Answer:
And much it griev’d my heart to think
What man has made of man.
Alliteration refers to the repetition of identical initial consonant sounds in closely associated syllables within a particular group of words. Alliteration is also known as head rhyme, or initial rhyme, and it is one of the most commonly used devices in poetry. In this case, these lines use alliteration in the words "man," "made" and "man."