Read it through once

The length, the province, and the tone, being thus determined, I betook myself to ordinary induction, with the view of obtaining some artistic piquancy which might serve me as a keynote in the construction of the poem—some pivot upon which the whole structure might turn. In carefully thinking over all the usual artistic effects—or more properly points, in the theatrical sense—I did not fail to perceive immediately that no one had been so universally employed as that of the refrain. The universality of its employment sufficed to assure me of its intrinsic value, and spared me the necessity of submitting it to analysis. I considered it, however, with regard to its susceptibility of improvement, and soon saw it to be in a primitive condition. As commonly used, the refrain, or burden, not only is limited to lyric verse, but depends for its impression upon the force of monotone—both in sound and thought. The pleasure is deduced solely from the sense of identity—of repetition. I resolved to diversify, and so heighten, the effect, by adhering, in general, to the monotone of sound, while I continually varied that of thought: that is to say, I determined to produce continuously novel effects, by the variation of the application of the refrain—the refrain itself remaining, for the most part, unvaried.