And on all the worlds great works were to be done. The records of a civilization ten thousand thousand thousand years old must be collected and prepared for their journey across the void. The exhibits from museums, ages old, must be packed with tenderest care. They had strange exhibits there of the first beginnings of civilization, tools and weapons of savage man, strange things that killed or injured by throwing small bits of metallic matter at the enemy. Strange clumsy vehicles they had, made of metals that corroded so rapidly as to fall to pieces in a brief 1,000 years or so, unless they were preserved in an atmosphere of argon and driven by great clumsy engines tapping the slight energy of molecules with an efficiency of hardly 10 per cent. Other machines that had been intended to drag man through the air, not supported by forces, but held up by air! Then came the first ancient antigravitors; then the swifter machines propelled by the energy of matter. Exhibits unutterably ancient they had, and these must be sent across all that void. Invaluable archives they were. But with them must go their own great machines, mighty mechanisms for producing their foods, for making their ships; the thousand and one things that went to make up the great structure of their age-old civilization. And huge sending stations of inconceivable power had to be erected to transmit them. Titanic projectors capable of sending a machine weighing a quarter of a million tons in one scanning. Other machines were so huge that they must be cut into sections and sent in pieces. * * * * * A greater work--a quieter, invisible work--was being done by tireless workers in the laboratories. Fifty-three hours a day they worked in the great government laboratories on Earth. On Venus the shorter day made shorter hours desirable. But steadily the scientists were working on their problem. At last the Minus Energy was developed. They were to try it out before equipping the entire fleet with it. At last ten ships were equipped and sent with a scanner machine to Betelguese. Now they courted an encounter with the Force Giants. They were soon satisfied, for thousands of them came at terrific speed the moment they attacked one. That first one had floated into range as they threw a searchlight on it; then, as it began to color with the deadly violet and red destruction, a tiny projectile was launched at it. Not more than six inches long by two in diameter it raced at its target at nearly a thousand miles a second. It was carefully followed by the anxious watchers at the ship's electroscopes--it reached the floating Thing, and exploded.