Plan (top), and three-quarter view (below), of a type case, lettered for a key. Engraving by Benard after L.-J. Goussier.

Licence: Public Domain Mark

Credit: Plan (top), and three-quarter view (below), of a type case, lettered for a key. Engraving by Benard after L.-J. Goussier. Wellcome Collection. Source: Wellcome Collection.