Flood tunnels?

[chalkoutline]

Hello,
The topic of flood tunnels comes up followed by alot of back and forth so i decided to see if the theory of flood tunnels is possible using my new knowledge of boyles law to calculate hydrostatic pressure.

Using the attached diagram, here is what ive found...
1. From a previous thread, a ship arriving in May would have time to dig a 100ft vertical shaft during the dry season using half log platforms and no wall support.

2. A cofferdam could be built in Smith's Cove where a 2.5ftx4ft tunnel 360ft in length is dug using cribbing to intersect the shaft at about 100ft.

3. The shaft could then be filled by adding logs to make the half platforms full platforms and fill the entire shaft with till to the top.

4. Once filled, the cofferdam would be removed to allow seawater to rush down the 2.5ftx4ft tunnel. The water will compress the air in the tunnel and stop at 260ft creating an airlock between the water and the filled vertical shaft which has more than enough weight to hold back the hydrostatic pressure of the seawater. Only 20ft of till is needed.

5. They leave the island by September before the rainy season and still good sailing weather.

6. In 1803, the Onslow company digs to 93 ft before stopping for the night. At 90ft, there is no longer enough weight in the shaft to hold back the seawater causing the shaft to flood to sea level.

After analyzing all this, the money pit story seems quite possible; however, is it probable?

I personally don't believe it is...
if someone knowingly comes to OI to bury something 100ft down they would have planned on using cribbing throughout the dig (not just the tunnel) since they wouldn't know if the till would be stable for the entire 100ft and the possibility of bad weather.

If someone unknowingly came to bury something would not have dug that deep since they would have to retrieve it later.
-CO

 

[TruthbeTold]

Even with actual evidence from someone who ACTUALLY excavated on the island and proved that there were no flood tunnels, folks here still attempt to spin fictional theories about something that never existed.

 

[chalkoutline]

Even with actual evidence from someone who ACTUALLY excavated on the island and proved that there were no flood tunnels, folks here still attempt to spin fictional theories about something that never existed.

As you know i studied the Dunfield dig as did you and we are in agreement Dunfield found NO evidence of flood tunnels.

My diagram and calculations merely shows the story has been tweaked throughout the years such that it seems possible giving hope to those who believe!

 

[chalkoutline]

I hope this doesn't get to confusing...

To be fair i decided to show the Dunfield dig on my finger drain diagram from Smith's Cove which i now know to be on the east side of Oak Island. See attached diagram. Clearly he would have found the flood tunnel.

However, as i completed this diagram i immediately realized something was wrong.

I attached a diagram ive posted before. This diagram shows the Dunfield dig is southwest of the MP and NOT east between the MP and Smith's Cove.
So Dunfield was looking for the flood tunnels from the South Shore and when he didn't find any.

For some reason i thought he was looking for the finger drains and why i thought they were south and not east. It could be i hadn't heard about the 4 ice holes off South Shore yet.

Although I didn't study it too hard, didn't Dunfield also dig at the Cave-In Pit?

 

[GravelTeeth]

Although I didn't study it too hard, didn't Dunfield also dig at the Cave-In Pit?

The MacPhie/Wonnacott report I referenced in the other thread has some Smith's Cove data sourced from Dunfield, so he certainly studied the alleged finger drain area during his time on the island. To what extent I'm not sure yet.

This might be a good place to plop this doozy (assuming for the sake of argument that the transcript is legit -- haven't seen the source scan). Although I don't necessarily agree with the conclusions reached by Mr. John Brown within that correspondence, all such primary source documentation is enlightening. I think it was his opinion that uncribbed flood tunnels would have been doomed to collapse/subsidence shortly after their creation, and that even fully and "sturdily" timbered ones would not have stood the test of time. I believe the lore relates that at the MP end the flood tunnel egress was floored with beach stones, and "squared" at the top (perhaps implying timbering?) but not explicitly described as timbered or cribbed.

