KEES, F. K. [FRIEDRICH KÖES].

Ratio Complanandi Superficies Curvas Corporum quorumlibet Geometricorum.

Leipzig, Grosse & Gleditsch, 1729. 4to. In: "Actorum Eruditorum Supplementa Tomus IX". The entire volume offered in contemporary full vellum. Hand written title on spine. A yellow label pasted on to top of spine. Two small stamp to title-page and free front end-paper. Library label to pasted down front free end-paper. As usual with various browning to leaves and plates. Pp. 45-50. [Entire volume: (2), 509, (24), + two engraved plates.].

First publication of perhaps the first attempt to create a formula describing curvature or curved surfaces, thus making it one of the most important Danish contributions to mathematical history. The result is given in a double-integral.

Euler established the theory of surfaces in his 'Recherches sur la courbure des surfaces', 1767. Gauss later took a fundamentally different approach to the study of surfaces; in contrast to Euler he represented the points of a surface in terms of two external parameters. Gauss then derived his own notions of the fundamental quantities of surfaces, e.g. arc length, angle between curves, and curvature.

Niels Nielsen "Matematikeni Danmark 1528-1800", Koës No. 9. Observator i Berlin, privatdocent i Kiel, underviste artilleriofficererne i Rendsborg, blev 1721 ordinær professor i matematik ved Kiels Universitet.

(Pihl, Københavns Universitet 1479-1979, Bind XII, P. 146)

Order-nr.: 45324