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The Mysterious Island · Chapter

XVIII explained

The colonists successfully lower the lake level using nitroglycerine, revealing an old outlet that leads to a vast subterranean cavern.

What happens

The colonists successfully lower the lake level using nitroglycerine, revealing an old outlet that leads to a vast subterranean cavern. They explore the passage, discovering a magnificent granite chamber which they name 'Granite House.' The chapter ends with the mystery of Top's barking at a deep well, hinting at unknown presences.

Themes in this chapter

  • Colonization and Civilization

    The discovery and naming of 'Granite House' symbolizes the colonists' effort to establish a permanent, organized home on the island.

  • Nature and the Sublime

    The awe-inspiring description of the cavern's natural architecture evokes the sublime power of nature.

  • Providence and Mystery

    Top's unexplained barking at the well and the engineer's murmurs suggest a hidden, perhaps providential, presence.

Characters to notice

  • Cyrus Smith

    Leads the exploration, devises the nitroglycerine blast, and names the new home 'Granite House.'

  • Pencroff

    Eager to explore, expresses wonder at the engineer's feats, and helps with the pick work.

  • Herbert Brown

    Enthusiastic about the discovery, suggests the name for the cavern, and assists in gathering torches.

  • Neb

    Helps with the picks and torches, shows reverence by removing his hat in the cavern.

  • Gideon Spilett

    Curious about the mystery of Top's barking, participates in the exploration.

  • Top

    Barks furiously at a deep well, alerting the colonists to something unknown.

Key passages

  • Yes, I am convinced that Top knows more than we do about many things!

    Cyrus Smith suspects that Top has knowledge of something the colonists do not.

    Highlights the ongoing mystery and the dog's role as an intuitive guide.

  • My friends, when we shall have lighted the interior of this place, when we shall have arranged our chambers, our storerooms, our offices in the left-hand portion, we will still have this splendid cavern, which shall be our study and our museum!

    Smith envisions transforming the cavern into a functional and cultural home for the colonists.

    Reflects the theme of colonization and the civilizing impulse.