Hatteras, however, climbed up the steepest ascents with surprising agility, disdaining the help of his staff.
He arrived before long at a circular rock, a sort of plateau about ten feet wide. A river of boiling lava surrounded it, except in one part, where it forked away to a higher rock, leaving a narrow passage, through which Hatteras fearlessly passed.
Here he stopped, and his companions managed to rejoin him. He seemed to be measuring with his eye the distance he had yet to get over. Horizontally, he was not more than two hundred yards from the top of the crater, but vertically he had nearly three times that distance to traverse.
The ascent had occupied three hours already. Hatteras showed no signs of fatigue, while the others were almost spent.
The summit of the volcano appeared inaccessible, and the Doctor determined at any price to prevent Hatteras from attempting to proceed. He tried gentle means first, but the captain's excitement was fast becoming delirium. During their ascent, symptoms of insanity had become more and more marked, and no one could be surprised who knew anything of his previous history.
"Hatteras," said the Doctor, "it is enough! we cannot go further!"
"Stop, then," he replied, in a strangely altered voice; "I am going higher."
"No, it is useless; you are at the Pole already."
"No, no! higher, higher!"
"My friend, do you know who is speaking to you? It is I, Doctor Clawbonny."