Devils Island Lighthouse
A homecoming occurred on Devils
Island in 1992 when a marine jewel was returned to its protective watch
tower overlooking the waters of western Lake Superior. The gem, a repaired
lighthouse lens, was hoisted back up to the lantern atop the Devils Island
Lighthouse for viewing by future visitors.
The story of this lens' evolution began long ago. After centuries of navigating
with the guidance of bonfires and unreliable lamps, mariners were still
straining to see the flickering flames of 19th century lighthouses
and pleading for brighter lights. Their pleas were answered in 1822 when
French engineer Augustin Fresnel devised the now-famous Fresnel (pronounced
fray-nell) lens.
Resembling a giant glass and brass beehive, the Fresnel lens consisted of a series of glass "bull's-eyes" - round magnifying lenses encircled by concentric rings of prisms. The ingenious lens collected the light rays produced by whale-oil lamps, bent (refracted) them, and sent the concentrated beam across the water to waiting seamen. By 1860 the Fresnel lens, built by skilled craftsmen in and around Paris, was in use world-wide.
Such a device was first lit on Devils Island, the northern-most of Lake Superior's Apostle Islands, on the night of September 30, 1891. The light marked a critical turning point in the shipping lanes of Lake Superior. In 1901, a larger 3rd order lens, 40 inches in diameter and about 6 feet in height, was placed in service in the Devils Island tower. The lens was manufactured by the Paris firm of Henry LePaute. It flashed a red light and was visible for 22 miles.
The Devils Island light flashed its red beam for nearly a century before surrendering to modernization in 1989. The venerable, but still functional, 3rd order lens was lowered from its tower and replaced by a small, modern solar-powered beacon. The beacon requires less energy and maintenance to perform its function of guiding the giant freighters and fast-increasing numbers of pleasure boats.
For three years the dismantled historic 3rd order Fresnel lens rested in protective crates in the Apostle Islands National Lakeshore's museum storage, awaiting repair. Two glass ring prisms had been shattered during the solarization move. A multitude of other chips and cracks in the lens bear witness to the wear and tear of 88 years of operation.
In July of 1992, physical stabilization and historic preservation of the lens began in Bayfield upon the arrival of Greg Byrne, an objects conservator with the National Park Service at Harpers Ferry, West Virginia. An expert in glass, ceramics and stone, Mr. Byrne labored seven days a week for three weeks to repair the lens.
About a week was required to reassemble the jigsaw puzzle of glass fragments from the two broken ring prisms. Optical transparent epoxy, which tolerates the -40F to +120F temperature range of a Lake Superior lighthouse, was used in the tedious and critical process of mending and molding the broken lens. Where pieces fit together, the epoxy functioned as an adhesive. Fissures between glass fragments were filled by injecting the epoxy. Mr. Byrne enclosed larger gaps in the prism with a mold which was filled with epoxy. The hardened epoxy was then painstakingly shaved with a knife until the rings regained their original shape. Mr. Byrne was careful to repair only modern damage and historic damage that might endanger the stability of the lens. Much historic damage remains, as part of the story told by sparkling, but imperfect prisms.
Another stabilization procedure was the replacement of brittle and loose glaze between glass rings, and between glass prisms and their brass frames. The old putty, which was probably white lead and linseed oil, was replaced with vinyl spackle. After brass and glass were cleaned with alcohol and acetone, the repairs and preservation were complete. The eight sections comprising the lens, each about the size and weight of a person, were returned to their wood crates for the journey back to Devils Island.
On August 31, 1992, an Army National Guard Chinook helicopter gingerly set down in the patch of blueberry bushes near the Devils Island Lighthouse tower. The helicopter's crew assisted National Park Service employees in carefully unloading the crates containing the lens and its heavy pedestal. A hoist system was rigged at the top of the tower to raise each piece of the lens, in sequence, to the lantern room, 80 feet above the ground.
For smooth raising of the heavy and delicate lens sections, a tractor was used to apply tension to the hoisting rope, while guy lines held by crew members kept the pieces from swinging on the ride up. Some of the metal sections of the lens pedestal weighed nearly 600 pounds. Maneuvering room was at a premium at the top of the hoist - workers on the tower catwalk, managing the boom and receiving the sections, had little margin for error! Retired airline mechanic and lens expert Bob Bolen directed the crew from the lantern room.
One by one, the pedestal pieces were reassembled, and late on September 1, the crew was ready to lift the first glass section of the lens. To protect all the careful repairs, the lens sections were raised in their crates. At the top of the tower, the crew pulled each glass and brass section out of its crate and signaled the tractor to lower the empty crate. The lens section was placed upright and secured to the pedestal with the original brass bolts.
Numbered by the Paris manufacturer, each lens section was raised in the proper order and bolted to both the pedestal and adjacent sections. Finally, only the glass door to the lens, used by the keepers to light and maintain the lantern, had to be placed. As Bob Bolen tightened the last brass bolt, smiles broke out in the lantern room and a radio call announced to the crew below that the Devils Island lens was home.
This summer, the first of many future generations of visitors will climb the stairs of the Devils Island Lighthouse, following in the footsteps of generations of keepers, to view the historic lens as it resumes its original position of vigilance over western Lake Superior.
What a great story! Join the Society and find out much, much more!
Wisconsin
Marine Historical Society
814
West Wisconsin Avenue
Milwaukee, Wisconsin 53233-2385
phone 414.286.3074
email info@wmhs.org
