Janus and the others directed work at the forges and metal shops. Everyone, men and women alike, who could be spared from the border defenses, were given assignments. Mari was a surprise to the new men. Already she knew the ancient science textbooks by heart, and she thirsted for more knowledge. She was everywhere, directing, helping, learning. She grasped the principle almost at once when Brownell explained: "Briefly, the atom itself must not be shattered. That has been your mistake. Successive sheathes of electrons must be stripped without disruption of the ultimate atomic structure. That means swift transmutations, not disintegration. Most important of all, the electrons must be propelled along a controlled, directional beam." Only Ferris was dissatisfied at the hard work. In their quarters, at the end of the first week, he complained: "What's all this getting us? I thought we came out here to make a fortune! That's the story you gave me, Janus, when you rooked me into this deal." Janus looked at him distastefully. "Haven't you ever wanted to do a decent act in your life? Lord knows I've done some scandalous things, but these people need our help now and they deserve it!" "That's not getting back the fortune I sunk into this venture," Ferris grumbled. "We'll think of that later." The work was slower than they wished, for it became apparent the Perlac attack was going to materialize any day, any hour. As leader of the defense, the all-out call was left to Donli, who, with his select group, remained at the border constantly now. And on the tenth day, even before the new pistols had been assembled or tested--the call came. One of the scouts raced into the city with the signal. * * * * * Everyone, men and women alike, left their work instantly. Dozens of the electrically-motored surface cars were waiting, and soon they were racing along the road. Within the hour they had reached the twilight zone to reinforce Donli's group. Each person was equipped with an electric rifle which, at the longer distances, stunned but was not fatal. And there were quantities of atomic grenades. The new Earthmen retained their atomic rifles and neutro-pistols, as they better understood the operation of these weapons and could use them to more advantage. The attack had not yet come but Donli was expecting it at any minute. Each group took up its assigned position behind a barrier. Mark found himself beside Janus and was glad, for he liked that blustering, red-bearded giant. "It's going to be hell," Janus promised, peering into the twilight gloom. "We have to wait for them. The Perlacs can come over into our lighter gravity, but their gravity'd be fatal to us!" Mark nodded. "It means we'll be fighting a strictly defensive battle."