 Carl Friedrich Gauss became the first director of the Observatory, and lived there between 1815 and 1855.Gauss arranged for the installation of two meridian circles (produced by Johann Georg Repsold and Georg Friedrich von Reichenbach in 1818 and 1819.Gauss was succeeded by Wilhelm Weber and Peter Gustav Lejeune Dirichlet, who served as provisional directors (though neither was an astronomer), and Dirichlet was replaced, upon his death, by Gauss's former assistant, Ernst Friedrich Wilhelm Klinkerfues.