Post horn

The cornet was developed from the cone-shaped coach horn through the addition of valves, while the cylinder-shaped trumpets remained predominantly valveless for several decades.

[3] In the late 17th century, Johann Beer composed a Concerto à 4 in B♭, which paired a post horn with a corne de chasse as the two solo instruments, accompanied by violins and basso continuo.

One example of post horn use in modern classical music is the famous off-stage solo in Mahler's Third Symphony.

Notable musical examples include Capriccio on the departure of a beloved brother by Bach, which includes an "Aria di postiglione" and a "Fuga all'imitazione della cornetta di postiglione", both containing an octave jump similar to that of the postal horn.

Beethoven's Les adieux piano sonata is centered on a horn-like motif, again signifying the departure of a loved-one.

Schubert's Winterreise includes the song "Die Post", of which the piano part prominently features a horn signal motif.

Installed along winding, narrow mountain roads, the sign indicated that motorists should yield to incoming coaches, and let them pass safely.