Oh wow, that's my site. I found that photo in 2007 in an old Horse Soldier auction brochure. The description in the brochure was:
This veteran non-commissioned officer (NCO) is seated at a small table and wears his uniform of a dark blue Union frock coat adorned with the distinct, brass buttons of the Ordnance branch, over a sky-blue vest accompanied with dark blue trousers. The soldier's rank is clearly indicated by three chevrons of silk or worsted binding 1 /2" wide with a large silk star sewn above the elbow on both sleeves of his uniform coat. The sergeant is a professional soldier who served continuously for more than thirty years in the military as indicated by the six, diagonal, half-chevrons sewn to both his sleeves. In addition, the artilleryman has a 1 /8" wide stripe on each side of the chevrons that indicated wartime service. All NCOs, musicians and privates who served faithfully for a term of five years wore a single, diagonal, half chevron, 1 /2" wide that extended from seam to seam with the front end nearest the cuff. For every subsequent five-year term of service, the soldier was allowed to add a half-chevron above and parallel to the first. This seated, unidentified Ordnance NCO exhibits six such marks of distinction for service. He looks out at the camera and his eyes project a hard, but almost melancholy expression as one soldier who has 'seen the elephant'. The NCO has a large forehead that is balanced with a dark, full chin beard. On the table at his side rests his left elbow as well as his chasseur-type kepi. On the backside of the tintype is affixed a green, two-cent Internal Revenue stamp that is hand-canceled in black ink and dated 1864.
An Ordnance Sergeant does not belong to the Ordnance Department, but to the non-commissioned staff, unattached, of the regiment or post. So the uniform would be Infantry, not Cavalry.
I created that site to try and identify the Ordnance Sergeant in the picture. So far I have only identified three Ordnance Sergeants with at least 30 years but less than 35 years of service in 1864. One of those three is my great-great-great grandfather. He fought in four named wars: Texas Revolution, Second Seminole War, Mexican American War and the US Civil War.
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