Rare separately published example of this fine chart of Mobile Bay, first published by the United States Coast Survey in 1856.
The present example includes several notes, which provide clues to its dating. A note below the title from the C. Patterson, Superintendent of the US Coast Survey provides an issue date of September 1877. The map also states that "Aids to Navigation are corrected to 1885."
The chart is printed on thick paper and was clearly a separate issue, and includes navigational pencil markings showing at least 4 approaches to the Light south of the Harbor, where the ships would have entered the main channel into the harbor. The chart also includes an elaborate set of sailing directions, soundings, coastal features, etc.
The United States Office of the Coast Survey began in 1807, when Thomas Jefferson founded the Survey of the Coast. However, the fledgling office was plagued by the War of 1812 and disagreements over whether it should be civilian or military controlled. The entity was re-founded in 1832 with Ferdinand Rudolph Hassler as its superintendent. Although a civilian agency, many military officers served the office; army officers tended to perform the topographic surveys, while naval officers conducted the hydrographic work.
The Survey’s history was greatly affected by larger events in American history. During the Civil War, while the agency was led by Alexander Dallas Bache (Benjamin Franklin’s grandson), the Survey provided the Union army with charts. Survey personnel accompanied blockading squadrons in the field, making new charts in the process.
After the Civil War, as the country was settled, the Coast Survey sent parties to make new maps, employing scientists and naturalists like John Muir and Louis Agassiz in the process. By 1926, the Survey expanded their purview further to include aeronautical charts. During the Great Depression, the Coast Survey employed over 10,000 people and in the Second World War the office oversaw the production of 100 million maps for the Allies. Since 1970, the Coastal and Geodetic Survey has formed part of the National Oceanic and Atmospheric Administration (NOAA) and it is still producing navigational products and services today.