24-year-old James Gaylor, originally from Beaufort, North Carolina, worked with the Army Quartermaster Corps in Baltimore as a civilian. In the summer of 1863, while watching Union Army soldiers marching through Baltimore, Gaylor was hit in the left knee by a bullet fired by a gunman in the crowd:

In an 1896 pension file affidavit, Gaylor said:

… the wound of left knee I received while following the Army and working for the Quartermaster Department at $1.00 a day. I got that wounded knee on Pratt Street near Jones Fall Bridge while the Army was passing along the street on their way to Camden Station, and the shot was fired by someone on the sidewalk, but that happened six months before I ever enlisted.

Gaylor enlisted on November 23, 1863 at Worcester, Maryland, and mustered into  the 19th Regiment on December 25, 1863 at Camp Stanton. He worked as a Regimental Hospital Nurse where he came into contact with soldiers suffering from various contagious diseases. When he fell ill himself, he was sent to McKim’s Army Hospital in Baltimore where he was diagnosed with smallpox. On April 9, 1864, Gaylor was sent to the U.S. Marine Hospital in Annapolis where smallpox victims were quarantined until they recovered. 

In July 1864, Gaylor rejoined his regiment in time to participate in the Battle of the Crater outside Petersburg, Virginia. During the attack on the Confederate position, Gaylor's left wrist was injured by an exploding shell. His affidavit said:

I got that wound at the mine explosion in front of Petersburg, Virginia in 1864. I forget the day and month. The whole regiment was charging the Fort and just as I was trying to get out of the ditch while both sides were shelling, I remember a shell bursting up in the air and about that time I felt something strike me on the left wrist and was knocked down but not senseless. And I immediately got up and and went on with the rest of the company in the charge until it was over, and at the time my wrist was bleeding and cut nearly down to the bone, and had no feeling in it, and has not had much feeling in it since. I have never been able to straighten that hand out since, and prevents me from doing heavy work and lifting.

After the charge I went back to camp and I think Dr. Ransom, one of the regimental surgeons, sewed my wrist up and I remained in tent for about a week and then I was sent to City Point Hospital where I stayed for five or six weeks till the wound healed up.

When the regiment deployed to Texas, Gaylor served at the Post Hospital in Brownsville, Texas. He mustered out with the rest of the regiment on January 15, 1867 at Brownsville.