Added 8 more primary sources to the Alto Trombone Timeline, bringing the total number of primary sources for that timeline to more than 2 dozen. The sources (Gevaert, Riemann, Jadassohn, Saro, Galli, Mayerhoff, Coon, and Corder) are 19th and early 20th century orchestration texts from a wide range of locations (Germany, Italy, Belgium, England, and [...]