Ophicleide

The ophicleide is a keyed bugle, and thus a type of horn. This long pipe is bent back over itself to make the instrument shorter for easier handling. It has nine to twelve keyes to control the opening of the holes, which serve to alter the length of the pipe for different pitches. Its mouthpiece is similar to those of the modern trombone and euphonium. The instrument is flared, and has a large bell.

Source:
http://en.wikipedia.org/wiki

The ophicleide was invented in 1817 and patented in 1821 by Jean Hilaire Asté (French). It was conceived as a keyed serpent - ophis is Greek for serpent and kleis for keys, thus ophicleide.

Soundclip

http://www.serpentwebsite.com/sound.htm - scroll down