That was probably my most favorite book when I was learning to read. I still have the original 1960 hard-cover book that my parents bought for me ... it's a little raggedy around the edges, but it's still a solid book.
I saved several originals of my most favorite childhood books:
The Pushcart War
The Boxcar Children
All of the Hardy Boy books published before 1972
All of the Tom Swift books published between 1964 and 1971
Alan E. Nourse's "Raiders from the Rings"
Ben Bova's "The Star Conquerors"
Robb White's "The Secret Sea" (1968, which was the very first book that I purchased with my own money).
A lot of good memories on my bookshelves ...