With my curiosity awakened I've been hunting around, and found this fascinating page about the impact of the instrument in its day, and especially about an 19th century virtuoso on this instrument, "dark-complexioned" Boston musician Ned Kendall, who pioneered circus band music, and played for Queen Victoria, who was said to have presented him with a silver bugle

The site I linked to also has a few tunes with his name - Ned Kendall's Hornpipe and Ned Kendall's Favourite and Ned Kendall's.

Here's a taster:

An instrument known as the Kent Horn (dedicated to the Duke of Kent) was one of the first of these innovations, and looked like a cross between a saxophone and a bugle, but the keyed bugle was one of the best of the early innovations, recorded in use in America at the military academy at West Point as early as 1816. It caught on enormously in the succeeding decades but was eventually subsumed by another refinement when valves, developed in the 1830's and 1840's, replaced keys.

The development might be likened to the impact of the electric guitar in the 20th century, for simple horns were transformed into loud, agile, sonorous instruments perfect for demanding soloing performances in the days before amplification. Kendall himself remained a key-bugle player all his life.

Coinciding with these developments was the rise in martial activity in both Europe and the United States as both a civic duty and recreation. Local units sprung up all around the United States, often with colorful names and uniforms, and paraded in public as much as for performance value as for military instruction. Often these units had bands attached to enhance both booted measure and élan, and thus skilled musicians were much in demand and well-regarded.

Ned Kendall was one of the best. His playing is said to have been stunning, and he had a gift for improvisation and spontaneous elaboration of themes he heard only once...