For another six hours they traveled downward steadily, stopping only once to eat. The descent during this time was not unlike that down the side of the valley, although towards the last it began rapidly to grow less precipitous. They now found themselves confronted frequently with gentle slopes downward, half a mile or more in extent, and sometimes by almost level places, succeeded by another sharp descent. During this part of the trip they made more rapid progress than at any time since starting, the Very Young Man in his enthusiasm at times running forward and then sitting down to wait for the others to overtake him. The light overhead gradually faded into the characteristic luminous blackness the Chemist had described. As it did so, the phosphorescent quality of the rocks greatly increased, or at least became more noticeable, so that the light illuminating the landscape became hardly less in volume, although totally different in quality. The ground underfoot and the rocks themselves had been steadily changing. They had lost now almost entirely the yellowishness, metal look, and seemed to have more the quality of a gray opaque glass, or marble. They appeared rather smoother, too, than before, although the huge bowlders and loosely strewn rocks and pebbles still remained the characteristic feature of the landscape. The three men were still diminishing in size; in fact, at this time the last dose of the drug seemed to have attained its maximum power, for objects around them appeared to be growing larger at a dizzying rate. They were getting used to this effect, however, to a great extent, and were no longer confused by the change as they had been before. It was the Big Business Man who first showed signs of weakening, and at the end of six hours or more of steady--and, towards the end, extremely rapid--traveling he finally threw himself down and declared he could go no farther. At this point they rested again several hours, taking turns at watch, and each of them getting some measure of sleep. Of the three, the Very Young Man appeared in the best condition, although possibly it was his enthusiasm that kept him from admitting even to himself any serious physical distress. It was perhaps ten or twelve hours after they had taken the six pills that they were again ready to start downward. Before starting the three adventurers discussed earnestly the advisability of taking the other six pills. The action of the drug had ceased some time before. They decided not to, since apparently there was no difficulty facing them at this part of the journey, and decreasing their stature would only immeasurably lengthen the distance they had to go.