Why has the Sandy Hook Lighthouse endured?
The Sandy Hook Lighthouse was the fifth lighthouse constructed in the American colonies, says Hoffman, out of a dozen that had been built by the time of the American Revolution. Over time, however, each of the others was lost—whether to war, storms, fire, coastal erosion, poor construction, or replacement by newer towers—leaving Sandy Hook as the only original seacoast sentinel from that early period.
U.S. Lighthouse Society historian Jeremy D’Entremont, who has written more than 20 books on early American lighthouses and maritime history, credits New York builder and mason Isaac Conro for constructing such a resilient tower. “He apparently used strong mortar,” D’Entremont says. “There are examples of early lighthouses where builders mixed salt water in the mortar, making it very weak. Many of the other early builders were not really qualified and had no experience building lighthouses. They were simply the low bidders.”
The lighthouse’s location also played a role: “In 1764, the lighthouse stood about 500 feet from the tip of Sandy Hook,” Hoffman says. “But ocean waves continued to bring more sand to the north end of Sandy Hook—and around the east, north and west sides of the tower, which protected it from ocean flooding and especially beach erosion.” Today, the lighthouse stands approximately one and a half miles inland from the northern tip of the peninsula.
What happened to the Sandy Hook Lighthouse during the American Revolution?
Rumors of an impending British invasion of New York raised alarms among local patriots in early 1776. Knowing that British vessels would rely on the Sandy Hook lighthouse to navigate the tricky sandbars and shoals leading into New York Harbor, a patriot raiding party struck on March 8, 1776, removing eight copper lamps and four casks of whale oil, and smashing the lantern glass to disable the light. Their success, however, proved fleeting. Just a month later, the British captured the tip of Sandy Hook, placed troops on land and warships just offshore, and had the lighthouse repaired by June, writes Eric Jay Dolin in Brilliant Beacons: A History of the American Lighthouse.
At dawn on June 21, 1776, Lieutenant Colonel Benjamin Tupper and 300 Continental soldiers moved surreptitiously to reach within 150 yards of the lighthouse in an attempt to take it back. But as Tupper wrote in a letter the next day to George Washington, commander in chief of the Continental Army, he had ordered “the artillery to play” against the tower for an hour, but “found the walls so thick as to make no impression.”
Continental forces made five more attempts to recapture the lighthouse—including on July 3, 1776, when they fired six-pound balls from two cannons. But the British would retain control of the Sandy Hook Lighthouse for most of the war.
What was the original light source, and how has it changed over time?
The Sandy Hook Lighthouse originally used eight whale-oil lamps, upgraded in 1827 to 18 oil lamps with parabolic reflectors, says D’Entremont. In 1857, this system was replaced with a third-order Fresnel lens, which remains in use today, and can project its beam up to 19 nautical miles on a clear night.
Invented in 1822 by French engineer Augustin Fresnel, the lens used hundreds of pieces of glass to concentrate scattered rays of light into a single powerful beam, dramatically improving visibility. Fresnel lenses were made in six sizes, or "orders," with first through third order typically used in coastal lighthouses like Sandy Hook to warn ships of nearby land.
Has the Sandy Hook Lighthouse ever gone dark?
In addition to the brief period during the American Revolution, the light was also extinguished briefly during the Civil War, and it was kept off during the Spanish-American War and both World Wars so enemy ships couldn’t get their bearings, says Hoffman. Hoffman, who has worked at Sandy Hook for more than 50 years, also notes that the automated light has gone dark several times in recent years as well.
