This fantastic Cabinet card captures a Fireman in an old style uniform. He is seated in the photographic studio of Alex. Hesler of Chicago, Illinois. Note the pin on his bib that looks like a hydrant. Also note that his belt has some numbers and some writing. It would be terrific to have someone knowledgeable about fire department history to leave a comment explaining his uniform, pin and belt.
THE CABINET CARD GALLERY 
I feel your pain. I, too, have a cabinet card photograph of a volunteer fireman, wearing a bib-style wool shirt and a flat, billed cap. I’m trying to find someone to help me identify the company and the era of the uniform. If I find out anything, I’ll try to let you know. (The photo, by Julius Hebbel, is on my website.)
It appears that the belt’s lettering says “165 Precint…”