The Exploits of Chevalier Dupin the introduction by Ellery Queen, and the non-fiction piece on Dupin by Harrison. "The Exploits of Chevalier Dupin" contains the following tales: The Exploits of Chevalier Dupin The Exploits of Chevalier Dupin is a collection of detective short stories by author Michael Harrison. It was released in 1968 by Mycroft & Moran in an edition of 1,917 copies. The stories are pastiches of the C. Auguste Dupin stories of Edgar Allan Poe. The stories were first published in Ellery Queen's Mystery Magazine. There is an expanded UK edition by a different publisher which adds a further five stories This appeared
Dupin cyclide Dupin cyclide In mathematics, a Dupin cyclide or cyclide of Dupin is any geometric inversion of a standard torus, cylinder or double cone. In particular, these latter are themselves examples of Dupin cyclides. They were discovered by (and named after) Charles Dupin in his 1803 dissertation under Gaspard Monge. The key property of a Dupin cyclide is that it is a channel surface (envelope of a one-parameter family of spheres) in two different ways. This property means that Dupin cyclides are natural objects in Lie sphere geometry. Dupin cyclides are often simply known as "cyclides", but the latter term is