"Come!" barked one of the guards in Dick's ear.
Dick attempted no further resistance. Convinced of its futility, sick and reeling from the blows he had received, he accompanied his captors quietly. There was nothing more that he could do, either for President Hargreaves or for old Luke, but he still imagined the possibility of somehow warning the approaching fleet or the occupants of the dirigible.
He was led along the passage, past the guards, and up the stairs again. The top door opened upon vacancy; it closed, and vanished. Dick felt the rugs beneath his feet, but he was to all appearances standing on a square of bare earth in the middle of a prairie.
"Come!" barked the guard again, and Dick accompanied him, trailing his silver chain. Behind came Von Kettler.
"Here are steps!" said the guard, after they had proceeded a short distance.
Dick stumbled against the lowest step of an invisible flight. The breeze was cut off, showing that they had entered a building. Underneath was a large oval of bare ground. Dick found a handrail and groped his way up around a spiral staircase, four flights of it.
"Here is a room!"
ick saw that widening edge of door again. The room inside was perfectly visible, though it seemed to be supported upon air. It was a spheroid, of huge size, with a number of large windows set into the walls, and it was filled with machinery. About a dozen workmen in blue blouses were moving to and fro, attending to what appeared to be a number of enormous dynamos, but there were other apparatus of whose significance Dick was ignorant. The dynamos were whirring with intense velocity, but not the slightest sound was audible.