Screwpiles: The Forgotten Lighthouses

James River lighthouses. Pressed-glass lenses, also known as steamship lenses or seventh-order lenses, were made by pouring molten glass into molds. Although the design was based on the Fresnel technology, the steamship lenses were not as efficient as the higher-order Fresnel lenses. Steamship/Fresnel The steamship lenses served the James River lighthouses until they were spirited away or destroyed by Confederate raiding parties. G. Caster Smith, assistant engineer, surveying the damaged lighthouses, confirmed in his July 21, 1862, letter that steamship lenses were in use. “Deep Water Shoals, From the appearance of the lantern, a steamship lens has been used. No appearance of having had a pedestal.” 3 A steamship lens would have been suspended in the lantern room, while a sixth-order Fresnel lens would have been mounted on a pedestal. His report later stated the same was true for White Shoal and Point of Shoals.

Haines Lamp

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