* * * * * Strykalski opened his eyes and stretched his battered body. His head was bandaged, and he could feel the familiar tingle of paratannic salve on his burns. Pain still throbbed in little red needles behind his dazzled eyes. He drew a long rasping breath and looked around him. He was in the _Cleopatra's_ infirmary. A Medic was standing near the bulkhead. Cob lay on a bunk nearby. Ivy and Celia Graham were leaning over him. "Great Space!" he muttered, "What happened?" "The shot Cob fired ... it ... it blew up," Celia said. "That's putting it rather mildly. But why? And how did we get back here?" "Celia found you on the Radar," said Ivy, "And Bayne took a skeeterboat out and picked you up after we got Lover-Girl back right side up." "Cob?" As though in answer to Strykalski's question, a low moan came from the bandaged form of the Executive. "Ohhh.... Ye gods and ... little catfish! I wish I ... had a Martini...." Strike smiled through cut lips. Cob was all right. He looked up at Ivy again. "But what happened?" "Listen!" Ivy was saying excitedly, "I've got it! The answer! All the answers, I think! The glowing of the ship ... the lack of mass for everything native to this space ... the solid shot exploding!" Things were becoming clear to Strykalski now. Of course! He sat up painfully. It was really simple enough when one thought it through. In negative space.... Ivy went on. "Strike, the ship glows because there is matter everywhere ... even in interstellar space. Not much, but enough to bombard the hull with tiny particles. The radiation the Geigs picked up is caused by atomic _disintegration_! We've had fission and fusion for two hundred years now ... but this is the complete transmutation of matter to energy! The complete utilization of atomic energy! And the thing that causes it is the reaction between our kind of matter and...." "_Contraterrene matter!_" he exclaimed. "That's it, isn't it Ivy?" The girl nodded. "The charges of the atomic components are reversed in this space! You would have made yourself into a ... a _bomb_ if you had touched that planetoid out there!" Her face paled. "Oh, Strike! You almost killed yourself!" Thoughts were boiling around in Strykalski's head now. An idea ... a crazy, audacious idea was taking shape. He swung his legs over the side of the bunk. "Listen, Ivy ... in this space, _we_ are the unnatural form of matter, and here we are sort of walking bombs. Right?" She nodded, puzzled. "Well, what if we should transport some contraterrene matter back into prime-space ... a planetoid for example ... what then?" The girl's face showed comprehension. "It would be the most devastating bomb ever dreamed of. It would release every erg in its component atoms the minute it came into contact with anything terrene!" She stopped short, her eyes wide. "Strike!" "Would it work, Ivy?" he pursued. "Yes!" she gasped, "Yes, I think it would!" "Can we do it?"