[Sidenote: His perfecting of M.E. verse.]
For his work is there, and it is incontestably--whatever its author had read or not read--the logical and biological continuation and perfecting of all that had gone before from Godric and the _Paternoster_. He begins with the fluent octosyllable and the melodious and usefully stringent rhyme-royal, as well as other more or less elaborate stanzas. He communicates to the couplet[67] a greater combination of order and variety than it had ever known in English; he makes of the stanza,[68] in the case of rhyme-royal, the most perfect formal arrangement of verse that English had yet seen. Later he takes up,[69] very probably because he had written so many separate examples of it in rhyme-royal itself at the close of each stanza, the _decasyllabic_ couplet, and makes of that something greater still--a metrical instrument or vehicle escaping at once the scanty content and slightly insignificant bearing of the octosyllable, the elaborateness and rather melancholy quality of rhyme-royal. In doing this it is inevitable that, as Spenser did in parallel case afterwards, he should lean rather towards precision than towards great laxity and luxuriance of form; for things needed order. But he sets the example of that variation of pause in rhyme-royal which was fortunately taken as a rule, and which preserved for English one of the very greatest means of metrical achievement. In the octosyllable he reproduced knowingly, and with definite apology, that "failing of a syllable" which gives acephalous or trochaic alternation, and which all the greatest masters of the metre, except (following Gower) William Morris, have imitated. And he broke up the lines very largely by conversation-fragments, by putting full stops at the end of the first line of a couplet, and by making a whole paragraph end at the same place.
But next to his provision of a perfectly finished stanza--in other words, of a complete, and _pro tanto_ final, prosodic result--in rhyme-royal, the most important thing done by Chaucer in this department was the arranging and setting on foot of the decasyllabic couplet, which he began well in the _Legend of Good Women_, but carried on much better in the _Canterbury Tales_. Not half of his actual achievement here, and a very much smaller part of his promise and stimulus for the future, can be perceived by those who limit him to the decasyllable as such by devices of elision and syncope; still less by those who would have his varieties of line exactly to represent variations of the French decasyllable. The former proceeding is inadequate and defacing; the latter practically impossible, except as a bare and barren matter of arithmetic. You cannot imitate the prosodic effect of one language in another, even though you take the exact number of syllables and (as far as you can) divide the words, arrange the accents, etc., with the most slavish copying. The result will laugh at you prosodically; and while it is very unlikely to give you anything similar, it is nearly certain to give you something quite different.[70]