Mercer constantly was evolving plans of the utmost daring, most of them indeed amounting practically to suicide for those undertaking them. But I held him back. Our present tactics were dangerous enough, although after the first few fatalities we succeeded in protecting our men, even though our projectors were invariably destroyed. One of Mercer's plans we tried with some success. There were some places in the light-barrage that were much less high than others. We devised a smaller rocket that could be fired from the platforms. Mercer took it up some twenty thousand feet, and sent several rockets over the light, which we hoped dropped into the city. A month went by in this way. We were in constant communication by water with the Great City, receiving supplies and reënforcements of men and armament. And then gradually the situation changed. Over a period of several days our hand-to-hand encounters with the enemy grew less frequent. Finally two or three days went by without one of them taking place. We became bolder and prepared to establish several projectors at different points for simultaneous fire at a given signal. The light-barrage in the valley remained unchanged, although now its beams held steady instead of sometimes swinging to and fro. We dislodged one of its projectors with a rocket, making a hole in the barrage, which this time was not repaired. And then, to our amazement, the lights one by one began to die away. We ceased operations, waiting. Within half a day they had all vanished, like lights which had flickered and burned out. Mercer, unthinking, was all for an instant attack. We could indeed have swept the valley now without difficulty; but there were thousands of people in the city--non-combatants, women and children--and to murder them to no purpose was not the sort of warfare we cared to make. It seemed probable that Tao had evacuated his position. The valley beyond the city led up into the mountains toward the Dark City, almost on the borderland of the frozen wastes of the Dark Country. Tao had protected this valley from behind so that we had been unable to penetrate it without making a detour of over twenty miles. This I had not done, although had the siege lasted longer I think with our next reënforcement we should have attempted it. With the extinguishing of the lights our long-range activities ceased. We anticipated some trick, and for several days remained quiet. Our girls could have flown over the city; but this I would not allow, fearing that a ray would bring them suddenly down. Miela and myself, occupying one of the stone houses down by the river, held a consultation there with Mercer and Anina. Mercer, as usual, was for instant action. "We might as well march right in," he declared. "They're out of business, or they've gone--one or the other." "To the Dark City they have gone, I think," Anina said. "I think so, too," Mercer agreed.