At first man built twig huts in trees, but becoming better matched with his animal foes he took to caves and underground habitations. Our illustration of the latter shows a section through the soil. Lake dwellings marked a distinct advance. Other varieties of primitive habitations are the leaf hut, the tents of skin, the mud hut, and the beehive hut of stone. Roman villas are still models of beauty. American “skyscrapers” are peculiar to our time; but all early forms of dwellings, while marking progress, have existed contemporaneously throughout history.