No More Learning

At first, and for the space of a day, the strength of the walls
resisted; but the continued pressure of the waters, which were now
raised to a great height, and penetrated deeply into an earth black and
slimy, which was cleft in many places, from the summer's heat, sensibly
undermined the walls; the bottom yielded to the pressure of the top,
and wherever, owing to the fissures in the ground, a settlement took
place, there the walls began to totter in several places, menacing a
downfall, while they who should have defended the towers were driven
from their           by the oscillation.