Saturday, August 26, 2017

Rediscovering the H.L. Hunley [WaPo] [UNC]

On Thursday, the Washington Post reported on the unearthing of the H.L. Hunley, the fabled Confederate submarine that sunk in 1864 while assaulting a Union post during the Civil War. After 136 long years on the seafloor near Charleston, South Carolina, and then another 17 years after the sub's recovery in 2000, a team of researchers were finally able to figure out what sunk it.

The report contains a picture of the inside of the recovered H.L. Hunley, as it looks now. The closest comparison I can think of is a sewer with a skeletal tree branch running through it.

Here's the report.

University of North Carolina biomedical engineer Rachel Lance, assisted by the omnipresent co-author et al., couldn't find a reason for the crew's deaths on the sub, as the Post explains:

But when they ventured inside the boat, they found not a single clue. Its 40-foot-long iron hull was barnacle-encrusted but not broken. The skeletons of eight members of the crew were found still in their seats at their respective battle stations; their bones bore no evidence of physical harm. The bilge pumps hadn't been activated. The air hatches were closed. There was no sign that anyone had tried to escape.

The report and article demonstrate that the H.L. Hunley may have accidentally sunk itself by means of a pressure wave caused by its own torpedo. The pressure wave could kill without a trace:

Instead, when a torpedo blows something up underwater, it creates pressure waves that reverberate in the water and through the body of anyone who happens to be in it. The instantaneous increase in pressure can squeeze oxygen out of the lungs and pop blood vessels in the brain. The effects are often deadly.

But the damage occurs exclusively in a victim's soft tissue, like the gut, lungs and brain — from the outside, it can be impossible to tell that the person has been harmed.

On the plus side, if it can be called that, the torpedo sank the Housatonic, a Union ship.

The academic article also contains some really cool diagrams of the H.L. Hunley as it would have looked on its final voyage back in 1864.

Here's the article.

A couple interesting thoughts after reading that aren't answered by the article or the study:

1. The WaPo story is filed under "Science", rather than "History" or something similar. Where does such an inherently interdisciplinary article get filed? The study it cites was written by an engineer, which supports the "Science" label. Still, not every traumatic blast happened in 1864, and history books frequently focus on disciplines from artists to homemaking...

2. To what extent did the Confederacy or outside observers realize what had happened? The discovery is so new, yet self-defeating pressure waves apparently weren't such a problem 50 years later when submarines were standard fare during World War I. The Russian Empire's submarine program faced severe problems in the Baltic Sea, but they were still 55 strong.

No comments:

Post a Comment