1901—Chicago, Illinois

Lyon & Healy, a prominent American manufacturer and distributor of musical instruments, includes numerous alto trombones, all specifically labeled as E-flat instruments, in their New and Enlarged Catalogue of Band Instruments. Shown below are 4 of the altos listed in the catalogue: a slide alto and three valve altos (public domain) (Lyon & Healy 1901, pp. 45, 15, 28, 40).