The landing-compartment about us held scores of resting cylinders like our own, and even as we looked about we saw throngs of Neptunians hastening forward and removing from our own and the other ten that had just landed, the disassembled mechanisms which they had brought from Neptune. The leader, however, motioned to our guards to follow with us, and set off quickly across the landing-compartment toward one of its doors. Following him, our four tube-armed guards watchful now about us, we saw him pass through the low, broad door before us, and though his strange disk-body passed easily through that door, Marlin and I were forced to stoop low to get through it. Then, our guards never relaxing their cautious watch over us, we were moving on through the next compartment, and the next, and the next, on through compartment after compartment, all thronging with Neptunians, moving across the great compartment-city toward the twilight band that divided Triton's dark and sunlit sides. And as Marlin and I moved with our guards and their leader thus through the pale daylight of Triton, through the compartments crowded with masses upon masses of Neptunians, we forgot almost the uncertain fate that hung over us, in the interest and wonder of what we saw. For though we had explored the greater compartment-city that covered all the surface of mighty Neptune, had seen its marvels also, it had been a city dead, a city of lifeless and unused mechanisms whose purposes we had not been able to guess. But here on Triton, in the compartments that covered its surface, we saw a Neptunian city bursting with crowding life, saw it as the giant city of Neptune itself must once have been, before some unguessed purpose of the Neptunians had brought them here to Triton. And, seeing it thus, we were able to comprehend many things that had puzzled us in our venture through the city on Neptune's lifeless surface. * * * * * We passed through compartments in which throngs of Neptunians moved about great rows of looming, pear-shaped mechanisms such as we had seen on Neptune, great water-making mechanisms that were beating here with a slow, rhythmic sound of power, and from which there pulsed into the great connecting pipes a ceaseless gush of water. That water, we knew, was made synthetically in the mechanisms by the combination of hydrogen and oxygen atoms, but whether those atoms were derived, as on Neptune, from the break-down of Neptune's great vapor-masses, or whether they were formed themselves from the primal electricity, we could not guess. Through many compartments of these we passed, and through other compartments that held great pumps that evidently forced the water supplies thus manufactured to every part of Triton's surface.