In verse one can take any damn constant one likes, one can alliterate, or assone, or rhyme, or quant, or smack, only one MUST leave the other elements irregular.
Ezra PoundHaie! Haie! These were the swift to harry; These the keen-scented; These were the souls of blood. Slow on the leash, pallid the leash-men!
Ezra Pound