One of the most beautiful frontispiece portraits ever published is this mezzotint made by Prince Rupert, Ruprecht of Pfalz (1619-1682) for John Evelyn's history of engraving techniques:
John Evelyn (1620-1706). Sculptura, or, The History, and Art of Chalcography and Engraving in Copper (London: printed by J.C. for G. Beedle, and T. Collins, at the Middle-Temple Gate, and J. Crook in St. Pauls Church-yard, 1662.) "Elmer Adler. Princeton MCM-XLII"--Written in pencil in Elmer Adler's hand on verso of front free endpaper. Graphic Arts Collection (GAX) NE1760 .E94
According to David Rodgers, "Sculptura was probably the direct result of Evelyn's introduction by Prince Rupert of the Rhine in 1661 to the technique of mezzotint engraving. The book contains a plate engraved by Rupert of the Head of the Executioner of John the Baptist from a painting (Munich, Alte Pin.) then thought to be by Jusepe de Ribera. This plate is now the only virtue of Sculptura, in which the account both of the history and the practice of printmaking is unreliable and the style discursive and inelegant."
The print in our book is a reduced version of a huge mezzotint, one copy of which is in the British Museum. Here's their wonderful description: http://www.britishmuseum.org/explore/highlights/highlight_objects/pd/p/prince_rupert_ruprecht_of_pfa.aspx