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 the United States), all of them clearly indicating a “small” alto trombone in E-flat. The sources leave very little ambiguity in this respect, providing clear diagrams of the alto trombone range and key or alto trombone position charts. This is significant because it adds to the body of evidence suggesting the alto trombone is historically a D or E-flat instrument (on this subject, see also Extant Altos).