The flugelhorn is a brass instrument that resembles a trumpet but has a wider, conical bore. Some sources falsely consider it to be a member of the saxhorn family developed by Adolphe Sax (who also developed the saxophone). Other historians assert that it derives from the valve bugle designed by Michael Saurle. The German word Flugel translates into English as wing or flank. The instrument was used on the battlefield to summon the flanks of an army.