Here a startling sight met his view.
The ground seemed to be sinking under the weight of the Ranger.
“Good Heaven! What’s this?” he gasped.
“There must be soft ground under us,” replied Vaneyke.
“I’ll raise the boat again.”
He grasped the gyroscope lever and turned it, but though the wheels spun around the ice ship did not rise.
Her runners and wheels had become caught and held fast by the treacherous ground under her.
CHAPTER VIII.
THE MAMMOTH.
Leaving the boat in the professor’s care, Frank rushed out on deck, and peering over at the ground, he saw that it was sinking down beneath the weight of the boat.
The ice covering had given way, exposing a muddy marsh, up from which a terrible stench was rising.