Screwpiles: The Forgotten Lighthouses

Funck-Heap Lamp In 1892, smaller lighthouses adopted a new lamp. Called the Funck-Heap lamp, it was a standard Argand lamp with a single, one and one eighth-inch-diameter wick. A flame-spreading button in the center of the flame got red-hot and helped to keep the flame a constant size and shape. A screw thread on the tube carrying the wick fed the wick to the flame. The Funck-Heap lamp became the standard lamp used in all fourth-order (and smaller)

A concerted effort to relight all three lighthouses stumbled on the difficulty in procuring the sixth-order lenses, and there was

correspondence about using large steamship lenses as substitutes. On July 11, 1862, White Shoal, Point of Shoals, and Deep Water Shoals Lighthouses were again operating using steamship lenses. Lights Out on the James River, August 1862–May 1864 Due to continuing rebel harassment of the lighthouses and because the war effort had shifted away from the James River, the apparatus in all three lighthouses were taken down and the lights again went dark from August 1862 until 1864. In May 1864, all three lighthouses were back in service using sixth-order lenses, but there were complaints about the quality of light. In a letter from November 16 to Rear Admiral Schubrick, Fifth District Engineer M. Newman wrote, “The lens at Point of Shoals Light House (6 th order) illuminates about 1/3 rd of the horizon and as the bend of the river at that point is very sharp, it follows that to vessels approaching the lighthouse up or down, the light is not visible till close upon it and on dark nights when the coast is not visible, they frequently get ashore. I would respectfully request that a lens be furnished that would illuminate ¾ of the horizon.” 4 That request for a change in lenses, however, was never fulfilled, and subsequent reports show all James River screwpile lighthouses continuing to employ sixth-order lenses. Lamps and Lamp Fuel The U.S. Lighthouse Service used the Argand lamp extensively. The lamp used a tubular wick along with a glass chimney specifically designed to maximize the flow of air over the burning wick. The result was a cleaner burning, much brighter lamp. A chart showing the various lamps used in the service from the late 1700s to the early 1900s is shown in the appendix. There were many variations and improvements to the original Argand design. The improvements all aimed for a brighter light with less maintenance while reducing the consumption of oil. One series of improvements involved adding concentric wicks to increase the candlepower of the lamp. The larger, triple and quadruple lamps were used with the large first-order through third-order lenses. The other series of improvements centered on metering the flow of oil to the wick. The simplest original design relied on capillary action of the oil moving up the wick from a lower oil reservoir. Later designs added pressure to increase the lamp efficiency.

Funk-Heap Lamp. Images by Thomas Tag

lenses in the U.S. Lighthouse Service. All the lighthouses using a fourth-order lens refitted to use the lamps as quickly as they could be manufactured. Later fifth-order and sixth-order lamps were fitted with the same lamp design, with slight variations in the flame spreader and chimney. In March 1892, after receiving complaints about poor visibility, Inspector Train of the Fifth District requested Funck-Heap lamps be installed in all of the James River lighthouses shortly after that. Those lighthouses continued to use oil lamps as the illuminant until 1934, when the James River lighthouses and Nansemond River Light changed to incandescent oil vapor lamps. 5 Lamp Fuel The Deep Water Shoals, Point of Shoals, White Shoal, and Jordan Point Lighthouses all used whale oil, specifically sperm oil, when they were first established. Sperm oil was expensive. The cost was $2.15 per gallon in 1856, equivalent to $58.17 per gallon in 2017. The Lighthouse Board was purchasing large amounts of sperm oil. An announcement for bid proposals in January 1856 required contractors to supply 105,450 gallons of sperm oil. 6 The increasing cost, the diminishing supply of sperm oil, and the increase in the number of lights (500 in 1864) in the United States forced the Lighthouse Board to look for alternatives. Colza (or rapeseed) oil was in use in France and England. The board imported 1,000 gallons of colza oil in May 1864, along with seeds for cultivation. There was some success with the oil, but the United States never

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