THE EARTHWORM SYSTEM AT PANAMA
A principle similar to his swallowing operations is frequently employed in engineering; as in making the Panama Canal, where dredging machinery dug out swamps and pumped the mud through a tube into other swamps to fill them up and help get rid of the mosquitoes.
In pushing the earth away the worm uses the principle of the wedge, stretching out his "nose"—as you have often seen him do when crawling—and poking it into the crevices in the ground; much as the wheat roots poke their little noses through the fertile soil the earthworm makes.
And, as in human engineering and the work of the ant, the earthworm doesn't throw the dirt around carelessly. He casts it out, first on one side and then on the other; using his tail to spread it about neatly.
THE TILING IN THE EARTHWORM'S HOUSE
The walls of the earthworm's house are plastered, too. At first they are made a little larger than his body. Then he coats them with earth, ground very fine, like the clay for making our cups and saucers, and for making the beautiful white tiling on the walls at the stations of a city subway. When this earthworm "porcelain" dries it forms a lining, hard and smooth, which keeps the earthworm's tender body from being scratched as he moves up and down his long hallway. It also enables him to travel faster because it is smooth, and it strengthens the walls.
The burrows which run far down into the ground, as all finally do toward Autumn, end in a little chamber. Into this tiny bedroom the worm retires during the hot, dry days of August and there he spends the Winter—usually with several companions, all sound asleep, packed together for warmth.
AND RUGS ON THE FLOORS!
Sometimes the Summer and Winter residences are quite ambitious, several burrows opening into one large chamber and each tunnel having two, sometimes three, chambers of its own—like a fashionable apartment with its main reception-room, and still more like the central sitting-rooms in Greek and Roman palaces. And the earthworm seems even to have some idea of mosaics, for it is the general practice to pave these chambers with little pebbles about the size of a mustard-seed. This is to help keep the worm's body from the cold ground. In addition to the mosaic floors the earthworms have rugs with lovely leaf patterns like the Oriental rugs that are so highly prized; and, as in the case of genuine Oriental rugs, no two patterns are alike. These rugs are leaves which the earthworm drags into his burrow, not for food but for house furnishing. When used for house furnishing they are placed in the entrance-hall; that is to say, they are used to coat the mouth of the burrow to prevent the worm's body from coming in contact with the ground. The mouth of the burrow, of course, is just where it is coldest at night in the Summer, the time of year when the earthworm spends a great deal of his time in the front of his house. The surface of the earth, you know, cools very rapidly after sunset and the dew on the grass in the morning is so cold it makes your bare feet ache. The worm requires damp earth around him because he breathes through his skin and must keep it moist, but at the same time he is sensitive to cold.
And to drafts. Ugh!