Imagine, if you can, what would happen if some fifty thousand metric tons of material from the innermost core of Sirius B were to be taken to Grand Base, separated into twenty-five packages, each package placed at a strategic point, and all restraint instantaneously removed. What would have happened then, was what actually _was_ happening! As has been said, for moments nothing moved except the ever-expanding spheres of destruction. Nothing _could_ move--the inertia of matter itself held it in place until it was too late--everything close to those centers of action simply flared into turgid incandescence and added its contribution to the already hellish whole. As the spheres expanded, their temperatures and pressures decreased and the action became somewhat less violent. Matter no longer simply disappeared. Instead, plates and girders, even gigantic structural members, bent, buckled, and crumbled. Walls blew outward and upward. Huge chunks of metal and of masonry, many with fused and dripping edges, began to fly in all directions. And not only, or principally, upward was directed the force of those inconceivable explosions. Downward the effect was, if possible, even more catastrophic, since conditions there approximated closely the oft-argued meeting between the irresistible force and the immovable object. The planet was to all intents and purposes immovable, the duodec to the same degree irresistible. The result was that the entire planet was momentarily blown apart. A vast chasm was blasted deep into its interior, and, gravity temporarily overcome, stupendous cracks and fissures began to yawn. Then, as the pressure decreased, the core-stuff of the planet became molten and began to wreak its volcanic havoc. Gravity, once more master of the situation, took hold. The cracks and chasms closed, extruding uncounted cubic miles of fiery lava and metal. The entire world shivered and shuddered in a Gargantuan cosmic ague. * * * * * The explosion blew itself out. The hot gases and vapors cooled. The steam condensed. The volcanic dust disappeared. There lay the planet; but changed--hideously and awfully changed. Where Grand Base had been there remained nothing whatever to indicate that anything wrought by man had ever been there. Mountains were leveled, valleys were filled. Continents and oceans had shifted, and were still shifting; visibly. Earthquakes, volcanoes, and other seismic disturbances, instead of decreasing, were increasing in violence, minute by minute. Helmuth's planet was, and would for years remain, a barren and uninhabitable world. "Well!" Haynes, who had been holding his breath unconsciously, released it in an almost explosive sigh. "That is inescapably and incontrovertibly _that_. I was going to use that base, but it looks as though we'll have to get along without it." Without comment Kinnison turned to the gamma-zeta observers. "Any traces?" he asked.