Tom's plan was voted good so they hurried out of the temple, their feet echoing and re-echoing over the stone floor. The place, ruined and desolate as it was, had no terrors for them now. In fact they were glad of the very loneliness, and Tom and Ned actually looked about apprehensively as they emerged, fearing they might see a sign of the Mexicans or the Fogers.
"Guess they can't pick up our trail," said Tom, when, he saw of what Ned was thinking.
"No, we've got the place to ourselves. I wonder how long it will take for the air to get fresh?"
"Not so very long, I guess. There was a good draught. There must be some opening in the underground city by which the air is sucked in. They'd never have only one opening to it. But we don't need to look for the other. Come on, we'll get out the torches."
These electrical contrivances are familiar to all boys. A small electric lamp is set in the end of a hollow tube of tin, and about the lamp is a reflector. Dry electrical batteries are put in the tin tube, and by means of a push button the circuit is closed, illuminating the lamp, which gives a brilliant glow. Tom had a special kind of lamp, with tungsten filaments, which gave a very powerful light, and with batteries designed to last a long time. A clip on the spring controlling the push button made it so that the lamp could be made to give a steady glow. Thus they were well prepared for exploring the tunnel.
It took some little time to get the flash lamps ready, and when they were all charged and they had eaten, they went back to the opening to see if the air had cleared. Tom tested it by dropping a match down, and, to his delight it burned with a clear flame.
"It's all right!" he exclaimed. "The air is pure. Now to see where we will bring up. Come on, everybody."
"Jest one minute, Massa Tom," begged Eradicate, as the young inventor was about to descend the steps, which even the brightness of his lamp did not disclose the end. "Is yo' gwine down dar, Massa Tom?"
"Certainly, Rad."
"An' is yo'--'scuse me--but is yo' expectin' me fo' t' follow yo'?"