My Grandfather gave me this old Winchester

Hello gunnit, I was hoping some of you might be able to help. My grandfather gave me this old Winchester single shot chambered in .22 Short. Can someone give me any more information on it or if it might be worth something? The condition is pretty rough and antique firearms is not my strength.

http://imgur.com/a/E6pzy

Edit: Do any of you know what the wood piece is on the lever, I haven't seen that on any other 1885's. Does anyone have an idea of what it might be worth?

Thanks in advance everyone.