Occult detective fiction Occult detective fiction Occult detective fiction combines the tropes of detective fiction with those of supernatural horror fiction. Unlike the traditional detective, the occult detective is employed in cases involving ghosts, curses, and other supernatural elements. Some occult detectives are portrayed as being themselves psychic or in possession of other paranormal powers. Edgar Allan Poe wrote three stories featuring a detective involved with the occult named C. Auguste Dupin, starting with "The Murders in the Rue Morgue" which was first published in 1841. Fitz James O’Brien’s character Harry Escott is another contender for first occult detective in fiction. A specialist
Dupin cyclide of Dupin cyclides is invariant under the larger group of all Lie sphere transformations; any two Dupin cyclides are Lie-equivalent. They form (in some sense) the simplest class of Lie-invariant surfaces after the spheres, and are therefore particularly significant in Lie sphere geometry. The definition also means that a Dupin cyclide is the envelope of the one-parameter family of spheres tangent to three given mutually tangent spheres. It follows that it is tangent to infinitely many Soddy's hexlet configurations of spheres. A further special property of a cyclide is: An elliptic cyclide can be represented parametrically by the following formulas