From the entrance of this cavern to the bottom of it was a steep descent of about twelve miles. Ropes and stairways had been provided in the difficult parts, but it still remained a toilsome task to go to the surface and back again. Women and children generally remained down about one hundred to one hundred and thirty days, according to the length and severity of the winter. A deep, clear stream in the bottom of the cave supplied water. Great care was taken so that the water should not become polluted. The supply of air was perfect.
Scarcely had the community got settled when they began to notice that their water was turbid at times, that it was sometimes warmer than common, and that some days there was no water to be had except what could be caught from the roof of some caverns that were too damp to be habitable. It was soon decided by those in authority to follow the water by boring, and the requisite machinery was quickly got to work.
The floor of the cave is five miles in vertical depth from the surface, so the people thought they could not have to go far before getting to water. In this they were disappointed. The bore was tubed for nearly two miles, and it was finally decided to work one more day and give up. How little the workers thought that the destiny of a world hung upon that decision. What would our race life have been by this time if those men had not decided to work one day more?
Barely had the machine begun to work on the morning of this last day when the great cave became a blaze of light brighter far than the day on the surface above the cave. What had happened? A crowd of people rushed towards the light from all sides. They met several coming from it; some of these were carrying wounded men. Close by the light were two objects that could only be viewed with a shudder. They were a pair of blackened cinders shrivelled up into half their original size. The electric fire that had leaped up the rod and tubes of the bore had rushed through these two bodies, and not only killed but cremated them before they had time to fall to the ground.
What about the water? There was none where that fire came from, but by some strange connexion of the two events, or perhaps by some coincidence, the stream began to flow again, and the lake filled up to its old level.
Two men were killed, one died next day, the rest recovered. The people in the cave had water in abundance, and a great light that changed its colors now and then but never diminished. And now the questions arose, what is the light? Whence comes it? Is it likely to be permanent?
A great electrician was sent for, and with him came a geologist and some other specialists. After a series of experiments they came to the conclusion that the outer flow of electricity, that which goes back to the southern electric pole, following lines not far below the surface of the planet, had been tapped, and that the light was electric. The flow from that source