He drew a picture on a piece of paper, in which one line was inclosed by another, and remarked:
"The pencil mark on this paper is proportionately thicker than the crust of the earth over the earth cavern I have described. Even if it were made of soap suds, it could revolve through space and maintain its contour."
"But the earth is a globe," I interjected.
"You do not mean an exact globe?"
"No; it is flattened at the poles."
He took from his pocket two thin rubber balls, one slightly larger than the other. With his knife he divided the larger ball, cutting it into halves. He then placed one of the sections upon the perfect ball, and held the arrangement between the gas light and the wall.
Fig. 33.
A A, telescoped energy spheres.
"See; is not the shadow flattened, as your earth is, at the poles?"