Saturday, July 22, 2023

CSI: Nashville goes Civil War. Police 3D scanners and drones help plot trajectory of bullets fired on Sunnyside Mansion during battle

A mosaic shows likely trajectories of bullets fired by Union troops (MNPD)
What do police crime scene investigators and archaeologists have in common? It turns out, a lot.

Both take extreme care with evidence. They create detailed notes and photographs, make measurements and diagrams, then document and analyze the data.

These skill sets came into play when the Metro Nashville Historical Commission partnered with the Metropolitan Nashville Police Department to study two unoccupied log structures at Sunnyside Mansion in Sevier Park.

They wanted to solve the mystery regarding embedded bullets and holes discovered earlier this year in the cabin walls. The 44 “defects” – bullets, holes and chips – were associated with the December 15-16, 1864, Battle of Nashville, a significant defeat for the South.

Nashville police photographs of bullets, defects and removed projecticle
For Adam Fracchia, archaeologist with the historical commission, the ballistics project has provided an opportunity to learn more about the battle and its impact on the mansion. The house -- situated between battle lines -- was occupied for a time by Confederate pickets. Advancing Union troops fired upon Confederates in the log structures – made of stout cedar -- and used the residence as a hospital.

Sunnyside Mansion, the headquarters for the commission, has been undergoing an extensive restoration.

“I went and looked at the building and I noticed the bullet holes,” said Fracchia, who found more upon inspection. A forensics colleague suggested he reach out to the police department. “We wanted to get a (look at bullet) trajectory and where they were fired from.”

For Nashville police, the partnership was an excellent way to further test their FARO 3D scanners, which were used in the investigation of the 2020 Christmas Day bombing in the city. The scanners take 360-degree measurements and capture other details from a crime scene. (Photo courtesy of FARO Technologies)

Taking advantage of modern technology, police merged the scans with images they took by drones to make a mosaic of the mansion – which was built in 1852 – and show likely bullet trajectories and direction.

The project was only the second time that the department combined FARO and drone data, said Officer Douglas Belcher of the crime scenes detail.

“This gave us a great opportunity to test the technology we have and we think it did very well,” Belcher told the public during a July 13 presentation in the visitor center at Fort Negley, a large Union defensive fortification.

Another disastrous battle for Confederates

Nashville fell to Union forces in early 1862, relatively early in the Civil War. Tennessee was a strategic location for the Northern army and it built defenses in the capital.

Following a disastrous loss at the Battle of Franklin in November 1864, Confederate Lt. Gen. John Bell Hood moved upon Nashville, digging in below the city. Federal Maj. Gen. George Thomas attacked about two weeks later, sending Hood’s battered army off the field on Dec. 16.

The property now in Sevier Park is in the middle (click to enlarge map)
It has long been know that dozens of bullets, including Minie balls, were left on the porch door and columns on the big house at Sunnyside. Fracchia says you can still see evidence today.

The bullets and bullets in the log structures were found in February as restoration work reached that area on the north side of the house.

Until the damage was found, officials did not know whether the structures might have been elsewhere on the property before being moved to the house. Fracchia theorizes they may have been used as a kitchen or other ancillary purposes. Evidence of cabins for enslaved persons has not been found.

The north face in the 1980s and now (red is the area of study)
By the time of the Civil War, log structures were not fashionable and siding would have covered them, the archaeologist said. “The bullets likely went through the siding and they probably replaced the siding and the bullets were covered up.”

Fracchia said officials don’t have detailed descriptions of what happened on the property during the battle, but they believe Confederates must have been a significant target because of the number of bullets and holes. They eventually were forced to retreat.

Siding still covered the buildings when restoration began. “The more siding we took down, the more we found,” Fracchia said.

Crime scene unit logs entry points with rods (MNPD)
Old school and high tech meet

The police crime scene unit’s work at Sunnyside Mansion wasn’t all fancy gadgets. Officers did old-fashioned work first, marking and photographing the “defects” and using handheld rods to help determine trajectory and origin. An angle finder helped plot direction of impact – from the “leading edge” of the bullet. All of this information, including labeling of the defects, was used to complete the analysis.

“The goal is we want to determine origination. We are trying to figure out where the bullet came from,” crime scenes investigator George Bouton told the Fort Negley audience. “Bullets are predictably unpredictable,” he said. Flight paths are dynamic, including the effects of gravity on trajectory.

Police found and marked 44 bullet "defects" (Image MNPD)
Fracchia told the Picket that at some point after the battle, someone had chiseled out some of the bullets before the siding was replaced. “Nobody in active memory knew there were bullet holes in that wall.”

The archaeologist said a total of seven bullets were embedded in the two log structures. Most remain in the larger of the cabins. The smaller cabin, unfortunately, had to be taken down after the police examination because of its poor conditions. The logs have been kept.

The presentation included photos of a three-ring Minie ball and a Williams cleaner bullet.

“We are assuming they are Union bullets, given they were coming from the north, and fits the battle.” Some of the shots fired upon the mansion also came from the northwest.

The two embedded bullets mentioned by police are soft and burrowed themselves into the cedar. They are fairly well lodged in there, Fracchia said. “We don’t know exactly how far they were fired from.”


Officer Steven Jones said the logs had the density of railroad ties. “So it was extremely good cover.” He said most of the bullets were likely .40- or .50-caliber. "
It seems to be a heavy concentration of fire in one area.” 

While Sunnyside Mansion is not a crime scene, it was an interesting opportunity for the police department to employ old skills and new technology.

“The last time a human touched this was in 1864,” said Bouton. “It has been that long. It is still right there where it ended up.”

Maps of Federal attack and Southern positions and bullets (MNHC)
More research at site lies ahead

There’s more work ahead, but the project already is helping flesh out details of the fight around Sunnyside as Union forces swept in from the west and north.

“We see a much more complicated picture out of the battle and how it actually played out,” said Fracchia. “It was crucial to tell this part of the Battle of Nashville.”

The commission has found rifle pits and entrenchments on the land. One pit was found this spring when crews were digging a new sewer line to the mansion. “They hit a discoloration in the soil.”

“The soil was burned and there was charcoal. We found melted lead and two percussion caps.” Fracchia (left) said it was evidence of a small fire. “It was very cold during this time period.”

A researcher from Louisville, Kentucky, is doing dendrochronology work to determine the age of the logs.

“We are working on researching what else these bullet holes may tell us,” said Fracchia, adding he may do metal detector surveys and research the site using geophysics. (Metal detecting is illegal on any city property, including parks, he said).

The aim is to tell a wider story and put up interpretive panels next year after the renovation. The archaeologist would like the surviving cabin to have a few places left open so that visitors can see bullets, holes and chinking between the logs. (The holes would be protected by plastic or thick glass.)

Sunnyside Mansion was built in 1852 and it included outbuildings
Fracchia’s work experience has included archaeology in the East, including Baltimore, and forensic aviation archaeology -- he has helped identify fallen US service members overseas.

His goal in Nashville and Davidson County is to build awareness “that could lead to stewardship and ownership and preservation.”

“What is really surprising is the depth and interest in history and the fragility of these resources. We don’t know that they are there until we find them.”

Editor's note: Please contact Adam Fracchia at adam.fracchia@nashville.gov if you have questions or want to join the work on site.

One of the bullet holes tested in a log structure (MNPD)

The rear of the log structures; the one on the right has been removed (MNPD)

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