STEVE INSKEEP, HOST:
A collector and his family have donated more than 1,000 Civil War photographs to the Library of Congress. None of them are photos of famous faces; there's no General Grant here, no General Lee. These are photos of enlisted men who fought in the war, most of them unidentified now. Reporter Ramona Martinez decided to recover one soldier's name, and his story.
RAMONA MARTINEZ, BYLINE: He has crazy sideburns, a steady expression, and very clear eyes - maybe gray, maybe blue. There's a rifle musket at his side. He is a Union soldier in the Civil War. And the only thing we know about him is what we can see in a single photo.
TOM LILJENQUIST: Look at that look.
LILJENQUIST: Is he telling you something from 150 years ago?
MARTINEZ: I really want to find out what happened to those guys.
LILJENQUIST: It's amazing.
MARTINEZ: That's Tom Liljenquist. He and his family collect Civil War photographs of enlisted men. Tom told me to look closer at the photo in front of me. My first clue was there - right there, on the gun he was holding.
LILJENQUIST: Look here, at the very bottom of the stock; he carved the initial T period, A period.
MARTINEZ: T.A., his initials. Then, Tom pointed out details of the soldier's uniform - another clue. And that clue could lead me to his regiment.
LILJENQUIST: So are you going to try and identify him?
MARTINEZ: I sure was. So Tom sent me to New York, to see Mike McAfee at the West Point Museum. He immediately knew the regiment.
MIKE MCAFEE: You see that uniform - the short, blue jacket; the red vest, or actually, a shirt vest; the red trousers; and the red and blue cap - and you know it's the 14th Brooklyn.
MARTINEZ: Fourteenth Brooklyn. Now that I had the regiment, I went to the National Park Service soldiers and sailors database. There, I found four possibilities.
VONNIE ZULLO: Thomas Abbott, Thomas Adams, Thomas Ardies and Thomas Austin.
MARTINEZ: That's Vonnie Zullo. She's a professional researcher. I met her at the National Archives. We pulled the pension files and military service records of the soldiers. Very quickly, Vonnie ruled out two of the possible candidates: Thomas Adams and Thomas Austin.
ZULLO: One never actually reported to his unit, and the other soldier was in a band, and he was 35 years old and much larger.
MARTINEZ: And then there were two. One, Thomas Abbot, was around 5-foot-8. The other, Thomas A. Ardies, was about 5-foot-4 and a half. What we didn't know was the height of our mystery soldier. But there was one item in the photo that would serve as a yardstick. Back to the rifle.
SAM SMALL: We actually have in stock today, and available to us, a model 1855 rifle musket - the exact model that the soldier is holding in the photograph.
MARTINEZ: That's Sam Small. He's the brother of our researcher, Vonnie. Their family owns a military antiques store, called the Horse Soldier, in Gettysburg. He was able to help us calculate the relative height of the mystery soldier by setting up a test. We asked a store employee who is 5-foot-8 to re-create the pose in the photo.
SMALL: And the muzzle of the gun comes to approximately two inches or so below his shoulders.
MARTINEZ: That meant our mystery soldier was the shorter of the two - Thomas A. Ardies. So what happened to him during the war? Vonnie reads from his pension files.
ZULLO: While a member of the 84th New York Infantry, in the line of duty at Chancellorsville in the state of Virginia, on or about the first of May, 1863, he received a gunshot wound while in action.
MARTINEZ: But he was not killed. The archives show that after the war, he moved to Canada. His pension file says...
ZULLO: He was always considered a bachelor by all who knew him in the community, where he was widely known and most respected.
MARTINEZ: He got married, though, at age 75. And on his death certificate, his occupation is listed as gentleman. History mystery solved. Rest in peace, Thomas A. Ardies.
For NPR News, I'm Ramona Martinez.
INSKEEP: And you can see the photos for yourself, at npr.org.