Background: The bugle and the flugelhorn were originally valveless instruments in which the tubing is conically tapered from the mouthpiece to the bell flare. The bugle was used primarily for military signalling while the  flugelhorn was used for the hunt.  In 1810, in Dublin, Ireland, the bugle-maker and inventor Joseph Halliday installed holes with saxophone-like keys along the length of a bugle, and produced the first keyed bugles which could play an entire chromatic scale. My Keyed Bugles are found in the Flugel Horn Gallery.
 
In 1818 inventors Blühmel and Stoezel patented a form of piston valves which thereafter called "Stoezel valves". In 1828, an inventor named Halary (otherwise known as Jean-Hilaire Asté) added 2 Stoezel valves to a circular posthorn, calling it a ?cornet ordinaire.? A few years later he created a  bell-forward instrument which he called the ?cornet-a-pistons,? or ?cornopean.? In the 1840's, Adolph Sax also produced valved bugles or "Saxhorns" ranging from a Eb Soprano to a Eb Bass.

The modern cornet as we know it today, with the valve casings in the middle between the lead pipe and bell tubing, and with a characteristic "shepherd?s crook" bend at the beginning of the bell tubing, was first manufactured by Antoine Courtois in 1855, and was called the modèle anglais.  It should be noted that the "Shepard's Crook" was merely a way to practically shorten the horn and that there are several cornets made with straight crooks.  It is said that the warmer more mellow tone of the cornet is due to the fact it is a conical-bore instrument and the trumpet is a cylindrical bore instrument. In fact both are conical-bore instruments with the trumpet being only slightly less conical than the cornet.  Listen to the Cornet Range  or a Cornet Solo.