If John McPhee didn't actually invent the genre of the book-about-one-thing-from-all-angles (cf. [Cod:], etc.), then he wholly owns it. Oranges is an original, stemming from what was to be a New Yorker article back when he was a young writer. It's stuffed with fascinating facts about citrus - did you know that oranges can be chimerical, with single segments genetically different compared to the other segments? Or that some fruits "breathe" out a gas that can make an orange peel more orange? Or that different sides of an orange tree bear fruit with predictably different characteristics (such as sweetness)? Great stuff. A slender & quick read, too.