As he was growing up he always knew that his father's major project was the map of France and in the 1770s he began to become more and more involved in assisting his father with the project.
Bilang siya ay lumalaki up siya lagi, alam na ang kanyang ama malaking proyekto ay ang mapa ng France at sa 1770s siya ay nagsimulang maging mas at mas kasangkot sa tumutulong sa kanyang ama sa mga proyekto.