During the Civil War, George Washington’s Ferry Farm was the site of Union Army encampments that included some defensive works like a trench dug into the crest of the ridge overlooking the river.  In that trench and throughout Ferry Farm’s landscape, Union soldiers lost and threw away a wide array of military gear and personal belongings, which our archaeologists frequently excavate.

This blog post highlights an intriguing artifact excavated from the trench: a diminutive glass bottle.  This bottle is not so much interesting because of what it is – it’s a very common medicine style bottle for the mid-19th century– but rather what’s inside.  Clearly visible within the bottle is a hard black substance and for years we’ve wondered what the substance may be.

Enter Ruth Ann Armitage, our amazing chemist friend from Eastern Michigan University.  Over the years, she and her colleagues have generously used their extremely fancy equipment to analyze many of the residues we’ve recovered archaeologically. So we chipped off a little fragment of the substance in the bottle and sent it to her lab.

The sample was analyzed using scanning electron microscopy (SEM).  SEM works by shooting a beam of electrons at the sample, which gives you an image of its surface topography.  Backscattered electrons (BSE), collected in a different detector, tell you about the elemental composition.  In a BSE image, the contrast in the image is related to the atomic number of the material, with brighter areas showing high number elements (usually metals) and darker areas representing low number elements (like carbon). X-rays are also produced when the electron beam hits the sample, so an x-ray detector allows the chemist to do energy dispersive x-ray spectroscopy (EDS) to map out specifically what elements are present in the sample.  To put it simply, all of these techniques are good at alerting the chemist to the elements within a residue.

Our sample was also run through DART (direct in real time) mass spectrometry.  This technique is good at detecting organic components within a substance.  It’s important to note here that this is not an episode of CSI and a reading does not automatically tell you what is in the bottle.

That being said, almost immediately, Ruth Ann responded and we weren’t disappointed: “Did you know there’s mercury in this?”  Nope, we did not.

However, this discovery was not too surprising given the use of mercury in many medicines for thousands of years.  Now a days it’s common knowledge that you shouldn’t drink mercury…or touch it…or inhale it.  Believe it or not many people did not accept mercury’s dangers until well into the 20th century.  Some people born in the 1980s and before might even remember playing with the little balls of mercury from a broken thermometer, am I right?  As weird as it seems this wasn’t that dangerous because mercury is not toxic in such small concentrations.  However, if you were born a little further back you may remember a substance called calomel (mercury chloride), which was marketed as a cure all. Perhaps most tragically, it was as a common teething medication for children until the 1950s.  For a long time, mercury was seen as a potent healing metal and it was readily rubbed on skin, consumed, and vaporized for immediate effect on the lungs.

And while all of these treatments using mercury did little to address the body’s medical problem, mercury still caused an immediate bodily response, which convinced people it was working to cure their ailments.  When applied topically, it burned. When introduced into the body, it caused a person to sweat, salivate, and have diarrhea. The mucous membranes also went into overdrive, leading many to believe that the bad stuff in your system making you sick was being purged by the mercury.   The reality, of course, was that the body was trying desperately to rid itself of poison, the mercury.  That being said, mercury does actually have a place in the medical world and can be useful, it just took a little while for people to learn how to properly utilize it.

So, if the residue inside our bottle was medicine, what medicine was it?  Initially our archaeology lab thought it was calomel but the chemical analysis didn’t show any chlorine.  The most interesting components were mercury and sulfur, which could possibly indicate cinnabar, the ore from which mercury is obtained.  The image below is a close up of the mercury and shows the sulfur (dark circles) surrounded by the brighter mercury.

Other elements detected include carbon, oxygen, and trace amounts of iron, silica, and aluminum.  A closer look at the DART analysis suggests that the mercury compound might be in the dried remains of a fat or oil based on the presence of substances that form when fats decompose over time.

What does all this mean?  Unfortunately, without more research, it’s hard to say what was in the bottle other than the basic components already detected.  Because it’s a medicine bottle, our assumption is that the residue it contains was a treatment of some sort in which case we’re dealing with a soldier who had an ailment.  Common Civil War-era uses for mercury-based medicines were treating skin sores and lacerations, internal and external parasite infections, syphilis, and constipation, to name but a few.

What is even more interesting is that a nearly identical bottle which also contained a hefty amount of mercury was recovered across the river just a few years ago by Dovetail Cultural Resource Group from another Civil War context.  Read more about their discovery here.

Soldiers throughout history are known to have carried their own medicines with them so it’s very cool to see actual physical evidence of that.  As to the exact medicine, perhaps we’ll know someday but for now let’s just say it was definitely bad medicine.

Mara Kaktins, Archaeologist
Archaeology Lab Supervisor