Making a traditional glass lens requires a lot of experience, skill, and patience grinding a piece of glass to the required shape, and is not for the casual experimenter. Making a glass Fresnel ...

Fresnel’s lenses let through 98% of the lamp’s output, which could signal ships up to 32 km away. By 1823, the lenses were appearing on lighthouses. By 1860, all lighthouses in the United ...

225-pound antique Fresnel lens that's guarded by two security systems. You'll also learn about the lighthouse's past inhabitants, like Tommy, who became known as "Pomham Light's Diving Cat ...

The lighthouse's lamps first burned whale oil and lard oil ... Its light — a third-order Fresnel lens installed in 1903 — was recently out of order for 18 months because of a mechanical ...

Seguin Island Light Station is the state's second oldest lighthouse and one of its tallest. The tower is notable for its rare 9-foot-tall first-order Fresnel lens that can be seen from more than ...