The Gold-Bug given. Nevertheless, the Legrand character is often compared to Poe's fictional detective C. Auguste Dupin due to his use of "ratiocination". "Ratiocination", a term Poe used to describe Dupin's method, is the process by which Dupin detects what others have not seen or what others have deemed unimportant. Poe originally sold "The Gold-Bug" to George Rex Graham for "Graham's Magazine" for $52 but asked for it back when he heard about a writing contest sponsored by Philadelphia's "Dollar Newspaper". Incidentally, Poe did not return the money to Graham and instead offered to make it up to him with reviews he
Dupin indicatrix Dupin indicatrix In differential geometry, the Dupin indicatrix is a method for characterising the local shape of a surface. Draw a plane parallel to the tangent plane and a small distance away from it. Consider the intersection of the surface with this plane. The shape of the intersection is related to the Gaussian curvature. The Dupin indicatrix is the result of the limiting process as the plane approaches the tangent plane. The indicatrix was invented by Charles Dupin. For elliptical points where the Gaussian curvature is positive the intersection will either be empty or form a closed curve. In the