For decades, adventurers searched for the legendary submarine. News of the discovery traveled quickly around the world. A ground breaking effort began to retrieve the fragile submarine from the sea. She was then delivered to the Warren Lasch Conservation Center, a high-tech lab specifically designed to conserve the vessel and unlock the mystery of her disappearance. The research was funded by Duke University, the U. Department of Defence, the U. Scientists uncover what killed crew of Civil War sub H.
Science Scientists uncover what killed crew of Civil War sub H. Hunley Scientists say they've solved a longstanding mystery about what killed the crew of the first combat submarine ever to take down an enemy ship. Social Sharing.
The Hunley itself later sank, with its crew of eight aboard. Had the men, for instance, suffocated inside the closed hull? I was reasonably certain that suffocation, a term that specifically describes lack of oxygen or cessation of breathing, would not have caused the deaths of the Hunley crew.
They could have asphyxiated, a more general term that would include the effects of carbon dioxide. Carbon dioxide is normally a tiny 0. As the percentage starts to climb, more and more CO2 is driven into the bloodstream. Receptors in the brain sense the increase in acidity and try to counteract it. The blood vessels on the surface of the brain dilate in an attempt to transport the acidity away from the sensitive neurons; this dilation causes a headache.
The brain increases the breathing rate and the heart rate and expands all the blood vessels, trying desperately to increase the amount of blood being pumped past the lungs so they can process and eliminate the deadly gas. In the end stages of carbon dioxide exposure, the acid in the veins begins to chemically break down the myriad enzymes and proteins that control bodily functions on a cellular level. After I used this information to create a three-dimensional model, my computer could tell me the size.
The crew would have had a to minute window of warning—depending on their levels of physical exertion—between the time the air first reached a noticeable 5 percent CO2 and when it reached the low-oxygen level of 6. Carbon dioxide causes pain; the headache is sharp and profound, and the ragged panting feels like the body is struggling to catch up after a panicky sprint. It was implausible that the crew would have stayed peaceful and quiet for this length of time during such symptoms.
I had surpassed the threshold of reasonable scientific evidence, and therefore, for me, the theories of suffocation and asphyxiation were eliminated. Once I ruled out those theories, I turned back to examining my primary suspect: the blast. The author Kurt Vonnegut once spoke in an interview about his time in the military in Germany during World War II, right after the firebombings that devastated Dresden.
His job had been to excavate the bomb shelters and basements to remove the rotting corpses before the entire city started to stink of human putrefaction. The people he found had usually died without moving, without any signs of struggle, and were often still seated in their chairs. They were not outwardly wounded; they were not blown wildly across the room. To a blast researcher, this scenario sets off all the mental alarms. Medically speaking, the injuries from an explosion are neatly divided into one of four categories.
A blast victim can receive only one type of injury, or they can receive a grab bag of trauma containing any mixture of the four. The injury types are numbered for easy reference: primary, secondary, tertiary and quaternary. The last three injury types are logical, meaning that they make obvious sense, and even people with zero blast experience can predict that they are expected possibilities.
In contrast, a primary blast injury—the kind possibly incurred by the victims in the Dresden bomb shelters—is a strange and horrifying fluke produced by the bizarre physics of an explosion. It is usually the result of a shock wave. A shock wave is a particular kind of pressure wave, and it can have a terrible impact on certain human tissues. It most commonly develops during an explosion, when molecules of air accumulated at the wave front are shoved together by the explosive gas urgently expanding behind them.
These molecules are so densely packed that they collide with one another far more rapidly than usual, generating a unique wave that moves faster than the normal speed of sound. If it were a car it would go from 0 to 60 in 0 seconds. When the pressure of one of these waves reaches a certain threshold, it can disintegrate everything in its path. Most of the human body handles fast-rising waves surprisingly well.
Such waves can move straight through water without causing much chaos and disruption, and human bodies are, after all, mostly water. In the chest wall, which is mostly water, sound moves at roughly 1, meters per second. In the lungs, sound waves have to navigate a labyrinth of air bubbles, and they slow down to 30 meters per second. Therefore, a wave moving through the body that hits the lungs is suddenly forced to slow down by 98 percent.
If a shock wave traveling through the watery tissue of the chest wall is like an out-of-control semi-truck speeding down a mountain highway, then lung tissue is the gravel pit of a runaway truck ramp.
The truck itself suddenly slows to less than 2 percent of its prior speed—but its great kinetic energy must still go somewhere. Cargo goes flying, gravel flies everywhere. Likewise, the delicate tissues that form the walls of the lungs rupture and shred, and blood sprays into the alveoli, the gas pockets needed for breathing. This breakdown is called spalling.
Brain tissue can also be affected by a shock wave, which can cause traumatic injury without ever damaging the skull. Critically, the brain remains intact after a primary blast injury, and the only potential sign of trauma is a faint inkblot of blood that may be spread across its surface. Fatalities from a primary blast occur at lower pressures than the pressure levels required to translate a human body.
To rephrase that in plain English: A person will die, choked with blood, from a shock wave that was far too weak to move him. I needed to go beyond my theory and actually test my blast idea, which meant I needed a model submarine and a body of water. The results were encouraging, but we needed to scale up and also conduct the experiment with black powder. My boyfriend, Nick, helped find a test site: an isolated, expansive tobacco, cotton and sweet potato farm with an artificial pond.
The owner, Bert Pitt, asked me to drive out to talk before he agreed to the project. Understandably, he had some questions. Sitting on barstools at his white kitchen counter, Bert and I looked at pictures of the Hunley on my laptop as I explained the project.
Unless they tried to eat the charge, they should be fine. The pond was beautiful, both in the traditional, picturesque sense and also in terms of my scientific perspective. I tried to suppress my joy and instead just firmly shook his hand. Nick decided he was up for a lengthy drive to a mysterious munitions warehouse deep in the country.
Brad Wojtylak, an agent with the Bureau of Alcohol, Tobacco, Firearms and Explosives, had called ahead so I could legally buy black powder in bulk. The warehouse was full of industrial shelving stocked to the brim with powder, ammunition, targets and security boxes aimed at helping doomsday preppers bury and hide their gold and bullets. We carefully lodged 20 pounds of freshly purchased black powder—the maximum amount permitted in one vehicle—in the trunk of my little Pontiac.
We were on the highway heading east when the car in front of us started spinning in erratic circles. I never saw what caused the accident. Something sparked the coupe two cars forward to hit the concrete barrier that divided our left-hand lane from westbound travelers. The coupe begun to turn doughnuts down the highway, catching the front end of the next vehicle in the line, metal and plastic and glass flying off like whirling shrapnel.
A moment before the chaos, I had noticed in the rearview mirror the grille of a massive truck pressed nearly up against us, and now my eyes were glued to the mirror despite the rapidly shrinking distance between us and the melee ahead. Nick had the same thought I did, and spoke only two words while digging his fingers into the handle of the passenger-side door.
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