“A narrow Fellow in the Grass” is loosely based on what is called “common meter.” Common meter is the same sort of pattern you’d find in Protestant Christian hymns. What's that pattern look like? Well, first off, it alternates between lines of iambic tetrameter and iambic trimeter. How's that, you say? Well, an iamb is a pair of syllables in which the first is stressed and the second is unstressed. It makes a sound like da DUM (say the word "allow" and you'll hear an iamb). Iambic tetrameter, then, tells us that a line has four iambs in it ("tetra" means four), where iambic trimeter is a line of three iambs.
“Amazing Grace” is the most famous hymn in common meter, so let's check out how this rhythm sounds in action:
Amazing grace how sweet the sound
That saved a wretch like me
I once was lost but now am found
Was blind but now I see
If you go back and read that out loud, you should hear four da DUM's in likes 1 and 3 (that's iambic tetrameter) and three da DUM's in lines 2 and 4.
Notice, too, the rhyme scheme here. Lines 1 and 3 rhyme, as do lines 2 and 4, so the rhyme scheme would be ABAB, where A represents the end rhyme in lines 1 and 3, and B represents the end rhyme in 2 and 4.
Okay, so any questions about the common meter? Good. Emily Dickinson probably picked this up from her family, since they belonged to a Calvinist community. Only, much of her poetry (this one included) uses something slightly different, called ballad meter. Ballad meter is different from common meter in that only the even numbered lines have to rhyme. So, instead of a rhyme scheme of ABAB, we'd get a scheme of ABCB (lines 1 and 3 don't rhyme).
Ballad meter, like common meter, still means alternating lines of iambic tetrameter and trimeter, though. For example:
The Grass divides as with a Comb--
A spotted shaft is seen-- (5-6)
You should hear four, then three dum DA's in those lines, indicating the rhythm of the ballad meter. Still, this is not iron-clad for the poem. There are lines that don't neatly follow the pattern, namely after the second stanza. And this consideration leads us to…
Why would Dickinson choose this format to deliver her poetry? Well, one answer has to do with her religious upbringing and familiarity with hymns, as we've already mentioned. Still, there's also something a bit… disquieting about putting these deceptively tricky thoughts in what normally amounts to a sing-songy pattern. The regular rhyme and rhythm tends to lull the reader to sleep a bit. It's easy to gloss over the really detailed eye of Dickinson in the imagery and personification at work in her poem.
We think, though, that this was part of the point. Notice how, instead of the regular 8 syllables in lines 1 and 3, from stanza three on, the first and third lines of each stanza only contain 7? What's going on here? Is this a coincidence?
Nay, Shmoopers, we submit to you that Dickinson knew precisely what she was doing. In a poem that plays with the line between reality and imagination (it is a snake or a whip?), this metrical shift happens on purpose. Just as the reader is kept on his toes about the nature of the speaker, the nature of the snake—heck, the nature of reality itself, the meter of the poem also changes to subtly indicate that not everything is as expected.