From The Dark Tower

A sonnet is a poem consisting of 14 lines. This sonnet follows the Petrarchan sonnet form, named after the 14th-century Italian poet Petrarch. The Petrarchan sonnet begins with an octave (eight lines) in which a situation, problem, or burden is presented. This is followed by a sestet (six lines) that resolves, or alleviates, the problem and restores a hope or a vision. Cullen follows this format, since the negations and privations that make up the octave give way to positive affirmations in the sestet.

The meter of the sonnet is iambic pentameter. An iamb is a poetic foot consisting of an unstressed syllable followed by a stressed syllable. It is the most common meter in English poetry. This sonnet has only a few variations on the iambic rhythm. Thus, the first two lines are regular iambic pentameter: “We shall not always plant while others reap / the golden increment of bursting fruit.” Only once does Cullen vary this rhythm, and that is in the first foot of Line 10: “White stars.” This is a spondee, that is, a foot in which both syllables are stressed.