Dickinson's poems, for the most part, are written in what's referred to as "ballad stanza," which means that they have a singsong, hymn-like quality. It's no coincidence that you can sing pretty much any Dickinson poem to the tune of "Amazing Grace" – they're written in this same meter, like a lot of other songs. Technically ballad stanza is quatrains of alternating iambic tetrameter and trimeter in an ABCB rhyme scheme.
What does this mean? Well, first of all, let's tackle the word "quatrain." That just means a stanza made up of four lines. You probably noticed that "There is no Frigate like a Book" has two quatrains.
Moving right along, let's talk about iambic meter. This poem has the rhythmic, da-DUM da-DUM da-DUM feeling of an iambic meter. An "iamb," a popular kind of metrical "foot" (or unit) is made up of two syllables, one unstressed (da), and the other stressed (DUM). It might help to think of the clever reference to "prancing Poetry" in line 4, and imagine a horse briskly trotting along to get a feel for this meter. When you put several iambs in a row, you get that two-step rhythm that makes Dickinson so fun and easy to read aloud.
Ballad stanza has alternating lines of four and three iambs, thus the names "iambic tetrameter" (tetra = four, like Tetris) and "iambic trimeter" (tri = three, like tricycle). Make sense? No? Yes? Maybe? To be safe, let's try and read aloud together – the bold, italicized syllables are the stressed ones. We're also separating the iambs with slashes so you can really see the three- and four-syllable lines. Try to really exaggerate the difference between unstressed and stressed syllables to feel the even beat of these lines:
There is | no Frig|-ate like | a Book
To take | us Lands | a-way
Get it? As for rhyme, you can easily pick out the rhyme pattern here, even when it's a little wonky. The second and fourth lines of each stanza rhymes (ABCB DEFE). This works out beautifully in the second stanza, where "Toll" and "soul" match up perfectly, but in the first stanza – "away" and "Poetry" – we have what's called a slant or sight rhyme. That is, we can see that the two words "rhyme" because of their common ending, but it doesn't sound exactly right when you read it out loud. So, those of us who were embarrassedly trying to make "Poetry" sounds like "away" ("Um, Po-e-tray?") can breathe a sigh of relief. This slant rhyme may seem weird, but it's most definitely not an accident. Rather, it's one of Dickinson's trademarks, and the common occurrence of slant rhymes in her poems keeps them from being dully consistent and sing-songy in form (in our humble opinion).