, "Engraver to the King", took him into his workshop, where he completed a seven-month training course; engraving portraits for art dealers and providing some illustrations for the publisher, . In 1740, with some assistance from Hyacinthe Rigaud, he became self-employed. In 1742, King Louis XV officially granted permission for Protestants to attend the Académie Royale. The following year, however, he accepted an offer to become a court engraver back in Berlin. He returned there in the middle of the Second Silesian War, and his first major assignment was creating tactical maps of the battles of Kesselsdorf and Soor, which were published in 1746. That same year, he married Dorothée Luise Viedebandt, whose father was Director of the Russian Trading Company in Berlin. A large dowry may have been a factor. Two years later, their son August was born. He turned out to be an unruly child, who sometimes sold his father's works secretly and squandered the money.