I have found no period description of their uniforms. I do have some information on their uniforms, but exactly what they wore is open to discussion. I know that starting with Battery B, the State issued artillery uniforms to artillerymen, but have never found any information on the Loomis Battery geting any State issued uniforms. Three possibilities seem most probable. One, they wore their pre war gray fatigue uniforms. Two they were issued State infantry uniforms like those issued 1st Three Month Infantry Regimen. After all, they were to be attached to that regiment. Three, the State had artillery uniforms made for them, but no record of this exist.
A Detroit Free Press article of September 1 1860 gives their uniforms as blue dress coats coatees and blue pants trimmed red. Blue regulation caps (likely light artillery Ringgold caps) with red fountain plumes were worn. The fatigue uniforms were gray jackets, gray pants and gray caps.

When they were photograph at Fort Wayne in 1861, preparing to leave the State, they were wearing dark likely blue but possibly dark gray nine-button jackets with standing collars and matching epaulets. The photograph also shows dark trousers and dark kepis. The kepis are in the style of what is referred to as the “cadet pattern’ kepi. This could have been either State issued artillery jackets or State issued infantry jacket identical to worn by the 1st and 2nd Infantry Regiments. It is also possible that this uniform is the companies pre-war gray fatigue uniform that for some reason photograph dark.

Because their uniforms look so much like the State issued 9-button dark blue infantry uniforms I am of the opinion that this is what they are wearing in the photograph. I do not believe that they are wearing their pre war gray fatigue uniforms because that the unit recruited many new men for the war and they would not have had the gray fatigue uniforms. I must caution you that once the dark blue uniforms for the 1st and 2nd Infantry Regiments were made up the State switched to identical uniforms but now in gray for the 3rd Infantry. So they could be wearing gray infantry uniforms. The problem I have with being in gray uniforms is that in known photographs of the gray uniforms the uniforms appear light in color not dark, but all the photographs of the gray uniforms were taken in a studio and the photograph of the Loomis Battery was taken outside.

I have included this description of the Infantry uniforms. Photographs of this original State issued 9-button dark-blue uniforms show a dark blue, somewhat loose, roundabout jacket with nine gilt buttons. Staff buttons, embossed with the State seal had been used by the State since the 1840s and these were likely used on the jackets. In the 1850s the Michigan staff buttons were said to be silver in color. The delivery of the uniforms for the First Infantry Regiment was delayed due to the buttons not having arrived.

The jacket skirts ended at the waist and were square cut. The jackets had tall standing collars, with a seam at the top and welting down the center of the collar. The jacket had matching epaulets, each secured by a small gilt buttons near the collar. The jacket appears to possibly have a low set slit pocket on the right. The sleeve cuffs were unembellished with possibly a stitched line near the sleeve bottom and without buttons (in photographs some appear to have two gilt buttons, but these are possibly these photographs were taken latter).

I hope this helps you. If you have specific questions I will try to answer them. I have photographs and additional information on the infantry uniforms.

Bill Carr