A representative examination of the first three stanzas of "To a Skylark" by Percy Byshee Shelley shows that the poem has an abundance of figures of speech. Figures of speech come in many forms and are words or phrases that have either a figurative nonliteral meaning that enhances the concepts and images of the text along with having a literal meaning that fits the context of the narrative or word patterns that have an affect on the conceptual meaning and literal text through the word patterns.
Figures of speech are categorized under literary devices designated by the term trope. Schemes, which are figures of speech that similarly enhance meaning but are not tropes with nonliteral meanings, are also used by Shelley in "To a Skylark," but shemes deal with patterns of words, not literal and nonliteral meanings of words. For instance the type of word scheme called antimetabole occurs in the last line of the second stanza, which says,: "And singing still dost soar, and soaring ever singest." Note how the pattern of words appears in reverse order in the two halves of the line: descending to the middle of the line is, in a paraphrase, singing still soars, while ascending away from the middle is soaring still sings.
The poem opens with the trope figure of speech called an apostrophe in which an object or a nonhuman entity--in this case, the skylark--is spoken to as though it were a living human [apostrophes are also addressed to people who are absent or deceased]: "Hail to thee, blithe Spirit!" Don't be confused by the apostrophe being addressed in a metaphor to "Spirit!" The skylark is still being addressed as though it were a human being. There follows in the fourth line of the opening stanza a synecdoche in "thy full heart," wherein a physical object (i.e., "heart") is used to represent the whole (i.e., skylark). A metonymy occurs in the fourth line of the second stanza: "The blue deep thou wingest." The "blue deep" is a suggestive specific object that represents a larger whole or general concept: In this case the metonymy of "blue deep" is standing for the Earth's physical atmosphere, or sky.
There are two similes, "Like a cloud of fire"--being also a Biblical allusion to the Hebrew tribe wandering in the desert after fleeing Egypt--and "Like an unbodied joy" in stanzas two and three, respectively. There is also one metaphor opening stanza three, "golden lightening," which paints a picture, an image, of rays from the sunset's "sunken sun" splaying out in golden rays to the clouds above and around.