from a trigonometrical survey under the direction of A.D. Bache, Superintendent of the Survey of the Coast of the United States ; triangulation by E. Blunt, Assist. ; topography by A.M. Harrison, Assistant ; hydrography by the party under the direction of W.P. Trowbridge, Assist. ; redd. drng. by F. Fairfax and L. Karcher ; engdd. by E.H. Sipe, F.W. Benner, and W.A. Thompson