Godfrey, now quite alive to the past, gave an ejaculation of annoyance.
"I'm a pretty doctor not to have warned you against noxious vapours! It's a marvel we are both alive. But why was I not overpowered?"
"Probably because you were not holding your face to the earth where the gas collects, though very likely you, too, would have succumbed in a few moments. However, all's well that ends well. Your striking a light was a fortunate thing, for it appears to have acted like an electric discharge in instantly clearing the air. True, you were stunned, but I recovered; whether instantly by the explosion, or more slowly by the purifying atmosphere, I cannot tell. All I know is I awoke, and realizing what had happened, and feeling you beside me, I lost no time in dragging you out into the open air. And here we are, none the worse for our experience, I trust. No doubt it was occurrences like this that caused the old Norsemen to believe that Odin guarded the tombs of the dead by darting forth flames."
"The fires of the Asas are real enough, after all," muttered Godfrey, still feeling like one in a dream. "Hasn't the sound of the explosion brought any one here?"
"It seems not," said Idris, looking round. "So far we are safe. Old Orm offers a stubborn resistance," he continued. "'He being dead, yet fighteth.' But he is doomed to be defeated, for I will not go until I have examined the interior of the hillock."
"You are not thinking of venturing into that deathtrap again?" said Godfrey, aghast.
"There is no danger now: at least, not from gases. The explosion dissolved them, and the outer air has had time to penetrate within. Besides, forewarned is forearmed. We know our peril: if one of us should be overpowered, the other must drag him out."
"How can you make an investigation without a light?"