Object of the Month: A signed first edition of Anna Sewell's Black Beauty is described by Jenny Caynes, Curator at the Museum of Norwich at the Bridewell.

The Museum of Norwich at the Bridewell is currently exhibiting original watercolour paintings by artist Cecil Adlin who was commissioned by Jarrolds to illustrate a 1912 edition of Black Beauty. Jarrold & Sons had first published the book by local author Anna Sewell in 1877, and it is one of those rare first editions that we have chosen as Object of the Month.

The book, currently on display at the museum is a small and cloth bound with a red cover. But what makes this special is that it is signed by Anna herself; 'Helen Ada Sewell from her affectionate Aunt, Anna Sewell 1878'. Anna lived only a few months after the publication of her only novel, making inscribed copies very rare.

From 1867 until her death in 1878, Anna lived in 'The White House' at Old Catton with her mother and father and it was here that Black Beauty was written.

Anna Sewell first mentioned that she was writing Black Beauty in her journal on November 6 1871. She wrote 'I am writing the life of a horse, and getting dolls and boxes ready for Christmas'. Anna didn't write the novel for children. She said that her purpose was to 'induce kindness, sympathy, and an understanding treatment of horses' and wrote it as a kind of instruction manual for working grooms, coachmen, wealthy landowners and nobility. In Victorian Britain, all kinds of people worked with horses every day, and it was to each of them that Anna wanted to tell the story of Black Beauty.

But the fact that the book has become a children's classic shouldn't surprise us. It's a story full of emotion, narrated by the horse himself. Woven throughout Black Beauty's story are detailed descriptions of horse-care and practical-advice, and reflections on the world by animal and human characters alike. It is in this that we can see Anna's original intent, and the book becomes both a moving story and an instructional, practical guide.

The museum is playing host to this exhibition to mark 140 years since the publication of Black Beauty – a book which has sold more than 50 million copies worldwide and has never been out of print.

The exhibition highlights 13 beautiful watercolours by Cecil Aldin, which are on loan to the Museum of Norwich from Jarrolds. A contemporary of the famous painter Alfred Munnings, Aldin was a prolific painter of race-horses and hunting scenes in watercolour, as well as being a keen sportsman. From the quiet, charming scene of a young Black Beauty with his mother, to the tumult of a storm at night, Aldin's illustrations capture the essence of moments from the novel.

Although commissioned in 1912, the paintings lay undiscovered for many years until Richard Jarrold found 13 of the original 18 carefully stored in a box in 1982. The paintings have rarely been on show.

The exhibition Cecil Aldin – The Art of Black Beauty runs until November 25 2017.