I think this is a portrait of Mrs Gaskell which is signed by Charlotte Bronte as a mark of ownership. There is a thank you letter from Patrick Bronte to Mrs Gaskell in which he thanks her for a gift of a portrait. According to two respected Bronte scholars, the portrait was presumably of Mrs Gaskell. The comparison image is from a book owned by Wheaton College and is in a book owned by her husband Arthur Nicholls and inscribed by Charlotte. I think this shows that Mrs Gaskell and Charlotte were close friends.
Comments
The size of what appears to be the word "Bronte" is very tiny. It is 8mm. It is also written in white paint. Click on "Show Image caption" to reveal the possible Bronte signature.