slip cases

Preferred label: 

Rectangular enclosures that are open on one edge for the insertion of a book. The open edge may either be at the top (top-loading slip cases) or on one side (side-loading slip cases). The earliest English examples of side-loading slip cases date from the last quarter of the eighteenth century and have flexible leather sides (collapsible side-loading slip-cases). Entirely rigid, leather-covered top loading examples (rigid top-loading slip-cases) were used for fancy pocket books and almanacs from at least the mid-eighteenth century and, covered in printed and decorated paper, were widely used for such books in the early nineteenth century. They were also commonly used for folding maps.

Etherington & Roberts (1982)

Roberts, Matt, Don Etherington, and Margaret R. Brown. 1982. Bookbinding and the conservation of books: a dictionary of descriptive terminology. Washington: Library of Congress.

Additional reference: 
http://cool.conservation-us.org/don/dt/dt3161.html
Broader concept: 
Broader partitive concept: 
Top concept: 
objects
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