German astronomer and physicist, born at Berlin on the 8th of November 1834. From 1872 he held the chair of astrophysics at Leipzig University. He wrote numerous papers on photometry and spectrum analysis in Poggendorff’s Annalen and Berichte der k. sächsischen Gesellschaft der Wissenschaften, two works on celestial photometry (Grundzüge einer allgemeinen Photometrie des Himmels, Berlin, 1861, 4to, and Photometrische Untersuchungen, Leipzig, 1865, 8vo), and a curious book, Ueber die Natur der Cometen (Leipzig, 1872; 3rd ed., 1883). He died at Leipzig on the 25th of April 1882.
