Tool the bookbinder uses to decorate and gild leather-bound books. It consists of a metal - often copper - elongated (approx. 10-12 cm long; approx. 1 cm wide) holder, fixed in a wooden handle. Blocks with letters can be placed in the holder, which can be clamped by a screw. After heating, the letters are stamped into the (gilded) leather, in order to obtain the desired word.
Some models are adjustable for different letter heights (1).
See also the bookbinder's pallet. [MOT]
(1) This is because letters for the letterpress are not always of the same height as handprint type (KIEL & LOBLER: 105).