Alleged flood tunnel from Smith's Cove

The Beach That Squeezed Like a Sponge

In 1850 the Truro Company, bailing the flooded Money Pit, noticed that its water was salt and moved with the tide. Sullivan quotes Jotham McCully, the company's manager, that as the tide ebbed the beach at Smith's Cove, on the island's east end, gulched forth water like a squeezed sponge. Crooker records what the shovels found: a two-inch bed of coconut fiber spread 145 ft along the shore, over rotted eelgrass, over clean beach stones laid where the clay had been removed. Behind a cofferdam the men uncovered five box drains of flat stones, about eight inches wide, converging like fingers toward the shore. The floor sloped landward, 5 ft below the old beach, when a high tide carried the dam away.

A shaft inland on the presumed line reached 75 ft without water. Twelve feet south a second hole struck a boulder at 35 ft; pried loose, it let the shaft fill to tide level within minutes, and stakes driven into the bottom changed nothing. Robert Dunfield's 1965 drain sketch gives the gradient near the shore: the drains join at 24 ft, a drain was plugged at 27 ft in 1850, Robert Restall met the water course at 57 ft, and the 1850 tunnel lay at 75 ft.

The Cave-in Pit, the Dynamite and a Mouth at 111 Feet

In 1878 the ground opened under Sophia Sellers's plow about 350 ft east of the Money Pit and took her oxen down fifteen feet. The Cave-in Pit sat on the line between drains and pit, and reopened in 1894 it took salt water at 52 ft. In 1897 the Oak Island Treasure Company, led by Frederick Blair, the Amherst insurance man, drilled five holes 80 to 95 ft deep on a line 50 ft inland, across the supposed course. Only the third struck water, at 80 ft, rising with the tide. A charge of 160 lb of dynamite in it set the water in both the Money Pit and the Cave-in Pit boiling, proof to the searchers that all three were one system. The flow did not stop.

That spring, with pumps holding the Money Pit at 110 ft, the crew found an opening in its east wall at 111 ft, two and a half feet wide, cut square in the clay and packed with beach stones, sea water driving out under pressure. Samuel Fraser of the Halifax Company had reported the same mouth at 110 ft in 1867. The water overran the pumps.

Bulldozers, Steel Walls and Red Dye

Crooker records that in 1965 Dunfield, the California geologist, bulldozed clay over the beach, after which the Hedden Shaft pumped clean water. The show took up the search in Seasons 6 and 7 behind a 525-ft steel cofferdam, extended the next year by a bump-out. The team found a triangular opening with a trickle of water matching an 1863 description of the drains, coconut fiber beside it, and reported red dye from a Money Pit borehole emerging at the cove. Cores between cove and pit showed four feet of loose sand in hard clay at 99 to 109 ft, matched to the 1897 opening. No tunnel was followed through.

The Geologists' Reading

Joy Steele and Gordon Fader, a marine geologist, read the facts differently. They hold that glacial till cannot carry an open four-foot tunnel over 500 ft, that gravel layers between the island's two tills conduct sea water inland as they do across Nova Scotia, and that the limestone, gypsum and anhydrite beneath are riddled with dissolved channels and sinkholes. On their reading the drains collected tar from a kiln and ended at the shore, and dye tests showed no channel to the pit.

What Is Mapped and What Is Not

The record supports an engineered beach with five converging drains, tidal salt water in the Money Pit, an opening in its east wall at 111 ft seen by two crews thirty years apart, and wet ground on the line between. Whether a cut tunnel joins them, or the sea finds its own way through gravel and dissolved rock, no one has dug far enough along the line to say.

Sources

• William S. Crooker, Oak Island Gold
• Randall Sullivan, The Curse of Oak Island: The Story of the World's Longest Treasure Hunt
• Joy A. Steele and Gordon Fader, Oak Island Mystery Solved, 2nd ed. (2018)
• Robert Dunfield, Field Sketch of Drain System (25 July 1965), and S. C. Fraser's 1867 report, as summarized in the site record