Howcome Firemen in the 1800s always carried a horn or bugle?

Question

You see photos, lithographs, portraits, and paintings of firemen in the 19th century carrying a bugle or a horn, so what were they used for, and how were they used?

Answer 1

The siren wasn't invented yet...

Answer 2

to warn pedestrians and other traffic to move or get run over.

Answer 3

i would say just by logic that it would be the siren that we now have electronically on vehicles.  They probably didn't have the technology for that in the 1800s.