27 x 40" Oceanic Navigation Chart from updated sources starting in the 1830 Office of Hydrography for the British Admiralty and being used and updated by NOAA or USC &GS Or other American or Foreign Naval sources in duration. Fine detailed condition . Manuscript additions evident in pencil from last use of 1978. This sheet covers

the north bay of San Pablo and the entrance to Napa River, Mare Island Straights, along the first naval facility on the west coast.