Screwpiles: The Forgotten Lighthouses

Specifications The specifications for the three James River screwpiles were very detailed. All three screwpiles were to be of similar construction. The foundation was to consist of five iron piles, five inches in diameter and fitted with a two-foot-diameter iron screw. Four

pilings would form a square, 20 feet to a side with one pile in the center. The piles were to be driven 10 feet into the river bottom with the top standing three feet above mean high water. The foundation specifications continued in detail, including the size and length of bolts, supports, tension rods, wood pilings, and joists. 13 House Details The house structure included three-inch by nine-inch yellow pine joists, set on 20-inch centers. The house itself, framed in yellow pine, 17 feet 6 inches square and 9 feet high, included four rooms: a kitchen, a sitting room, a storage room, and a bedroom. The kitchen, situated next to the coal bin, was equipped with a single potbelly stove. A hoisting apparatus enabled one man to lift the lighthouse boat to the gallery level. A lightning rod protected the structure. The exterior and interior walls were one-inch tongue and-groove white pine. The plans, however, failed to specify insulation. The roof was heavy tin over white pine boards. Pipes led from the gutters to two internal water tanks. A cast-iron roof plate supported the cast iron cupola. Access to the cupola was by an interior stepladder. The glass specified for the cupola windows was French plate glass a quarter inch thick. The plans also specified a color scheme, with the structure painted white inside and out. Red lead paint protected the iron foundation, while the gallery floor, the roof, and the lantern room exterior were olive brown. 14

All plans National Archives RG 26

Although the specifications designated the use of sixth-order Fresnel lenses, pressed glass masthead lenses were originally installed. Trials testing both masthead and Fresnel lenses had shown that the pressed-glass lens adequately served the needs of river navigation. The sixth-order Fresnel lenses were finally installed when the lighthouses were relit after the Civil War.

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