Isaiah 21:7

And he saw a chariot with a couple of horsemen, a whole army of mounted soldiers riding two abreast, a chariot of asses, and a chariot of camels, the various mounts thus being described, as the enemy rode forward to the attack, their pack-animals remaining behind with the baggage. And he hearkened diligently with much heed, with the closest application, his object being to get more information concerning the Persian invaders.