What do the creatures predict where they are?

From the text:

"Where?" they asked. "Where? Where is there?"
"I don't know," the Old-Green-Grasshopper said. "But I'll bet it's somewhere good."
"We are probably at the bottom of a coal mine," the Earthworm said gloomily. "We certainly went
down and down and down very suddenly at the last moment. I felt it in my stomach. I still feel it."
"Perhaps we are in the middle of a beautiful country full of songs and music," the Old-GreenGrasshopper said.
"Or near the seashore," said James eagerly, "with lots of other children down on the sand for me
to play with!"
"Pardon me," murmured the Ladybug, turning a trifle pale, "but am I wrong in thinking that we
seem to be bobbing up and down?"