It's not my favorite such book, since it's all sepia drawings and no color plates, but it is still very excellent. It's in relatively good condition though the spine is a touch delicate, and they didn't even have it in their higher-priced "vintage" section (which is still not THAT high priced -- it's like, secondhand bookstore prices, averaging $6 per book).
Also at the sale was a really pretty dark green 1906 edition of Call of the Wild, with really cool plates and one of those covers where they physically paste a color plate on it, for $6. But the spine was, again, delicate, and as neat as it was, I couldn't justify hardcover space for a story that exists infinite editions when I could use that space for an out-of-print one.
...I'm going to regret this decision, aren't I.