Left image: Alexander Dallas Bache, second superintendent of the U.S. Coast Survey.Right image: Alexander Dallas Bache peering through a sextant, a navigation instrument that measures the angular distance between two visible objects.
Alexander Dallas Bache was the second superintendent of the Coast Survey. Under Bache, the Coast Survey expanded its core missions of hydrography, geodesy, topography, and the printing arts. He directed tide observers to make meteorological observations, began geomagnetic studies, and guided the development of mathematical techniques for:
Under his leadership, the Coast Survey was not only a chartmaker, but also one of the great science organizations of the world.