I found this at an antique store, a photo by C. L. Chester listed as in Saint Louis, Missouri. It was mounted on grey cardboard that is in a some what beat condition with some water stains and broken corners on the grey background board the photo is mounted on, so I reframed it. This is dated 1898, the description is "First infantry , Missouri National Guard, at Jefferson Barracks, Lemay, Missouri". At least that is what is written on the back in pencil. Not bad for $20. The frame cost more than the photo. I got a nice frame at Goodwill. The crazy frame store wanted $142.00 for a frame & mount.
From what I found, C. L. Chester also did steorview photos for Keystone & Underwood.
In this photo, the rifles are long Krags and the soldiers got tan Mills belts with individual cartridge loops. The best guys to view are the two sergeants shown in the close up photo. They also seem to have a large belt buckle. This all seems correct for the Spanish American War. The soldiers also seem to have leggings that come up almost to the knee. You really need a 20x loupe to see some of the details in the photo.
source: https://www.globalsecurity.org/military ... tia-mo.htm
Missouri Militia Regiments - Spanish American War
First Missouri Infantry.-Official title, First Regiment, Missouri Volunteer Infantry. Headquarters, Jefferson Barracks, Missouri. Organized (from the First Regiment, Infantry, National Guard of Missouri) and mustered in for war with Spain, May 13, 1898. Strength in officers and men for war with Spain not reported. Name of officer commanding during war operations not reported. Stationed during war: (1) Camp George H.Thomas, Georgia; (2) Jefferson Barracks, Missouri; (3) Armory. St. Louis. Casualties during campaign not reported. The regiment was mustered out at Jefferson Barracks, Oct. 31,1898.