"[After the Great Deluge had wiped out mankind] Rector Pelagi [Lord of the Sea Poseidon] laid by his three-pronged spear and calmed the waves, and, calling from the deep Triton, sea-hued, his shoulders barnacled with sea-shells, bade him blow his echoing conch to bid the rivers, waves and floods retire. He raised his horn, his hollow spiralled whorl, the horn that, sounded in mid ocean, fills the shores of dawn and sunset round the world; and when it touched the god’s wet-bearded lips and took his breath and sounded the retreat, all the wide waters of the land and sea heard it, and all, hearing its voice, obeyed.
Ovid, Metamorphoses 1.332
There is a story similar to this about the shell of Triton. He, too, when he had hollowed out the trumpet he had invented, took it with him against the Gigantes, and there blew strange sounds through the shell. The Gigantes, fearing that some wild beast had been brought by their adversaries, took to flight, and thus were overcome and came into their enemies’ power.
Pseudo-Hyginus, Astronomica 2.23