(metal) frame that is used to contain a printing forme
A single-page "forme" for printing the front page of the New Testament of the Christian Bible. The black frame surrounding it is the "'chase"', and the two objects each on the bottom and left side are the "quoins".
A chase is a heavy steel frame used to hold type in a letterpress.[1] Most of the space in the chase not occupied with type is filled with blocks of wood called furniture. The type and furniture are locked in place by quoins.[2] When a chase is locked up with type, furniture, and quoins, it is called a forme.
References
^Haynes, Roscoe E. (1922). American Printer and Lithographer. Moore Publishing Company. p. 143. Retrieved 18 June 2016. This brings the quoins at the top and right end of the chase and opposite the guides to which the sheets are fed.
