I read this book decades ago, and have just recently recommended it to a young father to read to his children. It's a ripping good yarn about science, adventure, and fantasy. It's Tolkien for children with a modern slant. Wanting to reread it, I've found that the $2.50 I paid for it in 1975 has gone up to $50.00+, giving the young reader a clue to its popularity. I would recommend finding it at a library.
