2013-09-26 / Front Page
Pointe aux Barques Fresnel lens is home
Pointe aux Barques Lighthouse Society President Bill Bonner tells about the lens and its journeys.
On Sept. 7, 1873, the lighthouse supply ship “Haze” delivered a 16-panel, thirdorder, Fresnel lens to the Pointe aux Barques Lighthouse, where it was assembled at the top of the 89-foot tower and immediately went into service.
The lens is about three and a half feet in diameter, 5 and a half feet high and weighs approximately 1,400 pounds. It is a third order Fresnel lens, with first order being the largest and sixth the smallest.
The lens gets its powerful effect by using panels of glass and the principle of refraction. This design was developed and introduced by French physicist Augusta Fresnel in the early 1800s. The lower panels are called lower catadioptric and the top panels are called upper catadioptric. The round circle in the center of the lower panels is the catadioptric. All the prisms are precisely installed and balanced to focus the light source into the round catadioptic in the center of the lower panel.
This lens, delivered to the Pointe aux Barques Lighthouse, was the only 16- panel, third-order lens ever installed on the Great Lakes, possibly in the United States, making the rare optic especially valuable.
When in operation, the lens continually warned mariners of the dangerous rock ledge which stretches two miles into Lake Huron around Pointe aux Barques.
It saw duty during the fire of 1881, through the Storm of 1913, World War I, the Armistice Day Storm of 1937, World War II, and the Korean War before it was removed from the tower in 1969 and stored in a Coast Guard warehouse in Detroit.
In 1970, the lens was moved to Harbor Beach and displayed in the municipal office, but later moved to the Grice Museum. In 1987, the lens was moved to Huron City Museum, where it remained until 2013.
On June 1, after a five-year effort by the Pointe aux Barques Lighthouse Society, the Coast Guard and the Department of Justice, the lens was moved to the U.S. Coast Guard Station at Harbor Beach.
Part of the effort included many months of research into where the lens was and why it had been moved; and, the society needed to provide the Coast Guard with written language that conclusively proved the lens was the property of the U.S. Government.
In August, lampist Kurt Fosburg began cleaning and restoring the irreplaceable artifact. Harbor Beach resident Scott Richardson and Pointe aux Barques board member Larry Becker assisted Fosburg with the moving and reassembly of the lens.
Bonner notes that without the cooperation of the U.S. Coast Guard in Harbor Beach and the support of the Huron County Road Commission the society would not have been able to complete the venture. He adds that the State Historic Preservation Office provided the majority of the funds for the restoration through a grant made possible by the State of Michigan Lighthouse License plate program. The Pointe aux Barques Lighthouse Society provided the remaining monies necessary to complete the work. The lens has been mounted on a specially-built, rotating stand. The museum will be open seven days a week from 10 a.m. till 5 p.m., until Sunday, Oct. 13. Bonner notes that weekends are best to view the lens, because it is set into motion. The Pointe aux Barques Lighthouse Museum is located in the Thumb of Michigan just off M-25, six miles North of Port Hope.
About the Pointe aux Barques Lighthouse:
From 1848 to 1949, the Pointe aux Barques lighthouse was manned by lighthouse keepers. The first was Peter L. Shook and the last was Daniel McDonald. Its construction began in 1838 on a site described as “the most easterly of the two points, known as Point-aux-Barques, near the entrance to Saginaw Bay (sic) …” It was completed in 1847. Shook arrived at the station, March 6, 1848. He passed away the following May. His wife, Catherine, took over and served as lighthouse keeper until 1851. An 89-foot Cream City Brick tower station was constructed in 1854 and outfitted with a third-order Fresnel lens. A clockwork motor rotated the lens around the lamp at an exact rotational speed which placed the lens between the mariner and the lamp every two minutes, creating a bright flash. The lens, with its focal plane at 93 feet above sea level, had a range visibility of 16 miles. For a time, it was replaced with a fixed light, but after that was deemed unacceptable, the flashing light was returned. It was upgraded to a 34,000-candlepower incandescent oil vapor lamp system, with a range of 18 miles. In 1932, an incandescent electric bulb was installed within the Fresnel, increasing the candlepower to 120,000. In the early 1950s, the lighthouse was completely automated. The Fresnel was removed and replaced with twin DCB-224 aero automated beacons. The two-story dwelling was attached by a covered walkway. A second dwelling was built in 1908. In 1875, the Port Hope Life Saving Station was expanded on the lighthouse reservation, complete with a building which featured exterior diagonal bracing and intricate bracketing supporting the overhanging eaves.
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