1. Triangulation between the Hudson River and Cape Henry and Ohio River : June 30, 1883 Yale Public content 1883. 2013-10-10T15:08:31Z. 2018-12-18T20:00:14Z. U.S. Coast and Geodetic Survey, issuing body. U.S. Coast and Geodetic Survey. English. cartographic image. Public. Middle Atlantic States.