What is this Antique Brass Instrument on display at the Musical

Does anyone know what type of instrument this is? It looks like some type of Euphonium, but obviously very different.

Nothing else sounds like vintage brass: These CSO musicians are

Slide Trumpet in E-flat – Duke University Musical Instrument

Vintage Wood and Brass Phonograph Music Box Plays Swan Lake

Harris Slide Trumpet — Robb Stewart Brass Instruments

Late 19th Century Antique Brass Cornet - Musical Instrument in

For Sale - Antique Musical Instrument Metalware from Chai Art and Antiques - Antique Brass Handmade Musical Instrument - Natural HornHas a small split

Antique Brass Musical Instrument Natural Horn, Span 37 cm

What is this Antique Brass Instrument on display at the Musical Instrument Museum in Brussels, Belgium? - Music: Practice & Theory Stack Exchange

Made In London ( United Kingdom / England ). 70- 80 Years Old Antique. In Good Original Condition. ( As Per Age ). Has Boosey & Co. Trade Mark With

Vintage Old Antique Brass Hand Playing Trumpet / Tuba Musical Instrument LONDON

Henry G. Lehnert, Baritone shoulder horn in B-flat

Old ANTIQUE BRASS TRUMPET Bugle Horn as Found Musical Instrument

Its a Musical trumpet and its iproduce loud sound.

Trumpet Brass Musical Instrument - Small Trumpet,Musical Trumpet,Musical Gift

What is this horn-like brass instrument which encircles the player's body? - Music: Practice & Theory Stack Exchange

Preserving History — Robb Stewart Brass Instruments

Music to my ears ??? Spotted this old tuba for sale at Arthur