Baltimore Light Station
Chesapeake Bay, Gibson Island vic., Anne Arundel County
The Baltimore Light Station consists of a wooden caisson, which supports a round 30-foot-diameter cement-filled cast-iron cylinder painted red, upon which rests a brick 2 1/2-story 38-foot-tall, octagonal-shaped brick quarters painted white, with a mansard roof surmounted by a one-story black iron lantern. As is the case with caisson-type lighthouses, it is an integral station, i.e., the keeper's quarters, fuel storage areas, and lantern room are part of the same structure. The first two stories are masonry, and the upper 1/2-story is a wooden mansard roofed watch room. The combination dwelling and lantern have elements of the Second Empire architectural style. At the top of the first level is a single corbeled brick belt, followed by two normal belts, and then two additional corbeled belts. At the top of the second level and just below the mansard roof are three corbeled belts. Fenestration consists of an entrance door on the east and west side with a single window above on the second level. The door on the west side is made of 3-inch sheet iron. The doorway on the east side has been filled with concrete block. There are pairs of windows on the first and second levels of the north and south sides. All the windowsills and window and door lintels are made of cut granite. The original 6/6 sash windows have been removed and replaced with louvered acrylic sheets. There is a gable-roofed dormer window on the north, south, east and west sides. The dormers were removed, probably in 1988, and rebuilt in 1992. The lens is a 250mm acrylic lens, serial number 90521, with a red sector. It is powered by a single solar panel mounted on the upper gallery rail on the south side. The pedestal for the original fourth-order lens is still being used. Baltimore Lighthouse was outfitted with a fog bell signal when first built, but it was replaced with a foghorn sometime before 1923. In preparation for automation, the illuminant was changed from oil to acetylene and the clock-operated fog signal discontinued and was replaced by a fog bell Buoy 6C on May 1, 1923. The Baltimore Lighthouse is located in 24 to 29 feet of water on the western edge of the main ship channel at the mouth of the Magothy River marking the south entrance to Craighill Channel, northern Chesapeake Bay, near Gibson Island. Owned and managed by the U.S. Coast Guard in District 5, access to the lighthouse is via boat.
Baltimore Lighthouse was the last lighthouse built in the Chesapeake Bay, completed in 1908, 28 years after it was first requested. It was the largest wooden caisson built in the United States, perhaps in the world, when built, and it was the deepest caisson to be sunk in the United States. Baltimore Light Station is significant for its association with federal governmental efforts to provide an integrated system of navigational aids and to provide for safe maritime transportation in the Chesapeake Bay, a major transportation corridor for commercial traffic from the early 19th through 20th centuries. Of the eleven pneumatic caisson lighthouses built in the United States, seven were built in the Chesapeake Bay; three were built in the Virginia portion of Chesapeake Bay (Wolf Trap Lighthouse, 1894, Smith Point Lighthouse, 1897, and Thimble Shoal Lighthouse, 1914) and four in the Maryland portion of Chesapeake Bay (Solomons Lump Lighthouse, 1895, Hooper Island Lighthouse, 1902, Point No Point Lighthouse, 1905, and Baltimore Lighthouse, 1908). Baltimore Light Station was the first and only nuclear powered lighthouse in the United States, being the site of a Coast Guard experiment in May of 1964. A 4,600-pound SNAP-7B Strontium-90 powered 60-watt isotopic fuel cell generator was installed by crane from a Coast Guard buoy tender and passed through the east doorway on a trolley platform. The atomic powered generator, smaller than a 55-gallon drum, was housed in a specially constructed heavy steel box. The test ran for a year and upon completion the nuclear equipment was removed and nuclear power has not been attempted since. A Geiger counter test detected no nuclear contamination.