My guess is it was originally a foot-treadle driven lathe based on its apparent age, size, operational simplicity, and the miscellaneous attachments on the center of the leg set under the headstock.
IIRC, there was a company named "W.F. & John Barnes" that made fairly basic lathes back in the old days. It kind of appears to me that is what could be cast into the leg set under the tailstock.
Value?? No value as a metal lathe, but it could probably be used as a wood lathe with a few simple modifications. Beyond that, the two leg sets are probably the most valuable parts as they are in fairly high demand as "industrial retro" style furnishings as table legs etc. Check out this eBay listing:
http://www.ebay.com/itm/Antique-Roc...Industrial-Cast-Iron-Table-Legs-/331756493680
Your wife might love to have them in her "steam punk" themed boudoir!!