Screwpiles: The Forgotten Lighthouses

Thimble Shoal screwpile light and the caisson that replaced it

Both lighthouses were fitted with fog bells and continued to use sixth-order lenses and Funck lamps. A Stevens Bell mechanism, used to control the bell, consisted of a clockwork winding mechanism that used a heavy weight to power the bell hammer for about two hours. Using the mechanism, the bells rang in a consistent, distinct pattern (one ring every 10 seconds, for example). Navigational charts listed a lighthouse’s ring pattern, allowing a ship’s captain, navigating through fog, to pinpoint his location. Thimble Shoal, Nansemond River, and Middle Ground Lighthouses In 1872, a screwpile lighthouse was erected northeast of Willoughby Spit to mark Thimble Shoal. This replaced the light vessel anchored off Willoughby. Increasing river traffic prompted the addition of the Nansemond River Lighthouse, built in 1878, and Middle Ground Light, built in 1891. Steamboats and river traffic reached their peak around 1910, with a hundred steamboats operating on the James River

supporting screwpiles, including the center pile. Riprap surrounded the foundation. A fire destroyed the wooden lighthouse eight years later, marking the beginning of a series of disasters that plagued Thimble Shoal. A lighthouse from the Lazaretto Depot, originally planned for Bells Rock, was diverted to Thimble Shoal and fitted on the old, still-stable foundation.

between 1813 and the 1930s. Thimble Shoal Light

In 1872, a screwpile lighthouse, built at the Lazaretto Depot, with a fourth-order light and two fog bells, replaced the lightships that, historically, had guarded the two-parallel sandbars entrance to Hampton Roads. It had a hexagonal foundation with seven

A continuing series of incidents led to the 1912 installation of a new caisson-type lighthouse next to the foundation of the old screwpile foundation.

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