1. Triangulation between the Atlantic coast and West Virginia. June 30, 1892 Yale Public content 1892. 2013-10-29T17:32:13Z. 2013-11-21T21:38:55Z. U.S. Coast and Geodetic Survey, issuing body. U.S. Coast and Geodetic Survey. English. Public. East (U.S.) and Middle Atlantic States.