The parasites to which the veterinary alluded had always tasted to Cabot exactly like earth-born lobsters. The description of these new beasts were further suggestive of lobsters. He asked Emsul for a more detailed description, and found that this tallied still further with the earthly prototype. This reminded Myles of an interesting experiment which he had seen tried in the Harvard zoological laboratory, and which he now hoped to put to a practical use. So he asked: “Have these creatures a gravitational sense organ?” “Yes,” the Cupian veterinary replied, “although it is unlike ours. We Cupians, and I suppose you Minorians, have inside the skull on each side of the head, a group of three tubes like the spirit levels of a carpenter. “The corresponding organ of the scissor-clawed beast is different, although serving the same end. On each side of the thorax of these creatures there is a spherical cavity, with a small opening to the outside. This opening is just large enough to admit a grain of sand at a time. “The membrane which lines the cavity, exudes a liquid cement which unites into a little ball the grains of sand which enter. The cavity is lined with nerve ends; and, as the ball always rolls to the bottom side of the cavity, the beast is able to tell which direction is up, and which is down.” Cabot clapped his hands in glee. This was exactly as in the case of earth-born lobsters. “They won’t know which is up and which is down when I get through with them,” he exclaimed cryptically. It was quickly arranged that Nan-nan should go at once to the village near the lobster pool, and engage a gang of Cupian men to cut a swath through the thick woods which hem in the pool. When this was completed, he was to send a messenger to Luno Castle to summon Cabot, who, meanwhile, would be engaged in preparing certain mysterious electrical apparatus. For the present, the earth-man’s return was a secret. The plan worked to perfection. Only one day was consumed in chopping the path through the woods. On the second day after his meeting with Nan-nan and Emsul, Myles proceeded to the lobster pool by the kerkool, with his electrical equipment and several boats. XXIV THE LOBSTEROID CIRCUIT Myles could not help comparing his present ease of passage down the swath cut by the Cupians with his difficult grubbing through the shrubs a few feet an hour, or even with forcing his way behind the wedge-faced insect. Upon his arrival at the brink of the abyss, his first act was to test the black sand with an electric coil. As he had expected, it was magnetite, the only iron ore which will respond to a magnet. It was the same ore as he had used in his crucibles while making his radio set in Vairkingi.