‎MOHR, GEORG.‎
‎Euclides Danicus - Amsterdam 1672.‎

‎Copenhagen, 1928. 4to. Original printed wrappers. VIII,(4),36,41 pp. and 3 plates in facsimile.‎

Reference : 28740

‎Facsimile reprint of the Danish edition of Mohr's Euclides Danicus, printed in Amsterdam 1672 (a Dutch edition was issued simultaneously). Also contains a German translation of the Danicus and a preface in German by Johannes Hjelmslev. Until 1928 Mascheroni was credited with being the first to prove that all the constructions in the first 6 books of Euclid's Elelements could be constructed with compass alone. Hjelmslev discovered that Mohr had proven this in his Danicus 125 years before Mascheroni.‎