“Never; it would be over fifty miles in utter darkness. There may be a thousand trestles and bridges over frightful chasms: for the most part, I have heard the tunnel is a natural channel or a succession of caverns united by tunnels. The other is the safer way, though it certainly is risky enough.” Louder and nearer grew the rumbling noise, and a faint light began to shine from the tunnel and flash on the cliff opposite. “It is the sun's headlight,” explained Branasko. Johnston was thrilled to the centre of his being as he saw the light playing over the polished tracks and cables and illuminating the walls of the great tunnel. Suddenly there was a deep, mellow-toned stroke of a bell in the sun, and, as the two men shrank involuntarily into the deeper shade of the cliff, the great globe, a stupendous ball of crystal, five hundred feet in height, slowly emerged from the mouth of the tunnel and came to a stop under the opening in the rock which led to the space above. “What had we better do now?” said Johnston. “Wait,” cautioned Branasko, and he drew the American to a great boulder nearer the sun, from behind which they could, without being seen, watch the action of the crowd of workmen that was hurriedly approaching. They placed ladders of steel against the sides of the sun and swarmed over it like bees. “They are cleaning the glass and adjusting the lights,” said the Alphian; “wait till they go round to the other side. Don't you see that square opening near the ground?” The American nodded. “It is the door,” said Branasko, “and we must try to enter it while they are on the other side. Let us slip nearer; there is another rock ahead that we can hide behind.” Suiting the action to the word, Branasko led the way, stooping near to the ground until both were safely ensconced behind the boulder in question. They were now so near that they could hear the electricians rubbing the glass. One who seemed to be superintending the work opened the door and went into the sun and lighted a bright light. From where they were crouched Johnston and Branasko caught a view of a little hall, a flight of stairs, and some pictures on the walls. Presently the man extinguished the light and came out. “They are removing their ladders from this side,” said Branasko in a whisper. “Be ready; we must act quickly and without a particle of sound. Run straight for that door and climb up the steps immediately.” The men had all gone round to the other side, and no one was in sight.