then he enthuses about coal. Consider a single piece glowing in your family's stove. See it, children? That chunk of coal was once a green plant, a fern or reed that lived one million years ago, or maybe two million, or maybe one hundred million. Can you imagine one hundred million years? Every summer for the whole life of that plant, its leaves caught what light they could and transformed the sun's energy into itself. Into bark, twigs, stems. Because plants eat light, in much the way we eat food. But then the plant died and fell, probably into water, and decayed into peat, and the peat was folded inside the earth for years upon years--eons in which something like a month or a decade or even your whole life was just a puff of air, a snap of two fingers. And eventually the peat dried and became like stone, and someone dug it up, and the coal man brought it to your house, and maybe you yourself carried it to the stove, and now that sunlight--sunlight one hundred million years old--is heating your home tonight . . .