What was Sewell's purpose?

In the original introduction to Black Beauty that Sewell herself wrote, she seems to indicate that the purpose of the book is that of an equine care manual, and not that of an entertaining story. Education was very important to Sewell, and since she declared, in part, that her intent was to induce "an understanding of the treatment of horses" through her "little book," she had to explain how to treat horses. Consequently, it has been said that one could read Black Beauty and come away fairly well prepared to actually care for a horse.