 On 12 April 1818, Stölzel and Blühmel registered a joint patent for ten years.The same year, on 16 October 1818, the first work for valved horn was performed - the "Concertino für drei Waldhörner und ein chromatisches Ventilhorn", written by composer and horn player Georg Abraham Schneider.Stölzel's early two-valve horn design was soon expanded to three by instrument builder C. F. Sattler of Leipzig, and the first valve trumpets were built in 1820.