The Research Desk · Behind The Hell Gate Treasure
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The Dutch called it Hellegat. Sailors had harsher words. Hell Gate is the tight bend in the East River between Astoria and Wards Island, roughly opposite East 90th to 100th Streets, where the tides of New York Harbor and Long Island Sound collide. For two centuries it was a churn of whirlpools and hidden rock with names like Pot Rock, Frying Pan and Flood Rock.
The toll was real. Historians of the 1850s estimated that about one ship in fifty that tried the passage was damaged or sunk, and that something like a thousand ran aground in a typical year. It swallowed warships too. One of them is a story for another day.
Taming it fell to the Army Corps of Engineers and General John Newton, who concluded the rock could not be beaten from the surface. Floating drill rigs kept getting rammed by passing traffic. So Newton went underneath. At Hallett’s Point off Queens, his crews built a cofferdam, sank a shaft, and spent seven years tunneling under the reef while mule carts hauled out the spoil.
On September 24, 1876, the reef was fired. Accounts put the charge at 30,000 to 50,000 pounds of explosives packed into thousands of drill holes. The key was pressed by Newton’s small daughter, Mary, her hand guided by her mother. Water and rock rose about 120 feet, and not a window broke on shore.
Then came Flood Rock, nine acres of reef in mid-channel. Nine more years of digging left it honeycombed with some four miles of tunnels. On October 10, 1885, Mary Newton, now about eleven, pressed the key again. Nearly 300,000 pounds of explosives went off at once before an estimated 50,000 spectators. Witnesses described a mountain of water lifting well over a hundred feet and a jolt felt for miles. It is often called the largest planned explosion before the atomic age.
The broken rock didn’t go to waste. It was later used to join Great and Little Mill Rock into the single island that still sits in the river.
Why it’s in my filesIn The Hell Gate Treasure, the reefs are still there. The novel’s scenes in the past unfold in a Hell Gate no engineer had yet tamed, so I wanted to know exactly what my characters were up against.
- U.S. Army Corps of Engineers, “The Conquest of Hell Gate” (New York District history)
- “The Hell-Gate Explosion,” Popular Science Monthly, Vol. 10 (1876)
- Charles E. Munroe, “Notes on the Literature of Explosives,” U.S. Naval Institute Proceedings (October 1885)
- “Removal of Hell Gate rocks,” Wikipedia
