Frank J. Wilstach, comp. A Dictionary of Similes. 1916.

Unseen

Not seen, like arrows shot by night.
—Buddha

Unseen, like the wind.
—Edmund Gosse

Crept stealthily and unseen, like earth-worms to a carcase.
—Edward Bulwer-Lytton

More unseen
Than Satan in his exile.
—John Keats

Unseen as a disbanded rainbow.
—Sydney Munden

Unseen, as lamps in sepulchres.
—Alexander Pope

Like a star of Heaven,
In the broad daylight,
Thou art unseen.
—Percy Bysshe Shelley