Ordinary bike.
Judging by the shallow dropped bars and the fairly simple front wheel bearings, I'd guess that this is a machine from the early 1880s which has had both wheels replaced or re-spoked.
The rear wheel is clearly a (relatively) very modern replacement, and it's not uncommon to find these bikes with a totally replaced rear wheel, as the stresses imposed on them can be very considerable.
The front wheel appears to have it's original hub, which would almost certainly have been radially-spoked originally - the 'hairpin'-type tangental spokes are accomodated in holes drilled into the base of the flanges, which is something that I've never seen in 'original' tangent wheels. I suspect that you'll find evidence of the original threaded spoke holes drilled into the edges of the flanges.
The spring is a typical version of Harrington's Arab Cradle pattern, which was available in c.1885 in various configurations to suit both bicycles and tricycles (and, later, solid-tyred safeties), and this would probably have replaced an earlier leaf spring - there might be evidence of the fitting of some sort of bracket on the backbone, to encompass the 'tail' of such a spring, and the remains of it's original attachment at the head is evident in the close-up picture.