Twenty of the hundred cars which were gradually taking shape he set apart, however, after they were tested--and these he had equipped with all-metal wheels carrying cross-bars on their tires like short, strong teeth. He put workmen to the task of making metal walls to bolt upon each chassis. And these walls were pierced with slots. Thus he arranged for twenty armored cars and had them set aside. Likewise he speeded the construction of numbers of flat-bottomed power-boats capable of speed, yet having floor space enough to transport no small number of men. A month passed, two months, three. Always the fires in Ladhra and Himyra flared. Men toiled day and night. Croft's plans were drawn for each part of the arm he intended to make. Machines were assembled and set up--motors were harnessed to them to Robur's amazement. Croft found the Tamarizians apt of comprehension and willing to work. Each man employed was sworn to fealty to the State. Each knew himself a member in an army working for the safety of the nation. At the end of three months he found himself the supreme captain of a picked corps. And at the end of a month he was ready to begin the actual making of arms. Now and then Croft went back to his earthly body, not only to renew its physical life, but to gain help in the work he was carrying on by learning fresh details on each trip. He gave up any intention of manufacturing machine guns, as a thing requiring too much time. On an average he spent two days of every week on earth. His sleeps on Palos had become too frequent to cause any further comment when they occurred. Thus a fourth month passed. In it Croft accomplished several things. He did not stop motor production with the first hundred. He continued their building and began selling the output of the shops to private owners. The things became a not too unusual sight on the Himyra streets, and the first motor caravan was organized and crossed the inland desert to Milidhur with success. One special car Croft had built. On it he lavished all his present ability of refinement. And when it was done he drove it to Lakkon's mountain mansion in the twilight of a busy day. It was for Naia, and himself he gave it to her, and after the evening meal when the three moons rose he placed her in it and taught her how to drive. Far down the mountain road and out upon the desert between the foot of the hills and Himyra they went. They were alone in the soft light which turned the dun plain to silver. Far off the red fires in Croft's workshops flared over Himyra's walls. Croft stopped the car and pointed to that red reflection in the lesser light. Suddenly it seemed to him that in all the world there were just they two--that they were alone--that nothing else mattered. His heart swelled.