The fuel, made of well-prepared fagots, was laid on the ground and surrounded with several rows of dried bricks, which soon formed an enormous cube, to the exterior of which they contrived air-holes.

The work lasted all day, and it was not till the evening that they set fire to the fagots.

No one slept that night, all watching carefully to keep up the fire.
The operation lasted forty-eight hours, and succeeded perfectly.

It then became necessary to leave the smoking mass to cool, and during this time Neb and Pencroft, guided by Cyrus Harding, brought, on a hurdle made of interlaced branches, loads of carbonate of lime and common stones, which were very abundant, to the north of the lake.

These stones, when decomposed by heat, made a very strong quicklime, greatly increased by slacking, at least as pure as if it had been produced by the calcination of chalk or marble.