The evening sky was beginning to be overcast with clouds, and there was a moaning and sighing to the wind, as if it bemoaned the fact that the pleasant scene was so soon to be spoiled by a storm. "Better look to our tent-ropes, boys," suggested Gabe, for he and the two lads from the farm bunked together in a small tent that had been brought along. "I don't want it blown away in the night, and have us all get soaking wet." The darkness increased more rapidly, now that the sky was becoming thickly covered with clouds, and the wind grew stronger. "Say, do you notice anything queer?" asked Jed of Will, as they stood together on a little jutting point of rock and looked over the valley spread out below them, a valley now shrouded in gloom. "Something queer? How do you mean?" "I mean like when your foot goes to sleep, and you try to walk on it." "As if pins and needles were all over you?" asked Will. "Yes, that's it." "I did notice something like that," admitted his brother, "but I didn't think it was anything. It's growing worse, though." "You're right, it is. Let's ask the men and old Gabe if they feel it. Why, it's just like an electric battery now." The boys looked at each other curiously and in some alarm. They were both now conscious of a very peculiar sensation. Their flesh all over was tingling as if tiny needles were being brushed against them. "Do you notice anything queer, Gabe?" asked Will. "Queer!" exclaimed the miner. "I should say I did. It feels like ginger ale tastes." "That's it," remarked one of the men. "I was wondering what was the matter with me." The miners and the boys were ill at ease. There seemed to be something strange in the air about them--some unseen influence at work. They looked all around. The storm was evidently coming closer. The wind was now blowing quite a gale, and there were occasional mutterings of thunder. "The horses feel it, too," observed Ted. "I don't like it here. I wish we'd kept on, or else stopped down below." Hardly had he spoken than there came a vivid flash of lightning, followed an instant later by a startling clap of thunder. But it was not the lightning which caused every one in the camp to jump sharply. Nor was it the thunder. "Did you feel that?" cried Jed. "I should say I did," answered Will. "A regular electric shock, that's what it was. Felt as if I had hold of the business-end of a battery." There came another flash of lightning, a far-off one, for the forked tongues of it shot down behind a distant, towering peak, but the effect on the little party of gold-seekers was even more pronounced than before. Gabe fairly leaped into the air, in spite of his injured leg. "Tarantulas and centipedes!" he cried. "Something's the matter!" "We're on top of a natural electric battery!" shouted Ted Jordan. "No, we're not, but it's almost as bad," spoke one of the men. "I know what it is." "What then?" cried several.