Things of Middle-earth
Description:The Valaróma is the name of [Oromë's] great horn, the sound of which is like the upgoing of the Sun in scarlet, or the sheer lightning cleaving the clouds. Above all the horns of his host it was heard in the woods that Yavanna brought forth in Valinor; for there Oromë would train his folk and his beasts for the pursuit of the evil creatures of Melkor.
The Silmarillion, Valaquenta: Of the Valar
And Oromë tamer of beasts would ride too at whiles in the darkness of the unlit forests.... Then the sleeping earth trembled at the beat of [Nahar's] golden hooves, and in the twilight of the world Oromë would sound the Valaróma his great horn upon the plains of Arda; whereat the mountains echoed, and the shadows of evil fled away, and Melkor himself quailed in Utumno, foreboding the wrath to come.
The Silmarillion, Quenta Silmarillion, Ch 1, Of The Beginning of Days
Contributors: Dim Genesis, 06.07.03
added quotes: Elena Tiriel 29Nov05