Which two sentences contribute to the overall eerie mood of this excerpt from "the cask of amontillado" by edgar allan poe?

The wine sparkled in his eyes and the bells jingled. My own fancy grew warm with the Medoc. We had passed through long walls of piled skeletons, with casks and puncheons intermingling, into the inmost recesses of the catacombs. I paused again, and this time I made bold to seize Fortunato by an arm above the elbow.

"The niter!" I said. "See, it increases. It hangs like moss upon the vaults. We are below the river's bed. The drops of moisture trickle among the bones. Come, we will go back ere it is too late. Your cough--"

"It is nothing," he said; "let us go on. But first, another draught of the Medoc."

I broke and reached him a flagon of De Grave. He emptied it at a breath. His eyes flashed with a fierce light. He laughed and threw the bottle upwards with a gesticulation I did not understand.

I looked at him in surprise. He repeated the movement--a grotesque one.

find the 2 lines then hmu