Grandpa found this digging and it's one of those buttons he never really figured out. Considering it's an eagle on an anchor I assume it's navy? I checked Alberts button book and it wasn't under navy so hopefully one of you can help.
S.N. Meyer Company started in 1871 and advertised military buttons from 1894 through 1930 per McGuinn's book. Your button has a 19th century look to it IMO, but experts may be able to nail down a date range.