cover consisting of two boards and an inlay covered with paper, cloth, or some other covering material. The case is made separately from the text block and is later attached to it in a step called casing-in. A cased-in book is often referred to as a hard cover book. Back to top
 
Casing-in
The process of applying adhesive to the outside endpapers of a text block and fitting the text block into its case. Back to top
 
Cloth/cloth-bound
The fabric used for book covers; a term used indiscriminately for any cloth-bound volume. Back to top
 
Collation
Collation library binding, the process of checking books and periodicals for completeness, physical characteristics, margin width, condition of paper, and overall suitability for binding. Also, preparation and arrangement of material in proper sequence for binding. Back to top
 
Flat Back (square back)
A text block that has not been rounded and backed. Back to top
 
Fore Edge
The edge of a leaf or a board opposite from, and parallel to, its binding edge (i.e., opposite from its spine edge). Fore edge is also used in a more general way to refer to any part of a volume opposite from, and parallel to, its spine. Back to top
 
Grain Direction
The direction in which the majority of the fibers in a piece of paper or board are aligned; and the direction in which the warp threads run in cloth. Grain direction in all man-made materials used in bookbinding should run parallel to the spine of a volume. Back to top
 
Guard
A thin strip of cloth or paper used as a hinge for a map, illustration or a single sheet. Back to top
 
Hard cover
The cover of a book produced from a flexible material, usually cloth or paper supported by rigid boards. Back to top
 
Head
The top edge of a leaf, board, or bound volume, opposite from the surface on which the volume rests when it is shelved upright. Back to top
 
Hinge In
To hinge in a leaf or a group of leaves that are attached to one another, a paper or cloth strip is adhered along the binding edge of the leaf (or leaves) so that the strip extends beyond the binding edge. This assembly can then be “hinged” into a text block by pasting up the part of the paper or cloth strip that extends beyond the leaf (or leaves), and adhering the strip to the binding edge of a leaf in the text block. Back to top
 
Inlay (back strip)
A heavy-weight but flexible paper strip used to stiffen the spine of a case, centrally placed between two cover boards. Back to top
 
Joint
The grooves that run head to tail on the outside of the case, front and back, along which the boards hinge when they open. Back to top
 
Kettle Stitch
Kettle stitches are the stitches closest to the head and tail of each signature of a text block that has been sewn through the fold by hand. The kettle stitches lock the sewing thread after each complete pass of the thread along the spine of the text block, and link each signature to the one sewn on previously. Back to top
 
Leaf
A leaf is a single sheet of paper, or one half of a folded sheet of paper. Each side of the leaf is a page. Leaves can be printed or blank. Back to top
 
Leaf Attachment
The means by which the leaves of a text block are attached, one to another. Leaves are most often attached along their binding edges by means of thread, adhesive, or staples. The latter method of leaf attachment does not comply with the ANSI/NISO/LBI Standard Back to top
 
Lining (super, mull, crash, and gauze)
Cotton, muslin, gauze, crash, paper and other materials used to reinforce spines of library bound books. It provides the means for a firm connection between text block and cover and gives shape and firmness to the binding. Back to top
 
Lock Stitch
Lock stitches are the type made by household sewing machines, although the machines used by library binders are often larger. Stitches are formed by a primary thread that runs along the top surface of the text block being sewn; and a bobbin thread that runs along the bottom surface, and locks with the top thread at regular intervals. Back to top

Mill
The spines of books can be cut away on a milling machine to prepare them for double-fan adhesive binding or oversewing. The machine clamps the text block, spine down, and moves it over a series of rotating blades that cut away approximately 1/8 inch of the binding margin, thus removing old adhesive, thread, staples, and/or folds of signatures. After milling, a text block is comprised of loose leaves. Back to top
 
Notch/Notching
The spines of text blocks can be notched by machine prior to double-fan adhesive binding. Notches are parallel grooves cut into the spine perpendicular to the binding edge. The depth of the grooves and the distance between them can be adjusted to suit the size and weight of the text block. Notching increases the amount of surface area on the spine that comes in contact with the adhesive and increases the strength of double- fan adhesive bindings. Back to top
 
Overhang
The covering material that extends beyond the edges of the boards and inlay before turning-in. The overhang becomes the turn-in. Back to top
 
Round/Rounding (see Back/Backing)
The mechanical or manual manipulation of the spine of a text block into a convex shape (and the consequent manipulation of the fore edge into a concave shape). Rounding usually precedes backing. Rounding and backing help distribute the swell that naturally occurs with sewing and adhesive binding. Back to top
 
Sewing on Tapes
Signatures can be hand sewn through the fold onto cloth tapes. Holes can be punched through the folds of each signature; or saw cuts can be made across the spine of the text block, perpendicular to the binding edge, to create holes through which the sewing needle can pass. Signatures are sewn onto tapes by passing the sewing needle into the signature, through the fold, at the kettle stitch; out and around a tape; and back into the signature, through the fold. This process is repeated along the length of the signature — the number of times depending on the number of tapes used. The tapes link the signatures, one to another, across the spine. Back to top
 
Shoulder (joint, ridge, flange)
The shoulder is formed when a text block is backed. During this process the outermost leaves on each side of the text block are bent outward at a 45 degree angle along the binding edge, to accommodate the boards and to allow them to hinge freely. The ridge that is thus formed on either side of the spine is the shoulder.
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Signature (section or gathering)
A signature consists of two or morea sheets of paper, stacked and folded one, two, three or four (and rarely five) times to make a section. Signatures are commonly eight, sixteen or thirty-two pages.as a group. One issue of The New Library Scene is a signature. Back to top
 
Spine (backbone)
that is, the surface opposite the fore edge. It is the part of a bound text block between the two cover boards on which the lettering appears. Back to top
 
Spine stamplettering pattern
A stamplettering pattern refers to the arrangement of letters, numbers, and punctuation on the spine of a case. The color of stamping foil is also part of the stamplettering pattern. Back to top
 
Squares
The edges of the case that extend beyond the text block at the head, tail, and fore edge, and protect it.
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Surface finish of paper
Surface finish is the quality of the surface of a sheet of paper. Paper can be rough or smooth, absorbent or repellent, shiny or dull. Back to top
 
Tail
The bottom edge of a leaf, board, or bound volume; that is, the surface on which a volume rests when shelved upright. Back to top
 
Text Block
The leaves of a volume after they have been bound together. A gathering of printed or written leaves that may be or have been bound, excluding all paper to be added by the bookbinder such as the endpapers. Back to top
 
Tip In
A thin line of adhesive is applied along the edge of a leaf (usually along the binding edge), and the leaf is tipped onto another leaf (usually at the binding edge). The openability of a tipped-in leaf will be somewhat restricted.
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Turn-in
That part of the covering material that is turned over the outer edges of the boards and inlay, and onto their inner surfaces, in the process of making a case. The turn-in protects the boards and inlay from delamination and wear. Most of the turn-in will be covered by the text block after casing-in. Back to top
 
Whip Stitch (overcasting)
In preparation for whip stitching, holes are usually punched along the binding edge of a text block. Sewing thread passes into the top and out the bottom of each hole in succession to attach the leaves. Library binders whip stitch new endpapers to oversewn and side sewn text blocks in preparation for recasing. Back to top