Bayliss, Thomas 'Duplex Excelsior' c. 1880

This early Duplex Excelsior by Bayliss, Thomas has very nice details, like the open head, lock nutted spokes, rooftop shaped rims, plain bearings with brass oilers and rear wheel brake (applied by twisting the handlebars). Backbone is already hollow, but front and rear forks are solid. 
This model served as inspiration for the first American penny farthing, the Columbia Standard 

Bayliss, Thomas introduced this model in the 1870's, but in those years it was built with a long spring, pointing forward (see illustration, catalogue 1881) 
It was built at least until 1881 - including the rear wheel brake and lock-nutted spokes - to offer a cheap Bayliss, Thomas to the public. I can't exactly determine the age of this bicycle, but as it has the 'normal' spring, I would say 1880-1881.
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