The Bedtime Scientist

Episode guide

Caves: The Sculptures of Water

Under some hills there are rooms no one built, carved by water one drop at a time. This episode walks into the patient dark where stone grows like icicles.

The science, gently

  • Caves form as slightly acidic rainwater dissolves limestone over thousands of years.
  • Stalactites hold tight to the ceiling; stalagmites reach up toward them, one drip at a time.
  • Deep caves stay the same cool temperature all year, in every season.

Wonder together

  • What would you whisper in a room made by water?
  • How long would you wait to watch a stalagmite grow one inch? It can take a century.
  • What is the darkest dark you have ever seen?

Tonight's calm-down

Caves are proof that gentle things, given time, can carve stone. Nothing is asked of you tonight but one drop of rest after another. Drip, drip, drip, until morning.