Man began a rapid decline, for the machines did all his work. With the construction of a machine that could originate a problem, man made a mistake. He had created a machine that was more powerful than he, except that it was immobile. And this machine originated a new machine, a machine that would release the energy of matter! It had developed this because it had been able to see that such energy existed. Man's machines could have solved it long ago, but the problem had never been stated. Now came a machine that could state its own problems--and solve them. And with this new energy it designed a new brain-machine. A brain machine such as no man's brain could conceive--a machine that could move! For it was powered by the energy of matter, and could move as no other machine had ever moved before--out into space! Still the machines worked for the Sirian man, and he learned of the new discovery, and began to design a new brain-machine. Some of the Sirians realized the danger that was facing them, and they had continued long researches on man's brain, and at last had discovered the secret of giving a machine that emotion we call devotion, loyalty, or gratitude. And they built a great machine on that principle and used material energy to power it. It was a success. It could think original thoughts. It pointed out the danger of the existing machines--they were stronger than man. It was only man's mobility and ability to control all mobile machines that had made him superior, for a brain without a tool, or body is helpless. And now that was lost. The existing brain-machines should be destroyed, and new ones built, using the principles that it was designed on. But the mischief was done. The new brain-machine, designed by a machine, had done it. A machine had been built that was controlled by thoughts, a machine that could be controlled by the machines. Each of these machines was given a small brain, equipped with televisor sight and hearing, and it was powered by material energy. They could run for years without outside care, for the thinking machinery they had was sufficient to keep them oiled, and to make them seek repairs when they were damaged. They were susceptible to thought forces, and did as the thought waves suggested and reported to the control brain exactly what was going on about it. And now this new brain developed a space-flyer to carry these machines, and man could not help knowing, for its every thought was recorded, for man's use. Then one day this record was found destroyed. The next day the brain-machine had left the planet, and taken with it the new space-flyer and the new telepathically controlled machines.