There are endless stories of "ghost ships", and most people should have heard of them at one time or another. In fact, the inspiration for these stories originally came from a ship called the "Mary Celeste"! The sailing ship was discovered in the Atlantic Ocean in 1872. At that time, the ship was intact and could still sail normally, but there was no one on board.

There were no obvious signs of fighting, nor signs of burning or other similar explosions on the ship. Basically, the transported cargo and crew members' belongings were not lost.

However, the only lifeboat on the ship was missing, and the rope on the lifeboat was cut directly - which shows that the person who took the lifeboat was in a hurry.

△ The Mary Celeste created by the artist

By examining the ship's logbook, basic background on the ship was revealed:

The ship departed New York on November 7, 1872, planning to transport 1,701 barrels of alcohol to Genoa, Italy.

The captain is Benjamin Briggs, and the crew includes his wife and two-year-old daughter, as well as seven experienced sailors.

The last recorded time in the log was the morning of November 25, 1872 - which means that the ship had been drifting unmanned at sea for a full 10 days before being discovered.

The ship was discovered by the De Gradia, a full 400 nautical miles from its last recorded position in the log.

According to the laws at the time, as long as such unmanned ships (including sunken ships) were brought back, huge rewards could be obtained, so the De Gradia took it to the nearest British territory-Gibraltar.

The investigators at the time were very suspicious of the incident. They even believed that the crew of the De Gradia was responsible for the "ghost ship incident." However, after a three-month investigation, no evidence was found, and the investigation could only be concluded with "unclear results."

According to the description, bringing back the Mary Celeste was a very arduous task. The crew of the De Gradia should have received huge rewards, but due to public doubts, they ended up receiving only 1,700 pounds (about one-fifth of the total value of the ship and cargo), which was considered small at the time.

The story of the Mary Celeste inspired novelists from all over the world to create novels based on it, and spread the story of the "Ghost Ship" to household names.

△ Articles related to the mystery of the Mary Celeste

Now, more than 100 years later, the mystery of the Mary Celeste still puzzles the world. Why did the crew choose to abandon the ship while the ship was still intact? What happened?

Recently, some scientists used rigorous chemical laws and models to explain what most likely happened at that time. The culprit may be the cargo transported by the ship.

Nine barrels of disappearing alcohol

The Mary Celeste was transporting alcohol. Although all 1,701 barrels of alcohol were piled intact in the cargo hold, 9 of them were empty. At the same time, the ship's forward and stern hatches were open, and the hatch covers were scattered on the deck.

This is denatured alcohol - highly concentrated ethanol. It is impossible for the crew to drink it. Therefore, scientists and historians speculate that these 9 barrels of alcohol may have suffered serious leakage during transportation because of the use of red oak barrels.

"Alcohol leakage", this key information led to the most mainstream speculation of the "ghost ship" incident: alcohol volatilization caused a large-scale fire, and the crew finally made a wrong judgment and abandoned the ship.

The journey across the Atlantic was extremely arduous. The weather at sea was changeable, and the crew had to keep the cabin doors closed at all times to resist the rough waves that might hit at any time.

It was a cold winter when they set out from New York, and the alcohol in the barrels didn't evaporate too much, but as they entered the warm waters of the Atlantic, the alcohol evaporated more and more.

In other words, as the ship sails, the alcohol concentration in the air becomes higher and higher in the confined space of the cabin.

△ Ignition when flash point is reached,?canadasafetytraining.com

After the vapor produced by the flammable liquid mixes with the air, a flash ignition phenomenon may occur when it comes into contact with a fire source. The conditions for flash ignition are related to the concentration of the flammable liquid vapor in the air and the temperature.

As long as the temperature is higher than 13°C and the concentration of ethanol (alcohol) in the air reaches between 3.3% and 19%, it is extremely dangerous and may ignite with the slightest spark.

Therefore, the Mary Celeste may have initially flashed due to alcohol. The crew members were too frightened and entered the lifeboat under the command of the captain. However, in the end, the lifeboat had an accident and all crew members disappeared.

etc……

Didn’t we mention before that there were no signs of burning on the ship?

In fact, not all fires burn in the same way, and there are indeed “fires” in the world that leave no trace.

Why are there no signs of burning?

I don’t know if you have ever seen a performance in which a performer applies alcohol to his hands and then lights it. The flames burn on his hands and consume the alcohol, but the performer’s hands do not seem to be burned by the flames.

(Note that this is a professional performance and it is very dangerous for ordinary people to try it.)

In fact, the temperature of the flame when alcohol burns can reach 500℃-600℃. The reason why the performer's hands are not easily burned is mainly because the alcohol is mixed with a large amount of water, and the alcohol vapor is burned instead of the liquid on the surface of the hand.

The "fire" of the Mary Celeste was somewhat similar to this kind of burning, and it happened only in an instant, so it did not leave any traces of burning.

In 2006, Dr. Andrea Serra, a chemist at University College London (UCL), was one of the first to tackle the Mary Celeste's "traceless fire."

He used paper blocks instead of wooden barrels and butane gas to simulate leaking alcohol. When ignited by sparks, a huge fireball erupted.

But surprisingly, the pieces of paper did not turn black, and there were not even any signs of being burned.

Andrea Serra explains:

This is a pressure wave fireball. The instant heat of ignition evaporates all flammable liquids, generates huge pressure, and erupts into a spectacular flame wave toward the exit, but behind the flame wave is relatively cool air.

So, there is no smoke left behind, and there is no burning or charring.

Dr. Andrea Serra was the first to experimentally restore "traceless fire", and recently Jack Robotham and Frank Mayer from the University of Manchester have further advanced his experiments!

△ Jack Robotham (left) and Frank Meyer (right)

More accurate restoration experiments

The two of them built a 1:18 scale detailed model ship and simulated the weather the Mary Celeste experienced at the time. Of course, the flammable liquid was also used as the cargo carried by the Mary Celeste at the time - alcohol.

First, they sprayed ice-cold alcohol into the tiny cargo hold to match the temperature of the frigid conditions when they set off from New York.

They then triggered a wire, causing it to spark.

Nothing happened; the low temperature made the ethanol vapor concentration too low to ignite.

They then shipped the model to the warm climate of the Azores. They heated the ethanol in a water bath (simulating warmer seawater) and heated the wooden model with a gas heater.

They sprayed warm ethanol inside, and this time, a spark ignited the thick, volatile ethanol vapor, causing a violent explosion.

The force of the explosion blew the loose door violently open and flung it across the room, landing on the wooden deck just as the Mary Celeste had been when it was first discovered.

However, the flames disappeared just as quickly as they appeared, and no traces of burning or charring were found on the wood.

△ The actual burning moment in the simulation experiment

At this point, the mystery of the Mary Celeste has largely been solved.

Experiencing such an explosion, the crew who lacked chemical knowledge must have been very frightened because they were carrying so much alcohol, so they made the wrong decision to rush into the lifeboats and leave the ship.

In the end, he left an intact ship and a chilling legend to those who came after him.