The sound device which is used in the above lines from “Kubla Khan” by Samuel Taylor Coleridge to emphasize the amazement the speaker expects people to feel if he is able to build a dome of air is:
the assonance between “close” and “holy”
Explanation:
Assonance is a figure of speech in which the sound of the words or the syllables has a resemblance with each other. The resemblance of a vowel sound is said to be assonance.