Reviewing the poems we’ve read so far, it’s clear enough that they all share features that we can identify and describe as sonnet-like: fourteen lines long, following a regular rhyme-scheme (though the Lowell ignores that rule!) and almost all following English poetry’s most familiar and reliable metre, technically known as iambic pentameter. (Five ‘feet’ of the two-syllable type called ‘iambs’, that sounds like de-dump de-dump de-dump de-dump de-dump..). **
But we’ve also seen different variants to the form, from the Petrarchan to the Shakespearean, which enter the language and are accepted and taken up by other writers.
At the end of the nineteenth century this kind of measured evolution begins to break down, and literary modernism follows modernism in the visual arts by privileging individual creativity over established norms. Formal experimentation becomes an approach to personal expressiveness, but also as a way of helping see things afresh.
Seeing things afresh is precisely what the poetry of Gerard Manley Hopkins was about. A Jesuit priest (see the loooong biography at his Poetry Foundation page he arrived in Ireland to teach at University College Dublin in 1884. His poetry followed an increasingly individualistic, if not eccentric path: he invented words and dug deep into dialect and archaic vocabularies, developed a metrical system he called ‘sprung rhthym’, and – where we come in – a version of the fourteener he called a ‘curtal’ [think ‘curtailed’ or shortened] sonnet.
The curtal sonnet, according to Wikipedia, ‘is an eleven-line (or, more accurately, ten-and-a-half-line) sonnet, but rather than the first eleven lines of a standard sonnet it consists of precisely ¾ of the structure of a Petrarchan sonnet shrunk proportionally. The octave of a sonnet becomes a sestet and the sestet a quatrain plus an additional "tail piece." That is, the first eight lines of a sonnet are translated into the first six lines of a curtal sonnet and the last six lines of a sonnet are translated into the last four and a half lines of a curtal sonnet.‘
That’s the dry technical description. Here it is in full flight…
Pied Beauty
Glory be to God for dappled things—
For skies of couple-colour as a brinded cow;
For rose-moles all in stipple upon trout that swim;
Fresh-firecoal chestnut-falls; finches' wings;
Landscape plotted and pieced—fold, fallow, and plough;
And áll trádes, their gear and tackle and trim.
All things counter, original, spare, strange;
Whatever is fickle, freckled (who knows how?)
With swift, slow; sweet, sour; adazzle, dim;
He fathers-forth whose beauty is past change:
Praise him.