It is written in a three-stanza structure with a variable rhyme scheme. Each stanza is eleven lines long. In each stanza, the first part is made up of the first four lines following an ABAB rhyme scheme. The second part made up of the last seven lines is arranged CDEDCCE in the first stanza and CDECDDE in the second and third stanzas.
"To Autumn" is one of the simplest of Keats's odes. The extraordinary achievement of this poem lies in its ability to suggest, explore, and develop a rich abundance of themes without ever ruffling its calm, gentle, and lovely description of autumn. It shows Keats's speaker paying homage to a particular goddess--in this case, the deified season of Autumn. The selection of this season implicitly takes up the themes of temporality, mortality, and change taken up by the earlier odes of Keats. Autumn in Keats's ode is a time of warmth and plenty, but it is perched on the brink of winter's desolation, as the bees enjoy "later flowers," the harvest is gathered from the fields, the lambs of spring are now "full grown," and, in the final line of the poem, the swallows gather for their winter migration. The understated sense of inevitable loss in that final line makes it one of the most moving moments in all of poetry; it can be read as a simple, uncomplaining summation of the entire human condition.
Despite the coming chill of winter, the late warmth of autumn provides Keats's speaker with ample beauty to celebrate: the cottage and its surroundings in the first stanza, the agrarian haunts of the goddess in the second, and the locales of natural creatures in the third. Keats's speaker is able to experience these beauties in a sincere and meaningful way because of the lessons he has learned in the previous odes: He is no longer indolent, no longer committed to the isolated imagination (as in "Psyche"), no longer attempting to escape the pain of the world through ecstatic rapture (as in "Nightingale"), no longer frustrated by the attempt to eternalize mortal beauty or subject eternal beauty to time (as in "Urn"), and no longer able to frame the connection of pleasure and the sorrow of loss only as an imaginary heroic quest (as in "Melancholy").
In "To Autumn," the image of Autumn winnowing and harvesting is an explicit metaphor for artistic creation. The act of creation is pictured as a kind of self-harvesting in another poem; the pen harvests the fields of the brain, and books are filled with the resulting "grain." In "To Autumn," the metaphor is developed further; the sense of coming loss that permeates the poem confronts the sorrow underlying the season's creativity. When Autumn's harvest is over, the fields will be bare, the swaths with their "twined flowers" cut down, the cider-press dry, the skies empty. But the connection of this harvesting to the seasonal cycle softens the edge of the tragedy. In time, spring will come again, the fields will grow again, and the birdsong will return. Abundance and loss, joy and sorrow, song and silence are as intimately connected as the twined flowers in the fields. What makes "To Autumn" beautiful is that it brings an engagement with that connection out of the realm of mythology and fantasy and into the everyday world. The poet has learned that an acceptance of mortality is not destructive to an appreciation of beauty and has gleaned wisdom by accepting the passage of time.
An interpretaion from John:
In the second stanza the poet personifies autumn as a women performing various activities in a way to portray autumn. Also this marks a transition in the poem where in the first stanza it portrays an image of rushing things, activity....in the second the activities start to slow down(use of words like "hours by hours", "sound asleep") And this overall I feel is symbolic of the transition in the seasons as well i.e. from summer to autumn.
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