Théodule Devéria help Mariette read inscriptions in Cairo and its surroundings. He tried to accurately document the archaeological sites using drawings, stampings and photographs. His calotype pictures from this trip are often poor in quality, showing a lack of technical skills. In 1860 he was appointed preserving assistant at the Louvre's Department of Egyptology. He revisited Egypt in 1861–62, traveling up the Nile to Philae at the First Cataract, and into Nubia to the Abu Simbel temples. After returning he helped Mariette prepare descriptions of the excavation in Egypt in 1850–54 for publication. In November 1864 Devéria met the future oriental scholar
Abu Simbel temples goddesses Hathor, Isis, Maat, Mut of Asher, Satis and Taweret; in one scene Ramesses is presenting flowers or burning incense. The capitals of the pillars bear the face of the goddess Hathor; this type of column is known as Hathoric. The bas-reliefs in the pillared hall illustrate the deification of the king, the destruction of his enemies in the north and south (in this scenes the king is accompanied by his wife), and the queen making offerings to the goddess Hathor and Mut. The hypostyle hall is followed by a vestibule, access to which is given by three large doors.