I continue to add to the Alto in Treatises page. As indicated by the subtitle of the page (treatises, dictionaries, and methods), my criteria are quite broad for this post. I recently added a trio of early trombone method books: Braun (c. 1795), Fröhlich (c. 1811), and Nemetz (1827). I also added info from Praetorius’s Syntagma Musicum II (1619), as well as images from Praetorius (1619), Eisel (1738), and Albrechtsberger (1790). With the numerous other written sources, these help shed light on the role of the alto in trombone history. The document, which spans from 1600 to 1925, now includes well over 50 sources, the majority of them primary sources. Many of these will eventually be added to the general Trombone Timeline.