 In 1666, he received a part of the salary of the director-general of the Central Board of National Antiquities, and he was appointed to be its seventh assessor in 1667.In 1669, he was promoted to be the secretary of the National Archives.In the same year, he and Elias Brenner joined de la Gardie on an excursion through de la Gardie's fiefs, and Johan Hadorph made drawings of all the ancient monuments the party encountered.