What are the figures of speech used in "To Autumn" written by John Keats?

Keats's "To Autumn" uses many literary devices, but
several stand out as contributing majorly to the structure of the poem.  The first of
these literary devices is apostrophe.  Apostrophe is when the speaker of a poem
addresses, or speaks to, something that can't speak back.  In this poem, Keats's speaker
is addressing autumn when he asks, "Who hath not seen thee oft amid thy store?" (line
12).

Another literary device that Keats uses in this poem
is personification.  Just as he speaks to autumn, he also personifies (or describes
something as if it were a person) autumn as a worker in a granary, sleeping on the floor
because of the heavy drowsiness that Keats associates with the season in the first
stanza.

A final literary device, and perhaps the most
pervasive in the poem, is imagery.  Keats employs visual imagery in the first stanza, in
which he describes the "swell[ed]" gourd and the "plump...hazel shells" (7).  In the
third stanza, the imagery becomes auditory, as Keats describes the "music" of autumn
(23), such as the "twitter[ing]" swallows and the "wailful choir" of gnats (33,
27).