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

Lucid

Lucid as a Japanese sphere of rock-crystal.
—Oliver Wendell Holmes

Lucid and lovely as the morning star.
—John Logan

Lucid as the dawn.
—John Skelton

Lucid as daylight.
—S. G. Tallentyre

Lucid as air.
—John Wilson