froth up

The Spirit mourn'd "Adieu!"—dissolv’d, and left / The atom darkness in a slow turmoil; / As when of healthful midnight sleep bereft, / Thinking on rugged hours and fruitless toil, / We put our eyes into a pillowy cleft, / And see the spangly gloom froth up and boil: / It made sad Isabella’s eyelids ache, / And in the dawn she started up awake; …