One place says 1876, another says 1886. I am inclined towards the latter, because it is cross-strung.
and the list of patents on the frame include one from 1881!
I noticed that too. Likely 1876 is a typo.
Keep in mind that it may have an Edwin Brown action, which most people would not be familiar with, and parts for it may not be available. Replacing it with a more modern action would be difficult.
I actually spent some time yesterday reading about Chickering. It's got a fascinating history. I found some videos about the Brown action on YouTube and found Jim Ialeggio's site where he talks about replacing the Brown action with a modern action for at least one of the Chickering's he's rebuilt. Then after some thought, I felt that it would be more appropriate to rebuild a historically accurate piano rather than modernise it. After all, there's plenty of good modern pianos to buy if one wants a modern action. Which then lead to thoughts as to how many rebuilders and technicians in the UK would be familiar enough to do a great job to restore this piano to it's original specifications! Any ideas Joseph?
A part of me really feels that this piano shouldn't be lost the past but I guess there's a lot of pianos where you could say the same. In my brief search yesterday I didn't see any other Chickering that had a similar frame either and wonder if anyone had any idea whether this piano is one of their better designs or not.