Letter of the Secretary of the Navy, communicating in compliance with a resolution of the 19th of March last [1866] a report of Rear Admiral Charles H. Davis, Superintendent of the Naval Observatory, in relation to the various proposed lines for interoceanic canals and railroads between the waters of the Atlantic and Pacific Oceans Letter of the Secretary of the Navy, communicating in compliance with a resolution of the 19th of March last [1866] a report of Rear Admiral Charles H. Davis, Superintendent of the Naval Observatory, in relation to the various proposed lines for interoceanic canals and railroads between the waters of the Atlantic and Pacific Oceans