Five hundred feet only separated the explorers from the plateau, which they wished to reach so as to establish there an encampment for the night, but these five hundred feet were increased to more than two miles by the zigzags which they had to describe.  The soil, as it were, slid under their feet.

The slope often presented such an angle that they slipped when the stones worn by the air did not give a sufficient support.  Evening came on by degrees, and it was almost night when Cyrus Harding and his companions, much fatigued by an ascent of seven hours, arrived at the plateau of the first cone.  It was then necessary to prepare an encampment, and to restore their strength by eating first and sleeping afterwards.  This second stage of the mountain rose on a base of rocks, among which it would be easy to find a retreat.  Fuel was not abundant.  However, a fire could be made by means of the moss and dry brushwood, which covered certain parts of the plateau.  While the sailor was preparing his hearth with stones which he put to this use, Neb and Herbert occupied themselves with getting a supply of fuel.  They soon returned with a load of brushwood.  The steel was struck, the burnt linen caught the sparks of flint, and, under Neb’s breath, a crackling fire showed itself in a few minutes under the shelter of the rocks.  Their object in lighting a fire was only to enable them to withstand the cold temperature of the night, as it was not employed in cooking the bird, which Neb kept for the next day.  The remains of the capybara and some dozens of the stone-pine almonds formed their supper.  It was not half-past six when all was finished.

Cyrus Harding then thought of exploring in the half-light the large circular layer which supported the upper cone of the mountain.  Before taking any rest, he wished to know if it was possible to get round the base of the cone in the case of its sides being too steep and its summit being inaccessible.  This question preoccupied him, for it was possible that from the way the hat inclined, that is to say, towards the north, the plateau was not practicable.  Also, if the summit of the mountain could not be reached on one side, and if, on the other, they could not get round the base of the cone, it would be impossible to survey the western part of the country, and their object in making the ascent would in part be altogether unattained.

The engineer, accordingly, regardless of fatigue, leaving Pencroft and Neb to arrange the beds, and Gideon Spilett to note the incidents of the day, began to follow the edge of the plateau, going towards the north.  Herbert accompanied him.

The night was beautiful and still, the darkness was not yet deep.  Cyrus Harding and the boy walked near each other, without speaking.  In some places the plateau opened before them, and they passed without hindrance.  In others, obstructed by rocks, there was only a narrow path, in which two persons could not walk abreast.  After a walk of twenty minutes, Cyrus Harding and Herbert were obliged to stop.  From this point the slope of the two cones became one.  No shoulder here separated the two parts of the mountain.  The slope, being inclined almost seventy degrees, the path became impracticable.