In 2000 I had the pleasure of documenting the disassembly of a first-order Fresnel lens at the Franklin Institute, in Philadelphia, Pennsylvania, as part of an exhibition gallery renovation conducted by C. Erickson and Sons, Inc. The lens had been on display since 1933 when it was lent to the Institute by the Department of Commerce whose Bureau of Lighthouses oversaw lighthouses at that time. The lens had once served Fire Island Lighthouse on Long Island.
Fire Island Light Station was established in 1826-27; a second tower was built in 1858 and a first-order Fresnel lens installed. First-order lenses are the largest of seven orders of Fresnel lenses. They were used at coastal lights that needed to be visible to mariners from great distances. Fire Island was seen by traffic sailing into New York Harbor.
According to a Notice to Mariners dated July 3, 1858, the light was first displayed from the new first-order lens on November 1, 1858. Its characteristic was “a brilliant flash once every minute. . . . The new light should be seen in ordinary states of atmosphere, from the deck of a vessel 15 feet above the water, from 21 to 23 nautical miles.” The new lens created a much brighter light than the reflector system it replaced. The lens revolved around the light source by means of a rotation mechanism powered by weights which would be wound up by the keeper on a regular schedule.
A campaign by steamboat companies and marine-insurance companies was launched in 1908 to increase the intensity of the light. Their petition stated,
That it is of the greatest importance to the safety, and the uninterrupted course, of navigation that the light on Fire Island should be of a character equal to that of the best lights in existence elsewhere; That the present light on Fire Island has not been changed for many years, is not a modern light, and is not of such power as should be provided in this important position.
The U.S. Light-House Board recommended that Fire Island be equipped with a “modern high power illuminating apparatus” in its 1908 annual report, but no immediate action was taken. In 1929, the Office of the Superintendent of Lighthouses noted that “…the present apparatus is an obsolete type and beyond economical repair; it has been giving trouble for several years and has now reached the point where replacement is necessary.” In June 1933, the old first-order lens was transferred to the Franklin Institute and the Fresnel lens from the discontinued Shinnecock Bay Light Station replaced it. Because it could rotate more rapidly, the Shinnecock lens produced a flash at more frequent intervals and thus was of more use to mariners.
Museum records at the Franklin Institute, indicate that the Fire Island Lighthouse lens was first displayed on the ground floor of the Franklin Institute on June 10, 1933. The parts not used were stored at the Lafayette School (this probably included the spider and the weights) on November 10, 1943. The vapor lamp was placed in the lighting exhibit in 1964 and is now part of the Electricity Gallery.
According to an article in The Institute News (August 1938)
When the lens now to be seen on the ground floor was in active service, it was operated by the accurate clockwork which still runs it, except that a tiny electric motor has been substituted for the elaborate system of weights which ran down a tube through the middle of the lighthouse, around which a spiral staircase ran. These weights required rewinding every four hours.
The article also describes the installation:
The great lens, weighing between four and five tons, was brought to the Institute in pieces in 1933. It was first assembled in sections in the old Franklin Institute’s workshop, so that it might be checked up. It was then again disassembled, and brought to the new museum for its final assembly. When it was put together, it was found that there had been a miscalculation in the height of the ceiling, and that there was five-eighths of an inch less than had been anticipated. The result is that, at the present time, there is just about one-quarter of an inch clearance at the top of the huge lens.
It took nearly a week for lampists Joe Cocking, Nick Johnston, Jim Woodward, Jim Dunlap and Tony Farr and to disassemble and pack the lens components. Lighthouse Preservation Consultant Cullen Chambers assisted. NPS conservator Gretchen Voeks inspected every panel for damage and documented needed repairs. All the panels were carefully packed into crates for a long-time storage. We felt some regret at seeing such a beautiful artifact disappearing from view. So years later I was thrilled to learn that the lens was returning to Fire Island. In 2012 I visited Fire Island and had the chance to admire the lens once again in its new exhibit building next to the lighthouse.
Although the lighthouse grounds received much damage from last year’s Hurricane Sandy, apparently the lens came through unharmed. For more about Fire Island Lighthouse, visit their website.