Who was the French professor that the Robert brothers built the world's first hydrogen balloon for?
Jacques Charles Jacques Alexandre César Charles (November 12, 1746 – April 7, 1823) was a French inventor, scientist, mathematician, and balloonist.
Joseph Galien Joseph Galien OP (born 1699, Saint-Paulien, France) was a Dominican professor of philosophy and theology at the University of Avignon, meteorologist, physicist, and writer on aeronautics.