Out of the Silent Planet, by C.S. Lewis. Wonderfully written, though not as completely fleshed-out as a modern sci-fi reader may be used to. Still stands on its own two feet, worth a try. My first sci-fi. The Golden Bough, Frazer. Sublime, frustrating and intriguing. Changes your dreams, whether you immediately realise it or not. How Things Work: The Universal Encyclopedia of Machines. My grandfather gave me this when I was 8, I still regularly leaf through the tea-coloured pages and detailed black-and-red drawings two decades later. It's a charming book, the kind of thing we have websites for nowadays.
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