There is a vagueness, an abstractness, an ethereal quality about the poetry of Shelly. It is the poetry of a man living not earth, but in the aerial regions above. This ethereal in his poetry is due to the want in
general, of "a sound subject-mater". Even Adonais which is a poem of grief on the death of Keats , he preserves a sense of unreality and calls in many shadowy allegorical figures.
He talks of metaphysical powers like intellectual beauty and of vague things like the golden age of mankind. His imagery, too,is abstract and divorced from human lofe as he takes delight in giving us pictures of the shifting and changeling phenomena of nature like clouds, sunsets, winds, sky and ocean. Also he employs inverse similes which instead of making his meaning concrete, render it vague. "Like wrecks of a dissolving dream". "Like ghost from an enchanter fleeing," "like the hues and harmonies of evening " are examples of his inverse similes.