The Children's Blizzard by David Laskin

I need a neologism: it would describe the genre where one incident is used as a window to open a variety of topics. In this case, a blizzard in 1888 that killed hundreds of schoolchildren (the weather shifted abruptly in the middle of a school day, forcing children to walk home in light clothing) is used as the point of departure for an exploration of immigration to the Great Plains, meteorology, and the physical effects of freezing weather. All of these are interesting; Laskin's only misstep is spending too much bandwidth on century-old political infighting among government weather forcasters. But on balance, this was a very interesting--if heartbreaking--book.