If I'm looking at the Standard Catalog of S&W correctly, that is a .32 Safety Hammerless 2nd Model. Made between 1902 and 1909. It's chambered for the .32 S&W short. I wouldn't shoot it, but that's me. The top break designs aren't very strong, and usually start showing wear quickly. The next big reason is the nickel finish. It's very uncommon to see a gun of that vintage(or newer, for that matter) with an intact nickel plate finish....which leads me to pointing out the possibility of it having been refinished. If it is original, you've got a nice gun worth a few hundred bucks, maybe more at auction though.