I copied this page intact from http://www.english.upenn.edu/~afilreis/88/sonnet.html, because that link is very slow. I hope this is a "fair use", and not a copyright infringement. [- DM]
and the sestet, or second division, consisting of six lines rhyming
cdecde, cdccdc, or cdedce.
On this twofold division of the Italian sonnet Charles Gayley notes: "The octave bears the burden; a doubt, a problem, a reflection, a query, an historical statement, a cry of indignation or desire, a Vision of the ideaL The sestet eases the load, resolves the problem or doubt, answers the query, solaces the yearning, realizes the vision." Again it might be said that the octave presents the narrative, states the proposition or raises a question; the sestet drives home the narrative by making an abstract comment, applies the proposition, or solves the problem. So much for the strict interpretation of the Italian form; as a matter of fact English poets have varied these items greatly. The octave and sestet division is not always kept; the rhyme-scheme is often varied, but within limits--no Italian sonnet properly allowing more than five rhymes. Iambic pentameter is essentially the meter, but here again certain poets have experimented with hexameter and other meters.
The English (Shakespearean) sonnet, on the other hand, is so different >from the Italian (though it grew from that form) as to permit of a separate classification. Instead of the octave and sestet divisions, this sonnet characteristically embodies four divisions: three quatrains (each with a rhyme-scheme of its own) and a rhymed couplet. Thus the typical rhyme-scheme for the English sonnet is
abab cdcd efef gg.The couplet at the end is usually a commentary on the foregoing, an epigrammatic close. The Spenserian sonnet combines the Italian and the Shakespearean forms, using three quatrains and a couplet but employing linking rhymes between the quatrains, thus
abab bcbc cdcd ee.Certain qualities common to the sonnet as a form should be noted. Its definite restrictions make it a challenge to the artistry of the poet and call for all the technical skill at the poet's command. The more or less set rhyme patterns occurring regularly within the short space of fourteen lines afford a pleasant effect on the ear of the reader, and can Create truly musical effects. The rigidity of the form precludes a too great economy or too great prodigality of words. Emphasis is placed on exactness and perfection of expression.
The sonnet as a form developed in Italy probably in the thirteenth century. Petrarch, in the fourteenth century, raised the sonnet to its greatest Italian perfection and so gave it, for English readers, his own name.
The form was introduced into England by Thomas Wyatt, who translated Petrarchan sonnets and left over thirty examples of his own in English. Surrey, an associate, shares with Wyatt the credit for introducing the form to England and is important as an early modifier of the Italian form. Gradually the Italian sonnet pattern was changed and since Shakespeare attained fame for the greatest poems of this modified type his name has often been given to the English form.
Among the most famous sonneteers in England have been Shakespeare, Milton, Wordsworth, and D. G. Rossetti. Longfellow, Jones Very, G. H. Boker, and E. A. Robinson are generally credited with writing some of the best sonnets in America. With the interest in this poetic form, certain poets following the example of Petrarch have written a series of sonnets linked one to the other and dealing with some unified subject. Such series are called sonnet sequences.
Some of the most famous sonnet sequences in English literature are those by Shakespeare (154 in the group), Sidney's Astrophel and Stella, Spenser's Amoretti, Rossetti's House of Life, and Mrs. Browning's Sonnets from the Portuguese. William Ellery Leonard, Elinor Wylie, Edna St. Vincent Millay, and W. H. Auden have done distinguished work in the sonnet and the sonnet sequence in this century. The brevity of the form favors concentrated expression of idea or passion.