"What he learned from Dryden," Mr. Courthope says in another place, "was the art of expressing the social and conversational idiom of the language in a metrical form. His conception of metrical harmony was, however, altogether different from his professed master's, and rather resembled that of Sandys, whose translation of Ovid's Metamorphoses he told Spence he had read when very young, and with the greatest delight. He explains the system in a letter to Cromwell, dated November 25, 1710.
"'(1) As to the hiatus, it is certainly to be avoided as often as possible; but on the other hand, since the reason of it is only for the sake of the numbers, so if, to avoid it, we incur another fault against their smoothness, methinks the very end of that nicety is destroyed....
"'(2) I would except against the use of all expletives in verse, as do before verbs plural, or even the frequent use of did or does to change the termination of the rhyme....
"'(3) Monosyllable lines, unless very artfully managed, are stiff, languishing, and hard.
"'(4) The repeating the same rhymes within four or six lines of each other, which tire the ear with too much of the like sound.
"'(5) The too frequent use of alexandrines, which are never graceful, but where there is some majesty added to the verse by them, or when there cannot be found a word in them but what is absolutely needful.
"'(6) Every nice ear must, I believe, have observed that in any smooth English verse of ten syllables, there is naturally a pause either at the fourth, fifth, or sixth syllables.... Now I fancy that, to preserve an exact harmony and variety, none of these pauses should be continued above three lines together, without the interposition of another; else it will be apt to weary the ear with one continued tone.'"
(Ibid. pp. 20, 21.)
Here are implied all the characteristics of the Popean couplet. The cesura is to vary, but not from a fundamentally medial position. The avoidance of enjambement is not mentioned, doubtless because it is assumed as an essential of couplets professing any degree of correctness.
Mr. Andrew Lang protests against the monotony of the verse of Pope's Iliad in some lines which cleverly adopt the same sort of measure: