The book is meant to imitate the charm of Victorian children's literature in style. I found that it reminded me of books like At the Back of the North Wind and The Light Princess. Others have drawn comparisons to Alice in Wonderland. There are some beautiful passages and some very memorable lines, such as:
"It is well known that reading quickens the growth of a heart like nothing else."
That one may need to be painted into something to hang on my library wall...
For some reason, despite the beautiful writing, the plot of this one really didn't do much for me. I don't know why - everyone I know who has read it raves about it. One good reading friend even compared it to the Narnia books. And I totally trust the opinion of those readers, so I can't really explain why this one just didn't resonate with me the way children's fantasy usually does. I think it had to do with how meandering the plot was and how unimportant the main task September is given winds up being in the whole scheme of things. This charm for me was completely in the writing and not in the plot. I just didn't connect with it.
I recommend it for lover's of children's literature based on the writing style, which I loved, and the story, which I didn't love, but was loved by many trusted Reader Friends. I also recommend it to those who love Victorian-era writing: this is a great recreation of that style.