You're not alone if you find yourself a bit stumped by Dickinson's choice of meter and rhyme in most of her poems. To this day, scholars are still fighting over what to call her common but often not-so-common choices. Her unusual rhymes are often the biggest parts of the debate.
Dickinson tended to write a lot of her poetry in a style called "common measure." The means that the meter alternates between iambic tetrameter and iambic trimeter. An iamb is just a pair of syllables where the emphasis comes on the first (daDUM). (Say "allow" out loud to hear an iamb.) Iambic tetrameter, then, means that we've got four (tetra- means four) sets of iambs in a line; iambic trimeter means that we have three sets. So, the first and second line of a poem with common measure would sound like:
daDUM daDUM daDUM daDUM
daDUM daDUM daDUM
We get an example in Dickinson's famous poem "Because I could not stop for Death":
Because I could not stop for Death—
He kindly stopped for me—
Hear that regular pattern? Now read "There's a certain Slant of light" out loud. Go ahead. We'll wait right here. Notice anything? If you're not hearing that regular common measure, congratulations! Neither are we. This poem is far less regular, more halting in its rhythm. Just consider the first two lines:
There's a certain Slant of light,
Instead of iambs, what we get here are a lot of trochees, which are syllable pair where the stress falls on the first syllable, not the second: DUMda ("certain," "Slant of," "Winter"). These guys are pretty much the opposite of iambs, so what gives? Well, it could be the Dickinson is deliberately playing with the set patterns of common measure, in some cases inverting those rhythmic rules altogether. We've already told you this was no prim and proper poet, but could her sonic rebellion have another point?
We're glad we asked…ourselves. One thing that this trochee madness accomplishes is a kind of lurching, halting beat that never feels quite regular or safe. Instead, we get a lot of fits and starts, jabs and lulls—all of which mimic the disharmony that the speaker is describing. Even right down to the rhythm, something is very off here.
The same can be said for the rhyme scheme. Common measure poems usually follow the pattern of ABCB, with different rhymes for each stanza. In this case, we get "afternoon" and "tunes," "scar" and "are," and "despair" and "air." The tricky thing about Dickinson's poems is that we often see a few slant rhymes thrown in there. For instance, lines 1 and 3 have a bit of a rhyme in their ending consonant sounds: "light" and "heft." We can't say this is an exact rhyme, but there is some consonance jiving in those lines.
Perhaps this kind of nearly-there slipperiness with form and meter is part of the reason why Dickinson is one of the most talked about poets of all time. So many years later, folks are still scratching their heads over her rebellious ways. Those dashes she uses are also a hot topic. We'll talk more about them in our "Sound Check" section, but for now, as far as form is concerned, those dashes help to create a mood of dissonance and cohesion all at the same time. In other words, it looks put together and not so put together simultaneously, which fits rather well with the whole paradoxical idea of "Heavenly Hurt" and that pesky, off-putting "Slant of light."