Ferry was elected to be a deputy on the National Convention in 1873 and Hachette returned to the École Royale du Génie of Mézières to take over his position teaching mathematics.
Ferry ay elected upang maging isang kinatawan sa National kapulungan sa 1873 at Hachette ibabalik sa École Royale du Genie ng Mézières na tumagal ng higit sa kanyang posisyon ng pagtuturo sa matematika.