that the
nitro-glycerine was on a level with the opening; then he threw a few
drops of it on the surface of the rock, above which the mass of iron was
already suspended.

This done, Harding lit the end of the sulphured fiber, and leaving the
place, he returned with his companions to the Chimneys.

The fiber was intended to burn five and twenty minutes, and, in fact,
five and twenty minutes afterwards a most tremendous explosion was
heard. The island appeared to tremble to its very foundation. Stones
were projected in the air as if by the eruption of a volcano. The shock
produced by the displacing of the air was such, that the rocks of the
Chimneys shook. The settlers, although they were more than two miles
from the mine, were thrown on the ground.

They rose, climbed the plateau, and ran towards the place where the bank
of the lake must have been shattered by the explosion.

A cheer escaped them! A large rent was seen in the granite! A rapid
stream of water rushed foaming across the plateau and dashed down a
height of three hundred feet on to the beach!

Chapter 18

Cyrus Harding's project had succeeded, but, according to his usual
habit he showed no satisfaction; with closed lips and a fixed look, he
remained motionless. Herbert was in ecstasies, Neb bounded with joy,
Pencroft nodded his great head, murmuring these words,--

"Come, our engineer gets on capitally!"

The nitro-glycerine had indeed acted powerfully. The opening which it
had made was so large that the volume of water which escaped through
this new outlet was at least treble that which before passed through the
old one. The result was, that a short time after the operation the level
of the lake would be lowered two feet, or more.

The settlers went to the Chimneys to take some pickaxes, iron-tipped
spears, string made of fibers, flint and steel; they then returned to
the plateau, Top accompanying them.

On the way the sailor could not help saying to the engineer,--

"Don't you think, captain, that by means of that charming liquid you
have made, one could blow up the whole of our island?"

"Without any doubt, the island, continents, and the world itself,"
replied the engineer. "It is only a question of quantity."

"Then could you not use this nitro-glycerine for loading firearms?"
asked the sailor.

"No, Pencroft; for it is too explosive a substance. But it would be easy
to make some guncotton, or even ordinary powder, as we have azotic