History of modern literature born. Mikhail Lermontov published "A Hero of Our Time" In 1841 Phillipe-Ignace François Aubert de Gaspé died. Edgar Allan Poe published two short stories: "A Descent into the Maelström" and "The Murders in the Rue Morgue". The latter introduced the fictional detective C. Auguste Dupin. Mikhail Lermontov was killed in a duel. In 1842, Nikolai Gogol published "Dead Souls". In 1843 the transatlantic author Henry James was born. Edgar Allan Poe published a poem: "Lenore" and four short stories: "The Gold-Bug", "The Black Cat", "The Tell-Tale Heart" and a C. Auguste Dupin short story called "The Mystery of Marie Roget".
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