by Doug Crowell and Kel Hancock
The so called Cave-in Pit on Mahone Bay's famous Oak Island has long been thought to be part of the original treasure works. This well-like hole, discovered in 1878, opened up suddenly when a pair of oxen being used to plow a field, passed over the spot and the ground collapsed under them. Sophia Sellers, the daughter of Anthony Graves, and her husband owned much of the island at this point, and it was she who was handling the team of oxen that day. Speculation held that it was an air shaft created by the original workers while digging the flood tunnel.
According to one authoritative account:
“One day in 1878 Sophia Sellers had been plowing with a team of oxen when the ground had suddenly caved in under the animals and they had dropped into a hole six to eight feet in diameter and more than ten feet deep. The oxen were extricated and the incident forgotten until many years later when Blair saw the hole and heard the story from Sellers. What interested Blair and his fellow searchers was that the hole, which they dubbed the “Cave-in Pit” was about 350 feet east of the Money Pit and directly over the suspected route of the flood tunnel from Smith’s Cove.
Some investigators had previously suggested that a five hundred foot tunnel (from the Money Pit to Smith’s Cove) couldn’t have been built without having at least one vertical shaft somewhere along its course. This would have provided an additional point from which the earth from the tunnel could be removed; more important, it would have served as an airshaft for those digging the tunnel. Blair and his associates also suspected that the creators of the Money Pit might have installed a valve or gate somewhere in the flood tunnel, to be used to shut off the water when they came back for their treasure.
So the first job was to excavate and explore the Cave-in Pit. At a depth of fifty-five feet, seawater began entering it. By the next day the water was at tide level (about fifteen feet below ground level at that spot) and it couldn’t be lowered by bailing. That project was then abandoned. But the group was still convinced that the Cave-In Pit had been hand-dug at some earlier point, and there was no record of any previous searchers having put down a shaft in that particular area…
… Today the Cave-in Pit is a gaping circular crater one hundred feet deep and almost as many feet across. And the water still rises and falls with the tide.” - source: The Big Dig, D’Arcy O’Connor, Ballantine Books, New York, Nov 1988
There are two pieces of information that caught our attention in the above excerpt from D'Arcy O'Connor's excellent account of the Oak Island diggings. The first being Frederick Blair and associates suspicion that the cave-in pit being the site of a valve or gate to shut off the flood tunnels, and secondly, that there were no existing records of searcher work undertaken in that particular area. The idea of a gate to shut off the flood tunnel was gnawing away at some memory of a document I had seen during my research of Oak Island. I took some time and went back through piles of pages collected from various archives, and I quickly realized that I need a better filing system. There were many documents that I had no recollection of gathering up any longer. However, I did find what my mind was trying to get me to recall. The following is a document written in 1867, by Charles Ross, and outlines the plan for stopping the water drain on Oak Island.
Here is the transcript of the plan:
"Plan for Stopping the Water Drain on Oak Island
On the eastern side of Oak Island there is a cove, from which point it is said the water is let in by means of a drain to the shaft in which the “Kidd Treasure” is supposed to be.
The plan I propose to stop the water is to sink a shaft twelve feet across the drain and from two to three wide, from 100 to 200 feet above the cove. The centre of the shaft to come on the centre of the drain.
As soon as the shaft is taken down to show signs of water being near, the working must be stopped and the ground probed, which will be best done with an iron rod to find the drain.
The position of the drain being found, a gate must be made of iron as that shown in the enclosed plan, 2.5 inches thick at the top and going off to 1.25 at bottom. The sides and bottom of the gate must be steeled and made sharp. The length to be 8 feet by 7 wide. A driving shaft made of hard wood must be attached to the gate on top, and of length required.
The gate being made, take it and lay it near the western bank of the shaft, taking care to have the centre of the gate if possible coming near the centre of the drain, then drive the gate down until the drain is closed. This being done, put the pump to work and take the water from the Money Shaft.
If it is found that the quantity of water coming into the shaft is likely to give trouble, sink another shaft 20 or 30 feet back of the first, and drive another gate."
So here we have an 1867 plan for shutting off the flood tunnel from Smith's Cove. Notice that it is recommended that the shaft for this gate be dug 100 to 200 feet back from the shore. The exact location of the Cave-In pit is hard to determine now, as Robert Dunfield's excavation of that pit, created a much wider hole in the ground. By overlaying the Stephen March Survey of October 25 1937 on Google Earth, we can estimate that the Cave-In pit is located about 174 feet from the shoreline. This puts it within the parameters specified in the plan outlined above. What's more, the "75 foot" shaft, located between the shore and the Cave-In Pit, on the March Survey sits approximately 50 feet from the Cave-In Pit and about 123 feet from the shoreline. This puts both shafts within the parameters of the plan, and the plan states, "If it is found that the quantity of water coming into the shaft is likely to give trouble, sink another shaft 20 or 30 feet back of the first, and drive another gate".
We are not sure at this time as to when the "75 Foot" shaft as noted on the March survey was dug, but this excerpt from an 1863 letter shows that either the company was digging a shaft in that area, or they suspected a shaft in that area.
The Oak Island Eldorado Company shut down operations in 1867. Was the Cave-In pit one of their shafts, possibly created by enacting the above plan? Did they cover over the Cave-In Pit at the end of their operations, and eleven years later, Sophia's oxen cause the covering to collapse? Now that we know of the plan Charles Ross put forth, we now have a document that suggests that work was either carried out in that particular area, or had been planned for that area, so we now need to allow that the Cave-In Pit may have been the work of searchers. Here is hoping that further documents come to light, that will tell us more.
Goodnight from The Blockhouse!
From The Blockhouse
is published by Blockhouse Investigations and oakislandcompendium.ca
in Nova Scotia, Canada
Editors and Chief Correspondents
Kelly W. Hancock, CD
John Wonnacott, P. Eng.
All material and images published herein, unless otherwise credited, are copyright of Blockhouse Investigations and oakislandcompendium.ca and may be reproduced by permission only.
Views expressed in these blog posts are our own. The views of those that comment are their own.