Very fine marine parallel rulers in brass. The parallel ruler is the oldest and most traditional way to measure and trace routes and bearings. The principle is simple: the ruler is placed on the road to be measured and then, like a pantograph, the other part of the ruler is placed on one of the declination roses on the map to determine the angle. They are, essentially, two straight-edges hinged so that they maintain the same angle. By alternating the moving edge, and securely holding down the no...

A chart depicting the astronomical division of the earth. With on both sides a descriptionary text. All within an elaborate and very decorative border. A very fine item.Claude Buy de Mornas (d. 1783), géographe du roi (1764). Atlas Méthodique et Elémentaire de Géographie et d' Histoire, 1761, Atlas Historique et Géographique, 1762. A chart depicting the astronomical division of the earth. With on both sides a descriptionary text. All within an elaborate and very decorative border. A very fi...