Thoughtlessly turning over a boulder about nine inches square, lo! there was subject enough for thinking underneath it--a subject that has been thought about many thousand years; for this piece of rock had formed the roof of an ants' nest. The stone had sunk three inches deep into the dry soil of sand and peaty mould, and in the floor of the hole the ants had worked out their excavations, which resembled an outline map. The largest excavation was like England; at the top, or north, they had left a narrow bridge, an eighth of an inch wide, under which to pass into Scotland, and from Scotland again another narrow arch led to the Orkney Islands; these last, however, were dug in the perpendicular side of the hole. In the corners of these excavations tunnels ran deeper into the ground, and the ants immediately began hurrying their treasures, the eggs, down into these cellars. At one angle a tunnel went beneath the heath into further excavations beneath a second boulder stone. Without, a fern grew, and the dead dry stems of heather crossed each other. This discovery led to the turning over of another boulder stone not far off, and under it there appeared a much more extensive and complete series of galleries, bridges, cellars and tunnels. In these the whole life-history of the ant was exposed at a single glance, as if one had taken off the roofs of a city. One cell contained a dust-like deposit, another a collection resembling the dust, but now elongated and a little greenish; a third treasury, much larger, was piled up with yellowish grains about the size of wheat, each with a black dot on the top, and looking like minute hop-pockets. Besides these, there was a pure white substance in a corridor, which the irritated ants seemed particularly anxious to remove out of sight, and quickly carried away. Among the ants rushing about there were several with wings; one took flight; one was seized by a wingless ant and dragged down into a cellar, as if to prevent its taking wing. A helpless green fly was in the midst, and round the outside galleries there crept a creature like a spider, seeming to try to hide itself. If the nest had been formed under glass, it could not have been more open to view. The stone was carefully replaced.