"Could you dig down as deep as the Washington Monument goes up?" he asked. I thought perhaps I could, but I was a little doubtful for the Washington Monument seemed terribly high. “Men have dug wells many times as deep as the Washington Monument,” my father told me, “but never all the way nor nearly all the way through the World. You would have to dig many thousands of times deeper than the Washington Monument to get down even to the center of the World. It's eight thousand miles straight through the earth and most all the way is rock—just rock, and more rock, that's all." Then I gave it up.

"How do you know it's eight thousand miles if no one has ever been through the World?" asked the inquisitive child. I don't know what my father answered. I was too young to understand. I wonder if you are too young, if I tell you how we know it's eight thousand miles; for without ever having been through the World, we do know how far it is.