ON November 8, the centenary occurs of the birth of Johann Carl Friedrich Zollner, who in the course of a comparatively short career raised himself to a distinguished position among German astronomers as a pioneer in astrophysics. He was born at Berlin, and passed through the Universities of Leipzig and Berlin with distinction; after holding office as an extraordinary professor, he was appointed in 1872 to the chair of physical astronomy at Leipzig. That same year he was elected an associate of the Royal Astronomical Society. In 1865 he had turned his attention to the larger planets, and he afterwards advanced a theory of their constitution which met with wide acceptance, directed attention to the rapid changes in the cloud-belts of Jupiter and Saturn, and made observations of the rotation of the planet. On February 6, 1869, before Janssen and Lockyer devised their method of observing solar prominences in broad daylight, Zollner read a paper before the Saxon Society of Sciences on a method of doing this, but did not obtain a suitable instrument until some months later. In some of his work, Zollner was assisted by his pupil Hermann Carl Vogel (1842-1907), afterwards director of the astrophysical ob servatory at Potsdam. Zollner died on April 25, 1882, at the age of forty-seven years.