“Then, captain,” replied the sailor, “let us build a house on the edge of the lake.  Neither bricks nor tools are wanting now.  After having been brickmakers, potters, smelters, and smiths, we shall surely know how to be masons!”

“Yes, my friend; but before coming to any decision we must consider the matter thoroughly.  A natural dwelling would spare us much work, and would be a surer retreat, for it would be as well defended against enemies from the interior as those from outside.”

“That is true, Cyrus,” replied the reporter, “but we have already examined all that mass of granite, and there is not a hole, not a cranny!”

“No, not one!” added Pencroft.  “Ah, if we were able to dig out a dwelling in that cliff, at a good height, so as to be out of the reach of harm, that would be capital!  I can see that on the front which looks seaward, five or six rooms—­”

“With windows to light them!” said Herbert, laughing.

“And a staircase to climb up to them!” added Neb.

“You are laughing,” cried the sailor, “and why?  What is there impossible in what I propose?  Haven’t we got pickaxes and spades?  Won’t Captain Harding be able to make powder to blow up the mine?  Isn’t it true, captain, that you will make powder the very day we want it?”

Cyrus Harding listened to the enthusiastic Pencroft developing his fanciful projects.  To attack this mass of granite, even by a mine, was Herculean work, and it was really vexing that nature could not help them at their need.  But the engineer did not reply to the sailor except by proposing to examine the cliff more attentively, from the mouth of the river to the angle which terminated it on the north.

They went out, therefore, and the exploration was made with extreme care, over an extent of nearly two miles.  But in no place in the bare, straight cliff, could any cavity be found.  The nests of the rock pigeons which fluttered at its summit were only, in reality, holes bored at the very top, and on the irregular edge of the granite.

It was a provoking circumstance, and as to attacking this cliff, either with pickaxe or with powder, so as to effect a sufficient excavation, it was not to be thought of.  It so happened that, on all this part of the shore, Pencroft had discovered the only habitable shelter, that is to say, the Chimneys, which now had to be abandoned.

The exploration ended, the colonists found themselves at the north angle of the cliff, where it terminated in long slopes which died away on the shore.  From this place, to its extreme limit in the west, it only formed a sort of declivity, a thick mass of stones, earth, and sand, bound together by plants, bushes, and grass inclined at an angle of only forty-five degrees.  Clumps of trees grew on these slopes, which were also carpeted with thick grass.  But the vegetation did not extend far, and a long, sandy plain, which began at the foot of these slopes, reached to the beach.