(b. Berg-Giesshubel, Saxony, 1710 ; d. Vienna, 1804), studied a t Dresden, chiefly under Zelenka, becoming violoncellist in the court chapel a t Zerbst, where he still was in 1761. as Konzertmeister, and as famous teacher. He composod church music, cantatas, etc. (Q.-L. ; Riemann). R0LLIG, K arl L eopold, from 1764-73 conductor of Ackermann's theatrical company a t Hamburg, was an improver of and virtuoso on the glass-harmonica, and inventor of the orphica and Xiinorphica (improved PF. and archi-PF). In 1797 he was appointed a t the Imperial Library, Vienna. He composed concertos and pieces for the above instruments; also interlude for orchestra, songs and theoretical works, etc. (Q.-L. ; Riemann).