“You have the advantage of us,” he said. “Therefore, my armies will retire at once; but I warn you that you shall be conquered in the end and be made to suffer for this.” “Very well, your Highness. I suggest that you give orders immediately for their retirement as, unless it is commenced within a few minutes. I shall resume their destruction.” Again the generalissimo was obliged to restrain the emperor’s burst of passion. A moment later, at a curt nod of assent, from the emperor, the generalissimo dispatched the officer with a command to begin an immediate general retirement of all forces. * * * * * The first contingent was soon moving northward. The emperor and generalissimo had departed ominously for their headquarters. The _Sphere_ continued to drift idly, settling ever closer to the ground. The enemy forces still stretched more than a mile between the _Sphere_ and the city. How Robert and Taggert yearned for a stiffening of the breeze that they might be swept safely beyond the enemy’s lines before the descending _Sphere_ placed them in their power! Even now soldiers below paused in their preparations for retreat to gaze up at them curiously, albeit anxiously, evidently wondering why the _Sphere_ hovered so low. Should the true reason be guessed, their temporary victory would be lost. The next ten minutes seemed like an eternity to Robert. It had brought them only a little nearer the city and their friends, while scarcely thirty feet separated them from the enemy. Some of the troops were already marching off toward the south beneath them, but it was a physical impossibility for the thousands still between the _Sphere_ and its goal to move out of the way in less than half an hour. And half an hour spelled almost certain disaster for the _Sphere_. “Looks as if we’ll have to indulge in a little more diplomacy,” Robert remarked. “Drop in upon his Royal Highness to bid him goo’bye, so to speak,” said Taggert. “Something like that.” At this moment the suspense was broken by a sudden lurch of the _Sphere_. The gyrostats had stopped! With but the disk’s diminished power to break its fall, the _Sphere_ dropped into the sand with a jarring thud. The Martians had carefully avoided the section beneath the _Sphere_. Consequently it fell clear. For several minutes they kept their distance. It was evident that they all feared this mysterious machine greatly. Presently a pompous officer strode into the space about the _Sphere_. Clearly he saw in the situation great possibilities for his own future and he intended making the most of it. Yet, like the rest, he was not certain that the _Sphere_ was as helpless as it seemed. Before he had given an order. Robert stepped out of the _Sphere_. Robert interrupted the officer as he was about to speak. “I come to give warning that unless the retirement of all the emperor’s forces is accomplished more rapidly, I will resume their destruction,” he said, imperiously.