Cauldron Bubble by Robby Edwards
Yellowstone National Park, July 2006
Double, double toil and trouble;
Fire burn, and cauldron bubble.
~William Shakespeare — MACBETH; Act IV, scene 1
Crested Pool churns at a slow boil while the clouds in the sky at sunset are reflected in the water surrounding it.
The depth of Crested Pool is 42 feet and water in it maintains a constant boil, but may shift between just simmering or a violent boil, when the water may as high as 8 to 10 feet.