I closely watched Mr. Edison's expression in order to see how this most alarming news would affect him. Although he fully comprehended its fearful significance, he did not lose his self-command. "Well, well," he said, "then it will become necessary for us to act quickly. Evidently we cannot wait for the smoke to clear off, even if there was any hope of its clearing. We must get down on Mars now, having conquered it first if possible, but anyway we must get down there, in order to avoid starvation." "It is very lucky," he continued, "that we have ten days' supply left. A great deal can be done in ten days." A few hours after this the commander called me aside, and said: "I have thought it all out. I am going to reconstruct some of our disintegrators, so as to increase their range and their power. Then I am going to have some of the astronomers of the expedition locate for me the most vulnerable points upon the planet, where the population is densest and a hard blow would have the most effect, and I am going to pound away at them, through the smoke, and see whether we cannot draw them out of their shell." With his expert assistants Mr. Edison set to work at once to transform a number of the disintegrators into still more formidable engines of the same description. One of these new weapons having been distributed to each of the members of the squadron, the next problem was to decide where to strike. When we first examined the surface of the planet it will be remembered that we had regarded the Lake of the Sun and its environs as being the very focus of the planet. While it might also be a strong point of defence, yet an effective blow struck there would go to the enemy's heart and be more likely to bring the Martians promptly to terms than anything else. The first thing, then, was to locate the Lake of the Sun on the smoke hidden surface of the planet beneath us. This was a problem that the astronomers could readily solve. Fortunately, in the flagship itself there was one of the star-gazing gentlemen who had made a specialty of the study of Mars. That planet, as I have already explained, was now in opposition to the earth. The astronomer had records in his pocket which enabled him, by a brief calculation, to say just when the Lakes of the Sun would be on the meridian of Mars as seen from the earth. Our chronometers still kept terrestrial time; we knew the exact number of days and hours that had elapsed since we had departed, and so it was possible by placing ourselves in a line between the earth and Mars to be practically in the situation of an astronomer in his observatory at home. Then it was only necessary to wait for the hour when the Lake of the Sun would be upon the meridian of Mars in order to be certain what was the true direction of the latter from the flagship. Having thus located the heart of our foe behind its shield of darkness, we prepared to strike.