Of all his verse, it is these songs about nature and love that every one knows and likes best. And, in fact, many of them seem to satisfy what is perhaps the ultimate test of true poetry: they sometimes have the power, which makes poetry akin to music, of suggesting by means of words something which cannot possibly be expressed in words. Obviously the test is impossible to use with any objective certainty, but, for a reason which will appear, it seems capable of a fairly straightforward application to Shelley's work. First we may observe that, just as the sight of some real scene--not necessarily a sunset or a glacier, but a ploughed field or a street-corner--may call up emotions which "lie too deep for tears" and cannot be put into words, this same effect can be produced by unstudied descriptions. Wordsworth often produces it: "I wandered lonely as a cloud That floats on high o'er vales and hills, When all at once I saw a crowd, A host of golden daffodils." Now, in the description of natural scenes that kind of effect is beyond Shelley's reach, though he has many pictures which are both detailed and emotional. Consider, for instance, these lines from 'The Invitation' (1822). He calls to Jane Williams to come away "to the wild woods and the plains," "Where the lawns and pastures be, And the sandhills of the sea;-- Where the melting hoar-frost wets The daisy-star that never sets, And wind-flowers, and violets, Which yet join not scent to hue, Crown the pale year weak and new; When the night is left behind In the deep east, dun and blind, And the blue moon is over us, And the multitudinous Billows murmur at our feet, Where the earth and ocean meet, And all things seem only one In the universal sun." This has a wonderful lightness and radiance. And here is a passage of careful description from 'Evening: Ponte a Mare, Pisa': "The sun is set; the swallows are asleep; The bats are flitting fast in the gray air; The slow soft toads out of damp corners creep, And evening's breath, wandering here and there Over the quivering surface of the stream, Walkes not one ripple from its summer dream. There is no dew on the dry grass to-night, Nor damp within the shadow of the trees; The wind is intermitting, dry and light; And in the inconstant motion of the breeze The dust and straws are driven up and down, And whirled about the pavement of the town."