Letter, from Heinrich Christian Schumacher to Sir John Herschel, dated at Altona Autograph letter signed by sender. [Otto] Rosenberger has calculated perturbations of Halley's Comet by the inner planets. [Wilhelm] Beer and [J. H.] Mädler have a map of the moon and have located two moving spots on Jupiter. F. W. Bessel's assistant has 5 March 1835