For all their being yoked together in the minds of the public, the two are quite different poets, and were critical of one another's work, writes MATTHEW SWEENEY

KEATS AND Shelley were not friends. Well, they saw a fair bit of each other in 1817, before Shelley left England, but as fellow poet Leigh Hunt said: "Keats did not take to Shelley as kindly as Shelley did to him." They were quite critical of each other's work, too, initially at least. Shelly wrote to Keats, after reading his first publication Endymion, admonishing him: "In poetry I have sought to avoid system and mannerism." Keats replied tartly: "You might curb your magnanimity, and be more of an artist, and load every rift of your subject with ore."

For all their being yoked together in the mind of the public, they are quite different poets. Shelley was an idealist, interested in politics and philosophy. His wife, Mary Shelley, added a note to Shelley's mythical long poem Prometheus Unbound: "Shelley believed that mankind had only to will that there would be no evil, and there would be none." There is often a great sweep to his poetry – Hymn to Intellectual Beautybegins like this: "The awful shadow of some unseen Power / Floats though unseen among us." Indeed! His passionately indignant response to the Peterloo massacre of 1819, The Mask of Anarchy, included these lines very early on:

“I met Murder on the way –

He had a face like Castlereagh –

Very smooth he looked, yet grim

Seven bloodhounds followed him.

All were fat, and well they might

Be in admirable plight,

For one by one, and two by two,

He tossed them human hearts to chew

Which from his wide cloak he drew.”

His last poem, published posthumously, the terza rima, Dante-influenced The Triumph of Life, earned these words in a review by the critic Hazlitt: "The poem entitled The Triumph of Lifeis in fact a new and terrific Dance of Death." When Keats died a year before him, Shelley produced a pastoral elegy, Adonais, modelled on Greek poems of the second century BC. It includes some stunning writing, such as:

“Life, like a dome of many-coloured glass,

Stains the white radiance of Eternity,

Until Death tramples it to fragments.”

His famous sonnet, Ozymandias, is one of the most loved poems in the language – and, unbelievably, emerged from a writing game where Shelley, Keats and Leigh Hunt proposed a sonnet on a set subject, the Nile.

I cannot leave Shelley without mentioning his great affinity with the natural world – look at his swooping Ode to the West Windand the wonderfully inventive yet exact The Cloud, where a cloud speaks:

“I wield the flail of the lashing hail

And whiten the green plains under,

And then again I dissolve it in rain,

And laugh as I pass in thunder.

I sift the snow on the mountains below,

And their great pines groan aghast”

Any young poet could learn from that.

KEATS WAS AFTER a more unobtrusive poetry that had no palpable design on the reader. His work is known for the startling accuracy of its imagery, and his talent for evoking atmosphere. The poem that propelled him to attention was the deft sonnet On First Looking into Chapman's Homer, with its terrific ending:

“Then felt I like some watcher of the skies

When a new planet swims into his ken;

Or like stout Cortez when with eagle eyes

He stared at the Pacific – and all his men

Look’d at each other with a wild surmise –

Silent, upon a peak in Darien.”

Despite the notice this poem attracted, Keats had a rocky ride at the beginning. Endymion got some harsh reviews. The Quarterly Review, for example, described it as: "Cockney poetry; which may be defined to consist of the most incongruous ideas in the most uncouth language." Things improved, fortunately, and Keats went on to write in the spring of 1819 the dense, rich odes that made his name: Ode to Psyche, Ode to a Nightingale, Ode on a Grecian Urn, Ode on Melancholy, and the slightly later To Autumn:

“Season of mists and mellow fruitfulness,

Close bosom friend of the maturing sun;

Conspiring with him how to load and bless

With fruit the vines that round the

thatch-eaves run;

To bend with apples the moss’d cottage trees,

And fill all fruit with ripeness to the core”

It was another kind of poem, however, that released these – that shook him out of a melancholy that had left him listless the previous winter. I'm speaking of the spooky vampire ballad La Belle Dame sans Mercithat begins with:

“O, what can ail thee, knight-at-arms,

Alone and palely loitering?”

Note the telling adverb – and later on, when the knight has a vision of previous victims of the femme fatale, this is pointed out again:

“I saw pale kings, and princes too,

Pale warriors, death-pale were they all”

Bram Stoker clearly drew on this to create the female vampires in Dracula. Keats has another vampire poem, Lamia, an exuberant narrative written in slinky rhyming couplets, where a young man falls in love with a supernatural woman, who at the beginning of the poem is in the form of a beautiful snake, and entreats the god Hermes to release her:

“I was a woman, let me have once more

A woman’s shape, and charming as before.

I love a youth of Corinth – O the bliss!

Give me my woman’s form, and place me

where he is.”

Hermes does, and it turns out bad, but the poem is a sizzling read. Check it out.

Jane Campion's Bright Staris on release

Matthew Sweeney's most recent volume of poetry is Black Moon