The rebuke had its effect, and with no further protest the company boarded the small cars, which shot through an opening in the wall and into a street of that strange subterranean city. Breckenridge, in the last car to leave the portal, studied his surroundings with interest as his conveyance darted through the gateway. More or less a fatalist by nature and an adventurer, of course, since no other type existed among the older spacehounds of the IPC, he was intensely interested in every new phase of their experience, and was no whit dismayed or frightened.

He found himself seated in a narrow canoe of metal, immediately behind the pilot, who sat at a small control panel in the bow. Propelled by electromagnetic fields above a single rail, upon lightly touching and noiseless wheels, the terrestrial pilot saw with keen appreciation the manner in which switch after switch ahead of them obeyed the impulses sent ahead from the speeding car. The streets were narrow and filled with monorails; pedestrians pursued their courses upon walks attached to the walls of the buildings, far above the level of the streets. The walls were themselves peculiar, rising as they did stark, unbroken, windowless expanses of metal, merging into and supporting a massive roof of the same silvery metal. Walls and roof alike reflected a soft, yet intense, white light. Soon a sliding switch ahead of them shot in and simultaneously an opening appeared in the blank metal wall of a building. Through the opening the street-car flew, and as the pilot slowed the canoe to a halt, the door slid smoothly shut behind them. Parking the car beside a row of its fellows, the Callistonian driver indicated that the Terrestrials were to follow him and led the way into a large hall. There the others from the Arcturus were assembled, facing Captain King, who was standing upon a table.

"Fellow travelers," King addressed them, "our course of action has been decided. There are two hundred three of us. There will be twenty sections of ten persons, each section being in charge of one of the officers of the Arcturus. Doctor Penfield, our surgeon, a man whose intelligence, fairness, and integrity are unquestioned, will be in supreme command. His power and authority will be absolute, limited only by the Callistonian Council. He will work in harmony with the engineer, who is to direct the entire project of building the new vessel. Each of you will be expected to do whatever he can—the work you will be asked to do will be well within your powers, and you will each have ample leisure for recreation, study, and amusement, of all of which you will find unsuspected stores in this underground community. You will each be registered and studied by physicians, surgeons, and psychologists; and each of you will have prescribed for him the exact diet that is necessary for his best development. You will find this diet somewhat monotonous, compared to our normal fare of natural products, since it is wholly synthetic; but that is one of the minor drawbacks that must be endured. Chief Pilot Breckenridge and I will not be with you. In some small and partial recompense for what they are doing for us all, he and I are going with Captain Czuv to Callisto, there to see whether or not we can aid them in any way in the fight against the hexans. One last word—Doctor Penfield's rulings will be the products of his own well-ordered mind after consultation and agreement with the Council of this city, and will be for the best good of all. I do not anticipate any refusal to cooperate with him. If, however, such refusal should occur, please remember that he is a despot with absolute power, and that anyone obstructing the program by refusing to follow his suggestions will spend the rest of his time here in confinement and will go back to Tellus in irons, if at all. In case Chief Pilot Breckenridge and I should not see you again, we bid you goodbye and wish you a safe voyage—but we expect to go back with you."

Brief farewells were said and captain and pilot accompanied Czuv to one of the little street-cars. Out of the building it dashed and down the crowded but noiseless thoroughfare to the portal. Signal lights flashed briefly there and they did not stop, but tore on through the portal and the tunnel, with increasing speed.

"Don't have to transfer to a big car, then?" asked Breckenridge.

"No," King made answer. "Small cars can travel these tubes as well as the large ones, and on much less power. In the city the wheels touch the rails lightly, not for support, but to make contacts through which traffic signals are sent and received. In the tunnels the wheels do not touch at all, as signaling is unnecessary—the tunnels being used infrequently and by but one vehicle at a time. No trolleys, tracks, or wires are visible, you notice. Everything is hidden from any possible visiray of the hexans."

"How about their power?"

"I don't understand it very well—hardly at all, in fact."

"It is quite simple." To the surprise of both Terrestrials, Czuv was speaking English, but with a strong and very peculiar accent; slighting all the vowels and accenting heavily the consonant sounds. "The car no longer requires my attention, so I am now free to converse. You are surprised at my knowing your language? You will speak mine after a few more applications of the thought exchanger. I am speaking with a vile accent, of course, but that is merely because my vocal organs are not accustomed to making vowel sounds. Our power is obtained by the combustion of gases in highly efficient turbines. It is transmitted and used as direct current, our generator and motors being so constructed that they can produce no etheric disturbances capable of penetrating the shielding walls of our city. The city was built close to deposits of coal, oil, and gas of sufficient amount to support our life for thousands of years; for from these deposits come power, food, clothing, and all the other necessities and luxuries of our lives. Strong fans draw air from various extinct craters, force it through ventilating ducts into every room and recess of the city, and exhaust it into the shaft of a quiescent volcano, in whose gaseous outflow any trace of our activities is, of course, imperceptible. For obvious reasons no rockets or combustion motors are used in the city proper."

Thus Captain Czuv explained to the Terrestrials his own mode of life, and received from them in turn full information concerning Earthly life, activity, and science. Long they talked, and it was almost time to slow down for the journey's end when the Callistonian brought the conversation back to their immediate concerns.