In undramatic poetry the new school, both in England and in France, took its point of departure in a reform against the extravagances of the Marinists, or conceited poets, specially represented in England by Donne and Cowley.  The new poets, both in their theory and practice, insisted upon correctness, clearness, polish, moderation, and good sense.  Boileau’s L’Art Poetique, 1673, inspired by Horace’s Ars Poetica, was a treatise in verse upon the rules of correct composition, and it gave the law in criticism for over a century, not only in France, but in Germany and England.  It gave English poetry a didactic turn and started the fashion of writing critical essays in riming couplets.  The Earl of Mulgrave published two “poems” of this kind, an Essay on Satire, and an Essay on Poetry.  The Earl of Roscommon—­who, said Addison, “makes even rules a noble poetry”—­made a metrical version of Horace’s Ars Poetica, and wrote an original Essay on Translated Verse.  Of the same kind were Addison’s epistle to Sacheverel, entitled An Account of the Greatest English Poets, and Pope’s Essay on Criticism, 1711, which was nothing more than versified maxims of rhetoric, put with Pope’s usual point and brilliancy.  The classicism of the 18th century, it has been said, was a classicism in red heels and a periwig.  It was Latin rather than Greek; it turned to the least imaginative side of Latin literature and found its models, not in Vergil, Catullus, and Lucretius, but in the satires, epistles, and didactic pieces of Juvenal, Horace, and Persius.

The chosen medium of the new poetry was the heroic couplet.  This had, of course, been used before by English poets as far back as Chaucer.  The greater part of the Canterbury Tales was written in heroic couplets.  But now a new strength and precision were given to the familiar measure by imprisoning the sense within the limit of the couplet, and by treating each line as also a unit in itself.  Edmund Waller had written verse of this kind as early as the reign of Charles I. He, said Dryden, “first showed us to conclude the sense most commonly in distichs, which, in the verse of those before him, runs on for so many lines together that the reader is out of breath to overtake it.”  Sir John Denham, also, in his Cooper’s Hill, 1643, had written such verse as this: 

  O, could I flow like thee, and make thy stream
  My great example as it is my theme! 
  Though deep yet clear, though gentle yet not dull,
  Strong without rage, without o’erflowing full.

Here we have the regular flow, and the nice balance between the first and second member of each couplet, and the first and second part of each line, which characterized the verse of Dryden and Pope.

  Waller was smooth, but Dryden taught to join
  The varying verse, the full resounding line,
  The long resounding march and energy divine.