Chatham (referring to William Pitt, 1st Earl of Chatham and Prime Minister of Great Britain from 1766 to 1768)
The aforementioned clues form an acrostic revealing the name of a town.
The answer can be found in An Answer to the Rebus, by the Author of these POEMS.
A Rebus, by I.B.
quail, unicorn, emerald, Boston, Euphorbus, Chatham (referring to William Pitt, 1st Earl of Chatham and Prime Minister of Great Britain from 1766 to 1768).
Author/Artist: Wheatley, Phillis
Publisher:Bell, Archibald, [Publisher, London]; Wheatley, John d. 1778, associated name; printed for A. Bell, bookseller, Aldgate, and sold by Messrs. Cox and Berry, King-Street, Boston, M DCC LXXIII.
Description: Acrostic rebus poem on p. 123 of Poems on various subjects, religious and moral / by Phillis Wheatley, Negro servant to Mr. John Wheatley, of Boston, in New England.
Repository: University of Illinois at Urbana-Champaign