Georg Mohr

Georg Mohr (1640 to 1697) was a Danish mathematician born in Copenhagen who is remembered for a book that almost nobody read in his lifetime. In 1672 he published Euclides danicus, which shows that every construction in the first books of Euclid can be carried out with compasses alone, without a straightedge. Mascheroni gave the same result about 125 years later, and Mohr's priority was recognised only after a copy of the book turned up in a bookstore in 1928. Mohr studied in Holland, France and England, hoping to learn from Huygens, and he corresponded with Leibniz and with Tschirnhaus. He fought and was taken prisoner in the Dutch-French wars, declined a post as supervisor of royal shipbuilding in Denmark, and spent his last years working with Tschirnhaus at Kieslingswalde near Gorlitz.