Sapphic stanza

The Sapphic stanza, named after Sappho, is an Aeolic verse form spanning four lines (although originally three in the poetry of Sappho and Alcaeus, as there is no line before the final Adonean). Originally the stanza was unrhymed, but during the Middle Ages it adapted a rhyme scheme of ABAB.
Classical Greek and Latin.
The form is two hendecasyllabic verses, and a third verse beginning the same way and continuing with five additional syllables, a trochee, trochee, dactyl, trochee, trochee and a concluding line of dactyl, trochee, given as the stanza's fourth verse in ancient and modern editions, and known as the Adonic or adonean line. 
Using "–" for a long syllable, "∪" for a short syllable, and "x" for an "anceps" (free syllable), and displaying the Adonic as a fourth line:
Sappho.
While Sappho used several metrical forms for her poetry, she is most famous for the Sapphic stanza. Her poems in this meter (collected in Book I of the ancient edition) ran to 330 stanzas, a significant part of her complete works, and of her surviving poetry: fragments 1-42. It is not clear if she created it or if it was already part of the Aeolic tradition. According to Marius Victorinus in "Ars grammatica", the stanza was invented by Alcaeus but then used more frequently by Sappho, and so is more strongly associated with her.
Sappho's most famous poem in this metre is Sappho 31, written in the Aeolic Greek dialect of her home island of Lesbos, which begins as follows:
Other poets.
Sappho's contemporary and countryman, Alcaeus of Mytilene, also used the Sapphic stanza.
A few centuries later, the Roman poet Catullus admired Sappho's work and used the Sapphic meter in two poems, Catullus 11 and Catullus 51. The latter is a rough translation of Sappho 31. Sapphics were also used by Horace in several of his "Odes", including Ode 1.22:
The Sapphic stanza was one of the few classical quantitative meters to survive into the Middle Ages, when accentual rather than quantitative prosody became the norm. Many Latin hymns were written in Sapphic stanzas, including the famous hymn for St John the Baptist which gave the original names of the sol-fa scale:
Ut queant laxis resonare fibris/
Mira gestorum famuli tuorum/
Solve polluti labii reatum/
Sancte Joannes
Modern adaptations.
English.
Though some English poets attempted quantitative effects in their verse, quantity is not phonemic in English. So imitations of the Sapphic stanza are typically structured by replacing "long" with "stressed" syllables, and "short" with "unstressed" syllables (and often additional alterations, as exemplified below).
The Sapphic stanza was imitated in English, using a line articulated into three sections (stressed on syllables 1, 5, and 10) as the Greek and Latin would have been, by Algernon Charles Swinburne in a poem he simply called "Sapphics":
<poem style="margin-left:2em">
So the goddess fled from her place, with awful
Sound of feet and thunder of wings around her;
While behind a clamour of singing women
</poem>
Thomas Hardy chose to open his first verse collection Wessex Poems and other verses 1898 with "The Temporary the All," a poem in Sapphics, perhaps as a declaration of his skill and as an encapsulation of his personal experience.
<poem style="margin-left:2em">
Change and chancefulness in my flowering youthtime,
Set me sun by sun near to one unchosen;
Wrought us fellowly, and despite divergence,
</poem>
Rudyard Kipling wrote a tribute to William Shakespeare in Sapphics called "The Craftsman". He hears the line articulated into four, with stresses on syllables 1, 4, 6, and 10 (called a 'schoolboy error' by classical scholar L. P. Wilkinson, arising from a misunderstanding of Horace's regularisation of the 4th syllable as a long and his frequent use of the 5th-element caesura in his Sapphics). His poem begins:
<poem style="margin-left:2em">
Once, after long-drawn revel at The Mermaid,
He to the overbearing Boanerges
Jonson, uttered (if half of it were liquor
</poem>
Allen Ginsberg also experimented with the form:
<poem style="margin-left:2em">
Red cheeked boyfriends tenderly kiss me sweet mouthed
under Boulder coverlets winter springtime
hug me naked laughing & telling girl friends
</poem>
Isaac Watts penned "The Day of Judgment" subtitled "An Ode Attempted in English Sapphic" (here are the third and fourth stanzas, the full poem is at this link):
<poem style="margin-left:2em">
Such shall the noise be and the wild disorder,
Such the dire terror, when the great Archangel
Tears the strong pillars of the vault of heaven,
Breaks up old marble, the repose of princes;
See the graves open, and the bones arising,
</poem>
Australian Classicist and poet John Lee wrote a Sapphic stanza about the impossibility of writing Sapphic stanzas in English:
<poem style="margin-left:2em">
Making Sapphics isn't that easy, shackling
Our reluctant language with trochees. Since you
First begot them, songstress of Lesbos, keep them.
</poem>
(the poem exists also in a Latin version).
The Australian poet John Tranter has also written a poem ("Writing in the Manner of Sappho") in two Sapphic stanzas about the difficulty of writing Sapphics in English:
<poem style="margin-left:2em">
Writing Sapphics well is a tricky business.
Lines begin and end with a pair of trochees;
in between them dozes a dactyl, rhythm
like a drunk asleep at a party. Ancient
Greek — the language seemed to be made for Sapphics,
not a worry; anyone used to English
</poem>
The Oxford classicist Armand D'Angour has created mnemonics to illustrate the difference between Sapphics heard as 1) a four-beat line (as in Kipling) and 2) in the (correct) three-beat measure, as follows:
<poem style="margin-left:2em">
1. Four-beat: 
Conquering Sappho's not an easy business:
Masculine ladies cherish independence.
Only good music penetrates the souls of
2. Three-beat:
Independent metre is overrated:
What's the point if nobody knows the dance-form?
Wisely, Sappho chose to create a stately
</poem>
Notable contemporary Sapphic poems include "Sapphics for Patience" by Annie Finch, "Dusk: July" by Marilyn Hacker, "Buzzing Affy" (a translation of "An Ode to Aphrodite") by Adam Lowe, and "Sapphics Against Anger" by Timothy Steele.
Other languages.
The Sapphic stanza has been very popular in Polish literature since the 16th century. It was used by many poets. Sebastian Klonowic wrote a long poem, Flis, using the form. The formula of 11/11/11/5 syllables was so attractive that it can be found in other forms, among others the Słowacki stanza: 11a/11b/11a/5b/11c/11c.
In 1653, Paul Gerhardt used the Sapphic strophe format in the text of his sacred morning song "Lobet den Herren alle, die ihn ehren". Sapphic stanza was often used in poetry of German Humanism and Baroque. It is also used in hymns such as "Herzliebster Jesu" by Johann Heermann.