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First-order rotating catadioptric Fresnel lens, dated 1870, displayed at the Musée national de la Marine, Paris.In this case the dioptric prisms (inside the bronze rings) and catadioptric prisms (outside) are arranged to concentrate the light from the central lamp into four revolving beams, seen by sailors as four flashes per revolution.
It received the station's original fourth-order Fresnel lens that it continues to display. The beacon's height of 51 feet (16 m) made it the tallest light on Puget Sound. The tower on the original lighthouse was removed and the building continued in use as residence for the keepers. The station was automated in 1976. [7]
The tower was originally equipped with a fourth-order lens manufactured by Chance Brothers that produced a fixed red light. [6] This lens was replaced at some point with a Fourth Order Fresnel lens manufactured by Sautter & Cie. [10] A catwalk extends from the second story of the lighthouse along the pier to the shoreline. [9]
By specification, the 4th Order Fresnel lens would generate alternate red and white flashes of light every 30 seconds that would be visible 17 nautical miles (31 km) out to sea. In 1969, the Fresnel lens was retired (it is currently on display at the Point SLO Lighthouse) and replaced by an automated electric light.
All of this rest on a block of concrete within the breakwater. Originally the tower was equipped with a four-panel fourth order Fresnel lens that flashed every 10 seconds at a 72-foot (22 m) focal point. The lens revolved on ball bearings and was driven by a clockwork mechanism driven by weights within a hollow central iron column.
Point No Point Light ; Location: Hansville, Washington: Coordinates: 1]: Tower; Constructed: 1879: Foundation: Masonry: Construction: Brick and stucco: Automated: 1977: Height: 30 feet (9.1 m): Shape: Square: Heritage: National Register of Historic Places listed place : Light; First lit: 1880: Focal height: 27 feet (8.2 m): Lens: Fifth order Fresnel lens (1880); Fourth order Fresnel lens (1898 ...