As far as the eye could see the chasm extended, now growing in size, now contracting. A pale blue mist rose out of the opening, and the air was that of an August day no longer.
The sliding motion continued, and the chasm increased its width.
"Will it never stop?" asked Sam, almost thrown to the ground by a quick convulsion of the surface.
"Not just yet!" replied the Doctor gravely. "I can tell you in a moment just what has taken place. The weight of soil and timber on top of the dead glacier is shifting. The volcanic action tipped the moraine to the south and it broke, opening the way to the ice below. There is no knowing how serious the break may be. For all we know, the upheaval may send this whole moraine into the Gulf of Alaska."
"That's a cheerful proposition, too!" Tommy exclaimed.
"I wish I could get close enough to the chasm to look down," Sam observed. "I'll bet it's a thousand feet!"
"You'd better not try that!" advised Frank.
"The question before the house at the present moment," the doctor said, "is how I am going to get to my patient."
"Can't we get across this little crack in the earth?" asked Sam.
"That depends on the length of it!" answered Frank. "If the Doctor's theory is correct, this whole point has cracked away from the glacier above. In that case, we may be obliged to in some way work ourselves to the bottom of the chasm and up on the other side."