Albert Barnes Commentary Job 41:20

"Out of his nostrils a smoke goeth, As of a boiling pot and [burning] rushes." — Job 41:20 (ASV)

Out of his nostrils goeth smoke - See the quotations on Job 41:19. This appearance of the crocodile, or alligator, has been often noticed.

Bertram, in his "Travels in North and South Carolina," p. 116, says, "While I was seeking a place of rest, I encountered an alligator that in the neighboring lake rushed through the canes that grew on its banks. He inflated his enormous body, and swung his tail high in the air. A thick smoke streamed from his wide-open nostrils, with a sound that made the earth tremble." Rosenmuller, "Alte u. neue Morgenland," No. 778.

As out of a seething-pot - A pot that is boiling. Literally, "a blown pot;" that is, a pot under which the fire is blown, or kindled.

Or caldron - Any kettle. The same word is used to denote a reed or bulrush, or a rope made of reeds (Isaiah 9:14; Job 41:1).