HILLSBORO INLET LIGHTHOUSE

The lighthouse was built in 1906 by the Russel Wheel & Foundry Company in Detroit, Michigan. Shipped in crates down the Mississippi River on US Lighthouse Establishment tender ships, it sailed to Miami where it was loaded onto barges and brought up the Florida East Coast Canal. It is 1 of 4 skeletal cast-iron lighthouses in this model. Barbier, Bénard & Turenne in Paris, France, created the lens system. The 2nd order Fresnel lens, 9 feet in diameter and weighing 2.5 metric tons, floated on mercury. The kerosene vapor light system burned about 1 gallon each night. Flashing once every 10 seconds, the lens turned via a clockwork mechanism where a weight descended through the tower and a keeper wound it up about every 90 minutes. In 1932, the first electric bulb was installed, and the flash slowed to once every 20 seconds. The flotation system failed in 1992, leading to the mercury being removed and a ball bearing rotation system being installed. In 2021, an LED system lit the lamp, giving it a visible range of over 28 nautical miles, making the lighthouse one of the brightest active aids to navigation in the world.