Escher was hired by the
Japanese government as a
foreign advisor from September 1873 to July 1878, along with fellow Dutch civil engineers
Johannis de Rijke and
Cornelis Johannes van Doorn. Escher accompanied de Rijke on an exploratory visit to Shanghai and compiled a report that garnered considerable attention, though it did not culminate in immediate implementation. After returning to the Netherlands, he worked in
Maastricht. During this time, he recorded in his diary his difficulty as a Protestant in finding a suitable marriage partner in
Roman Catholic Maastricht who would also be able to satisfy his equation v = 1/2m + 10, where
v was the age of the woman, and
m the age of the husband. In 1882, Escher married Charlotte Marie Hartitzsch, with whom he had two sons. She died in 1885, and in 1892 Escher married Sara Gleichman, with whom he had three more sons. Escher worked as a hydraulic engineer in
Leeuwarden. In 1903 the family moved to
Arnhem. ==Notes==