I'd been wanting to read this one for a while now, and I finally got a chance to purchase it on eBay a few weeks ago. Written in 1969, it stars Hardas Flint, the unfortunately named miner made of quartz from Powell's earlier crossover The Raggedys in Oz. With Glinda's help, he learns that his father Steely is being kept as a slave by the evil magician Peeramyd, who is using the tireless metal man to construct a tower to the stars. In some way, reaching the stars is supposed to help Peeramyd conquer the world, but it's not really clear how. Mr. Flint teams up with the Scarecrow and Tin Woodman to reach this tower, and they visit the typical assortment of odd communities, including an underground land where bankers go about their financial business despite it having no meaning and the friendly Tissue Town (I believe Powell worked for a paper company, and so probably had some knowledge in this area). When it gets strange is when Mr. Flint and Ozma pay a visit to the wizard Zon, who shows the two scenes from the history of Oz. According to this history, the Land of Oz was named after Ozma's grandfather Boz, which contradicts the Ruler's statement in Dorothy and the Wizard that there had been multiple monarchs named Oz or Ozma. What's even more troublesome is that, through Zon, Powell makes the Wizard of Oz a more sinister character. While there are some hints in Land that the Wizard usurped the throne from Pastoria, L. Frank Baum seems to have disregarded that by the time of DotWiz, and Ruth Plumly Thompson's Lost King makes it clear that Pastoria had already been enchanted by Mombi prior to the Wizard's arrival. In Zon's moving picture show, however, not only is Pastoria still around when the humbug shows up in his balloon, but the Wizard uses magic he obtained from Mombi to enchant Pastoria's wife Ozette, who is then given over to Peeramyd by the witch. The strange thing is, even though Ozette is rescued and the Wizard plays a role later on in the story, no one ever confronts him about his role in her disappearance. Even if Ozma decides to forgive the Wizard, she'd still presumably want him to answer for his crime. And it's not like she doesn't believe Zon; in fact, the text is clear that she trusts him implicitly. This really strikes me as sloppy plotting on Powell's part.
After the encounter with Zon, Powell takes a few pages to make fun of hippies. Actually, "make fun of" is far too light for his portrayal of the peaceniks as "carrying signs that protested against everything good." While there's certainly plenty about hippies that can be validly criticized, wasn't the main thing that they were protesting the Vietnam War? In what way could that have been considered "good"? I guess it's just something we'll have to chalk up to the time period, since I suppose the war was still popular in 1969. Looking at it from a modern perspective, though, it comes across as a rather bizarre political statement to find in an Oz book.
These points aside, did I like the story? Well, parts of it. Powell had a good knowledge of the Oz series and a clever imagination, which showed throughout the tale. Mr. Flint and the enchanted bird Quoztal were likeable enough characters. It was mostly just Zon who really struck me as being out of place. In addition to his contradictions of what Baum and Thompson told us about the history of Oz, Powell's presentation of him as basically a godlike entity in whom the others had to have faith didn't really seem appropriate for an Oz character. It was all too weirdly quasi-religious.