Flavius Josephus, Antiquities of the Jews
William Whiston, A.M., Ed.

[134] There was also an ark made, sacred to God, of wood that was naturally strong, and could not be corrupted. This was called Eron in our own language. Its construction was thus: its length was five spans, but its breadth and height was each of them three spans. It was covered all over with gold, both within and without, so that the wooden part was not seen. It had also a cover united to it, by golden hinges, after a wonderful manner; which cover was every way evenly fitted to it, and had no eminences to hinder its exact conjunction. There were also two golden rings belonging to each of the longer boards, and passing through the entire wood, and through them gilt bars passed along each board, that it might thereby be moved and carried about, as occasion should require; for it was not drawn in a cart by beasts of burden, but borne on the shoulders of the priests. Upon this its cover were two images, which the Hebrews call Cherubims; they are flying creatures, but their form is not like to that of any of the creatures which men have seen, though Moses said he had seen such beings near the throne of God. In this ark he put the two tables whereon the ten commandments were written, five upon each table, and two and a half upon each side of them; and this ark he placed in the most holy place.