"You must be well aware of what the result of continued catastrophes of this sort will be. Already the wildest panic has gripped the section around Chicago, and the rest of the country. The whole world in fact is trembling upon the brink of a similar panic. The very uncertainty of these disasters encourages panic. None can say that the next blow will not be in his city and cut away his home and his life. All are aware now that your theory is correct, and that adds to the horror. For if a vessel or vessels with alien beings of some sort in it actually hover far above, none can say what greater horrors it may still loose upon us. We must strike back in some way, must drive these beings, whatever their nature, from the earth. Would there be any chance of doing so with dirigibles or planes, in your opinion?" "Not a chance, sir," Dr. Howard replied at once. "The rarity of the atmosphere at its surface makes even an attempt impossible, for no ship of ours could ever reach the surface of the atmosphere." "But what are we to do? Is there no method by which we can combat this menace? Must we lie supine and let whatever cataclysmic terror they choose descend on us?" All eyes were upon Dr. Howard as he gravely answered. "Since I first comprehended what lay behind these catastrophes I have sought for some method of halting them, some method of striking back at whatever ship or ships from space are hovering over us. To find such a method I have had recourse to the same analogy that has been made so terribly clear to us, the analogy between ourselves at the bottom of our air-ocean and the creatures at the sea's bottom. "Suppose those creatures far within the sea's depths had some intelligence and science, and suppose they wished to halt the trawling of our ships whose great scoops sweep down now and again upon them. How could they do so? They could not venture up to the ocean's surface. But one thing they could do, and that would be to send up something that would fight for them, that would make it impossible for the trawling ships to cruise longer on the surface! "They could, granted science and intelligence enough, construct great mines in vast numbers. These, if attached to air-filled globes, would be swept instantly up to the ocean's surface when released. They would float there indefinitely, and any ships cruising to and fro would sooner or later strike one and be destroyed, unless they were warned by the previous destruction of one. In this way the creatures of the sea's depths could prevent our cruising above and trawling for them.