“As the moon cooled off, a great deal of water was taken up by the rocks, while crystallizing and thus chemically united with them, a great deal more was absorbed by them mechanically, by their pores, while a still greater quantity occupies large fissures and chambers, penetrating in all directions through the planet communicating with each other and connecting the interior waters with those of the exterior continent. The action of the water has greatly contributed, not only to the enlargement of the spaces in the interior continent, but to the creation of a pulverized soil and pleasing landscapes. The chambers that are inhabited, are of course all connected with each other, but besides these, it is quite certain there are great numbers of very extensive ones in the masses of materials that bound the inhabited chambers. Artificial tunnels are constantly being cut into these walls and so new countries are often discovered and connected with the rest and opened for settlement. In addition to those chambers that come down to the sea level the aggregate of the area of which I told you is about 800,000 square miles, there are vast areas situated at higher levels in the material, that bounds the sea-level chambers. These elevated areas are at all heights from one-fourth of a mile to four or five miles above the sea-level. There are known to be many above these, but they are not habitable, on account of lightness of the air. The elevated chambers are connected with each other, and with the lower ones, by means of sloping passages at all grades. In some cases chambers are located directly on top of the thick roof of others and are reached by long and circuitous routes. In a number of cases, the walls of sea-level chambers, after closing in almost together to form an arch over them, widen out again above and thus form other chambers above, and sometimes these stories continue one above another until the surface of the hump is reached, where the openings appear sometimes as channels, and at others, as circular craters.” “No doubt,” said I, “the craters that our astronomers see in such vast numbers on this side of the moon communicate with your interior continent.” “Yes they do.” “Then is it possible, that they sometimes see down to your interior habitations? They report some of these craters, as appearing to be many miles deep.”