All stopped about fifty feet from half-a-dozen animals of a large size, with strong horns bent back and flattened towards the point, with a woolly fleece, hidden under long silky hair of a tawny color.

They were not ordinary sheep, but a species usually found in the mountainous regions of the temperate zone, to which Herbert gave the name of the musmon.

"Have they legs and chops?" asked the sailor.

"Yes," replied Herbert.

"Well, then, they are sheep!" said Pencroft.

The animals, motionless among the blocks of basalt, gazed with an astonished eye, as if they saw human bipeds for the first time. Then their fears suddenly aroused, they disappeared, bounding over the rocks.

"Good-bye, till we meet again," cried Pencroft, as he watched them, in such a comical tone that Cyrus Harding, Gideon Spilett, Herbert, and Neb could not help laughing.

The ascent was continued. Here and there were traces of lava. Sulphur springs sometimes stopped their way, and they had to go round them. In some places the sulphur had formed crystals among other substances, such as whitish cinders made of an infinity of little feldspar crystals.

In approaching the first plateau formed by the truncating of the lower cone, the difficulties of the ascent were very great. Towards four o'clock the extreme zone of the trees had been passed. There only remained here and there a few twisted, stunted pines, which must have had a hard life in resisting at this altitude the high winds from the open sea. Happily for the engineer and his companions the weather was beautiful, the atmosphere tranquil; for a high breeze at an elevation of three thousand feet would have hindered their proceedings. The purity of the sky at the zenith was felt through the transparent air. A perfect calm reigned around them. They could not see the sun, then hid by the vast screen of the upper cone, which masked the half-horizon of the west, and whose enormous shadow stretching to the shore increased as the radiant luminary sank in its diurnal course. Vapor--mist rather than clouds--began to appear in the east, and assume all the prismatic colors under the influence of the solar rays.

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.