What is the element of sensuousness in "Ode to a Nightingale"?

Keats' "Ode to a Nightingale" is full of sensuous details. In fact, it is the sensuousness of his imagery that makes him such a great poet. Here are some examples of that bountiful sensuous imagery:

O for a beaker full of the warm south,
Full of the true, the blushful Hippocrene,
With beaded bubbles winking at the brim,
And purple-stainèd mouth;

The beaded bubbles winking at the brim are especially striking. We have all noticed this in a glass of red wine but needed Keats to call our attention to them. The little bubbles all cluster as if they are beaded together. They are iridescent and reflect the dark purple wine below them as well as the light that comes from above. Does anybody take the time to appreciate such tiny details anymore? Or do they all want to have read the poem and put it behind them? The beaded bubbles are in constant motion because they are so fragile. Not one of them can last for long. Each of them will pop. Keats uses the word "winking" to describe the effect perfectly. Each popped bubble is replaced by another bubble as if there are infinite bubbles eager to enjoy their moment of life and light. Keats may have spent a long time looking for those exact words to create the image.

But here there is no light,
Save what from heaven is with the breezes blown
Through verdurous glooms and winding mossy ways.

In his imagination the poet is close to the ground in bushes where nightingales nest. He imagines the faint light is blown through the shadows by the breezes. It is a supernatural kind of lighting effect known only to nightingales.

Fast fading violets cover'd up in leaves;
And mid-May's eldest child,
The coming musk-rose, full of dewy wine,
The murmurous haunt of flies on summer eves.

Keats deviates from the dominant iambic pentameter with "Fast fading violets cover'd up in leaves." This line has a syncopated effect. You can hear it if you read the line aloud. The big white musk-rose full of what Keats calls wine, and which is really a mixture of dew and the flower's own sweet-smelling nectar, evokes an image of a sort of quiet, dimly lighted pub where the flies gather in the evening to drink and converse. This is a fascinating, nearly hypnotic image—for anyone who will take the time to savor such things. F. Scott Fitzgerald must have loved Keats. Fitzgerald's prose is full of Keatsian-type description. He used the words "Tender is the night" as the title for his best novel.

Perhaps the self-same song that found a path
Through the sad heart of Ruth, when, sick for home,
She stood in tears amid the alien corn;
The same that oft-times hath
Charm'd magic casements, opening on the foam
Of perilous seas, in faery lands forlorn.

Those last two lines are spoken just before the poet is called back out of his fantasy into the grim world of reality. The lines represent his effort to express what cannot be expressed. They are the high point of the poem. The faery lands are "forlorn" because nobody believes in them anymore. It is the word "forlorn" that calls Keats back to reality against his will. Unlike the nightingale, he is not immortal. He died at the tender age of twenty-five, a tragic loss to English literature.

Adieu! adieu! thy plaintive anthem fades
Past the near meadows, over the still stream,
Up the hill-side; and now 'tis buried deep
In the next valley-glades:
Was it a vision, or a waking dream?
Fled is that music—Do I wake or sleep?

Those are some examples of the sensuousness which is to be found in "Ode to a Nightingale" and in most of Keats' poetry. His "Ode to a Nightingale" is probably his greatest work.