FW Bessel (1825): The calculation of longitude and latitude from geodesic measurements

First of all, it should be no surprise that a paper on this subject appeared in an astronomical journal. At the time, the disciplines of astronomy, navigation, and surveying were inextricably linked ¿ the methods and, in many cases, the practitioners (in particular, Bessel) were the same. Prior to Bessel¿s paper, the solution of the geodesic problem had been the subject of several studies by Clairaut, Euler, du S´ejour, Legendre,Oriani, and others. The interest in the subject was twofold. It combined several new fields of mathematics: the calculus of variations, the theory of elliptic functions, and the differential geometry of curved surfaces. It also addressed very practical needs: the determination of the figure of the earth, the requirements of large scale surveys, and the construction of map projections.With the papers of Legendre and of Oriani in 1806, the framework for the mathematical solution for an ellipsoid of revolution had been established.