I don't know how many different artists have illustrated a version of Black Beauty since it was first published in 1877. It may be the children's book with the most editions. I have read that the Bible is the only book that has sold more copies. It's popularity is a testament not only to the quality of the book, but also to the scores of animal lovers in the world. Anna Sewell told a story that needed to be told -- after all the centuries of servitude the horse has given mankind. It lives on today as a reminder to be kind to all living beings.
Every time I see a version of Black Beauty at a book sale, I buy it. Here are some interpretations:
Perhaps my favorite Black Beauty, by Wesley Dennis. Very soft, fluid. The perfect illustration for the narrative, "I remember a large pleasant meadow."
The Walter Seaton Black Beauty, nice.
Cute Black Beauty art for young readers -- Wonder Book's BB with a little girl by George Santos
Samuel Lowe's BB with a boy by George Pollard
Distinctive style of Fritz Eichenberg
And a "modern times" black Beauty by Susan Jeffers. Love her dreamy style, lots of attention to surrounding details. Nice lines.