Boston Lighthouse Fresnel Lens Massachusetts
Harbour Lights #665
Lighthed
 

Boston Harbor Light was the first lighthouse in America. The original structure was destroyed by British forces during the Revolutionary War and was rebuilt in 1783. Some 66 years later it was endowed with a beautiful and powerful Second Order Fresnel Lens. That same lens continues to greet mariners entering the Harbor, just as it has for 144 years.

The Fresnel Lens was in use in Europe for 20 years before it came to America. They were costly, and considered by some to be "a fad that is cost prohibitive." It was only after years of outrage by mariners that a congressional investigation resulted in an appropriation for our first Fresnel Lens. In 1841, the first Fresnel Lens was installed at Navesink Lighthouse, NJ, and in 1852 the Lighthouse Board was created. Only then did the great lenses begin to light America’s coastline.

In 1859, Boston Light was raised to its present height of 89 feet and was outfitted with the mighty Second Order Fresnel Lens. Built in France and transported in sections for reassembly in the lantern room, its 12-sided design, containing more than 1,500 hand-cut prisms, revolved on machinery that keepers had to rewind frequently. Keepers polished and cleaned the lenses with care, assuring that the complex configuration was always in top condition.

Originally, the great lens was illuminated with oil lanterns, which had to be refilled cautiously. Even so, small fires were common. When electricity became available, a single 1500 watt bulb was all that was required to be refracted by the lens and projected to mariners more than 16 miles off shore.

The Second Order Fresnel Lens stands more than 6-ft. high and close to 5-ft. in circumference. Its light is equivalent to more than 2-million candlepower. The Fresnel Lens is no longer in production -- replaced today by new automated technologies. This adds to the value of the lenses that are still in use, like Boston Light, and is a testimony to their durability.

Boston Light is the only officially manned lighthouse in America – the last to carry on a centuries-old tradition. The Coast Guard still maintains the priceless Fresnel Lens, just as their predecessors did, but with one advantage: they no longer have to extinguish it at dawn and relight it at dusk. The light burns brightly 24 hours a day, flashing its familiar signal, once every 10 seconds, to mariners and welcoming them to Boston Harbor.
 

Battery Powered; an optional AC adapter is available for $5.