Frank J. Wilstach, comp. A Dictionary of Similes. 1916.
Unshaken
Unshaken like a Thracian hill.
—Richard Glover
Like a rock in the sea, stands unshaken; like a rock in the sea before the rush and crash of waters, which, amid thousands of breaking waves, is fixed by its own weight; the crags and the spray-foamed stones roar about it in vain, and the lashed seaweed falls idly by its side.
—Virgil