Kate Walker here, keeping the light on Robbins Reef.
Robbins Reef marks a hazardous reef in New York Bay so does not need to be seen at a great distance. According to the 1892 Light List, my light is 58 feet above sea level. Coastal lights need to be seen from great distances so the light’s focal plane must be at a higher elevation.
Several light stations on the northeastern coast were located to take advantage of naturally high elevations, such as Block Island Southeast Lighthouse, Rhode Island, and Monhegan Island Lighthouse, Maine. On the west coast some lighthouses tended to be short towers built on sea cliffs high enough to project the light many miles at sea.
Ironically, the low clouds so characteristic of the west coast caused some station sites at high elevations to be moved to lower altitudes with taller towers in order to get the light below the low cloud levels, but high enough to be visible to ships at sea. The first Point Loma Lighthouse (1855), California, tower was only 40 feet tall but was located on a bluff providing a focal plane of 462 feet above the water. It was replaced in 1891 by a 70-foot-high tower built at the base of the bluff with a focal plane of 88 feet above the water.
Lighthouses were built on land, in the water, on islands, on top of ledges and cliffs, on breakwaters and piers, on caissons, and at least five are on fort walls. Some light towers are standalone structures, while others are attached or integral to the keeper’s quarters or fog signal building. Lighthouses were built from a variety of materials including wood, stone, brick, reinforced concrete, iron, steel, and even aluminum and fiberglass.
In addition to a light tower, a completely equipped light station on the mainland might consist of a keepers’ quarters, oil house, fog-signal building, workshop, water supply (generally a cistern), privy, landing wharf, boathouse and ways, barn, roads, walks, and fences. Some regions required special structures to provide access to the light tower. The elevated walkway or catwalk found on some of the piers of the Great Lakes was necessary for the keeper to get to the pierhead light during severe storms when waves washed over the pier or ice made it too dangerous to walk on the pier. Stations that retain most of their supporting structures exhibit a high level of historic integrity.
I’m gleaning all these wonderful descriptions of lighthouse architecture from The Historic Lighthouse Preservation Handbook.
Submitted January 21, 2018
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