As a heavy surf assaults some roaring coast,
piling breaker on breaker whipped by the West Wind,
and out on the open sea a crest first rears its head
then pounds down on the shore with hoarse, rumbling thunder
and in come more shouldering crests, arching up and breaking
against some rocky spit, exploding salt foam to the skies –
so wave on wave they came, Achaean battalions ceaseless,
surging on to war.
The Iliad, Book 4, lines 489-496. In an epic simile the Achaean forces advancing to battle are likened to the thunderous ocean surf pounding down on the shore and driven by the West Wind.