in that condition, not much hope, if you can accurately measure the length (at both ends) and diameter of the chambers it might help. Measurements need to be in 100ths of an inch so you'll need a digital caliper. There are just so many possibilities though, it'll be a hard one to nail down.
It appears to be a standard fluted five shot cylinder for a DA.32-.38 caliber pocket revolver. (S&W, H&R, IJ, etc...) Most likely post civil war period. NOLA Ken's advice will narrow down the caliber, but you would have to visually compare it to intact specimens to be close on the maker. Always cool to find, and maybe the frame and barrel are still at that "spot." Sub