Metre (poetry) of over some two-and-a-half millennia. Beginning with the earlier recorded forms: the Classic of Poetry tends toward couplets of four-character lines, grouped in rhymed quatrains; and, the Chuci follows this to some extent, but moves toward variations in line length. Han Dynasty poetry tended towards the variable line-length forms of the folk ballads and the Music Bureau yuefu. Jian'an poetry, Six Dynasties poetry, and Tang Dynasty poetry tend towards a poetic metre based on fixed-length lines of five, seven, (or, more rarely six) characters/verbal units tended to predominate, generally in couplet/quatrain-based forms, of various total verse lengths. The Song poetry
Decasyllabic quatrain lines of verse in 304 stanzas, each with a period at the end to show a "completeness" in each stanza. While the form had achieved fame with other poets of Dryden's era and was considered "fashionable" by figures of the literary world, Dryden's poem quickly became known as the standard-bearer of the genre. In 1751, Thomas Gray published "Elegy Written in a Country Churchyard", composed in the heroic stanza. Written in iambic pentameter, the poem followed the same metrical and structural patterns seen in "Annus Mirabilis", but the use of the poetic form in an elegy gave it the title