The first, and most well-known, sonnet of Philip Sydney's sonnet sequence, Astrophil and Stella, uses many different literary devices. The most obvious is meter. The poem is written in iambic hexameter. It is also uses the device of rhyme, specifically the form of an English sonnet, rhymed abab abab cdcdee, with the interesting pattern of assonance between the a and d and b and c rhymes.
It uses anadiplosis (cause her read, reading might), and gradatio (Pleasure might cause her read, reading might make her know, Knowledge might pity win, and pity grace obtain). It uses polyptoton (loving … love; know … knowledge; read … reading). It also uses alliteration in several places (fresh and fruitful; burned brain).