The Monk (1796)

by Matthew Lewis

The cover image on our version of The Monk is (in part) from Bosch’s “Garden of Earthly Delights” triptych.  Triptychs were made as altar pieces; the two side panels fold in to close over the center image.  The left image here portrays the Garden of Eden with Adam & Eve; the middle panel portrays a range of humans and animals in a variety of activities (check it out!); the right panel is a hellscape.  The image I’ve pasted below is the one that appears on the cover of the book (at least the left-hand side of the image does); you can find it in the lower right of the hellscape.

The Garden of Earthly Delights
Hieronymus Bosch, 1503-1504
Oil-on-wood triptych
220 cm × 389 cm (87 in × 153 in)
Museo del Prado, Madrid

Note that Lewis had nothing to do with this cover; Dover typically looks for images that are out of copyright to keep the publishing cheap.

There’s a good reproduction of the image here:
http://upload.wikimedia.org/wikipedia/commons/b/ba/Garden_delights.jpg

Wikipedia actually has a pretty thorough analysis of the painting and some of its imagery.