The Wheelmen.org manufacturers list has:
Miami-(M) Miami Cycle and Manufacturing Company, Middletown OH, 1906-1916
Miami-(M) Miami Cycle Manufacturing Company, Middletown OH, 1896-1898
From my limited experience, based on the geometry, stem, bars, saddle and metal fenders it looks more like 1916 than 1898. Is the rear hub a coaster brake or a fixed hub? some early coasters did not have torque arms. The make and model of the hub would really help narrow things down. Definitely worth fixing up to ride!