very cool..

i think the chain among other things would date this safety bike as pretty early, before 1/8" bushing chain (patent 1880) became standarized... also perhaps it was made before pneumatic tires (1888) were de rigueur..

i think safety bikes first started showing up in the mid 1880s so i'd say anywhere from there to the mid 1890s...

try getting in touch with some guys from the wheelmen.. they specialize in the early stuff.. try their message board @
http://www.thewheelmen.org/forum/default.asp