1908—Ixelles, Belgium

Emile Ergo, Professor of Harmony, Counterpoint, and Instrumentation at the Institute of High Musical Studies, Ixelles, Belgium, authors the treatise, Dans les propylées de l’instrumentation. About the family of trombones and use of clefs he says, “After the traditional rule, each species of trombone uses the clef of the corresponding voice.” He also clearly describes an alto trombone in E-flat, with the label “Trombone-alto (mi flat),” followed by a staff with alto clef and a notated e-flat on the staff. He labels tenor clef “Trombone-ténor (si flat),” followed by a staff with tenor clef and a notated b-flat on the staff (Ergo 38).