--GT

 

[pepperj]

Hello,
The topic of flood tunnels comes up followed by alot of back and forth so i decided to see if the theory of flood tunnels is possible using my new knowledge of boyles law to calculate hydrostatic pressure.

Using the attached diagram, here is what ive found...
1. From a previous thread, a ship arriving in May would have time to dig a 100ft vertical shaft during the dry season using half log platforms and no wall support.

2. A cofferdam could be built in Smith's Cove where a 2.5ftx4ft tunnel 360ft in length is dug using cribbing to intersect the shaft at about 100ft.

3. The shaft could then be filled by adding logs to make the half platforms full platforms and fill the entire shaft with till to the top.

4. Once filled, the cofferdam would be removed to allow seawater to rush down the 2.5ftx4ft tunnel. The water will compress the air in the tunnel and stop at 260ft creating an airlock between the water and the filled vertical shaft which has more than enough weight to hold back the hydrostatic pressure of the seawater. Only 20ft of till is needed.

5. They leave the island by September before the rainy season and still good sailing weather.

6. In 1803, the Onslow company digs to 93 ft before stopping for the night. At 90ft, there is no longer enough weight in the shaft to hold back the seawater causing the shaft to flood to sea level.

After analyzing all this, the money pit story seems quite possible; however, is it probable?

I personally don't believe it is...
if someone knowingly comes to OI to bury something 100ft down they would have planned on using cribbing throughout the dig (not just the tunnel) since they wouldn't know if the till would be stable for the entire 100ft and the possibility of bad weather.

If someone unknowingly came to bury something would not have dug that deep since they would have to retrieve it later.
-CO

Google Search

While your theoretical model utilizing Boyle’s Law and hydrostatic pressure calculations provides a fascinating mechanical framework for the "Money Pit" booby trap, several historical and geological factors suggest it is not probable as a man-made construction.

Historical and Engineering Constraints
The 1803 Onslow Dig: Historical accounts state the Onslow Company reached approximately 90–93 feet before water flooded the shaft to the tide level. Your theory that removing "weight" (the till) triggered the flood aligns with the legend, but critics argue the flood was likely a result of reaching the island's natural water table.
Stability Without Cribbing: You correctly identified a major flaw: digging a 100-foot vertical shaft in glacial till (rock, sand, and clay) without shoring or cribbing is extremely dangerous and prone to collapse. While the original legend mentions oak platforms every 10 feet, there is no historical evidence of side-wall support until later searcher efforts.
Construction Complexity: Building a 360-foot tunnel (2.5ft x 4ft) at a 100-foot depth using 18th-century tools would require advanced mining expertise, ventilation, and significant manpower. Skeptics note there is no historical record of such sophisticated "flood tunnel" booby traps ever being constructed anywhere else in the world.

Geological Counter-Evidence
Modern scientific studies offer more "probable" natural explanations:
Porous Geology: Oak Island is a
drumlin sitting on porous limestone and gypsum. These materials erode to form natural cavities, sinkholes, and "natural tunnels" that allow seawater to flow freely underground.
Woods Hole Study: A 1995 survey by the Woods Hole Oceanographic Institution concluded that the flooding was likely a natural interaction between tidal pressure and the island's underlying geology, rather than man-made tunnels.
The Dye Test: While some searchers claim dye proved a specific tunnel to Smith's Cove, other tests showed dye leaking from multiple points around the island, suggesting a general "Swiss cheese" geology rather than a single intentional trap.

Probability Conclusion
The "Money Pit" story is widely considered improbable due to the sheer lack of evidence for the tunnels' existence. Searcher Robert Dunfield excavated the area extensively in the 1960s and found no evidence of man-made flood tunnels, attributing the water to the natural water table.

There you have it, AI achieved the answers.

 

[mtdoramike]

To me, the only reason someone would bury something 100 feet deep and then booby trap it with flood tunnels is if they didn't want what ever they buried to be dug up. Like it had something evil attached to it, like a Dybbuk box or similar. Or it was always meant to be a distraction and they actually buried their treasure else where.