What was the cub's reaction when he sees teepees rise?

The cub was afraid of the teepees.

The elevation of frames of poles caught his eye; yet this in itself was not so remarkable, being done by the same creatures that flung sticks and stones to great distances. But when the frames of poles were made into tepees by being covered with cloth and skins, White Fang was astounded. It was the colossal bulk of them that impressed him. They arose around him, on every side, like some monstrous quick-growing form of life. They occupied nearly the whole circumference of his field of vision. He was afraid of them. They loomed ominously above him; and when the breeze stirred them into huge movements, he cowered down in fear, keeping his eyes warily upon them, and prepared to spring away if they attempted to precipitate themselves upon him.