Simplify the following text for a Grade 10 native English-speaking person.
Original: He is known to posterity primarily for his collection of poems titled Poems on Various Subjects , whereto is Prefixed a Short Essay on the Structure of English Verse , published in 1765 .
Simplified: He is known mostly for his collection of poems called Poems on Various Subjects , whereto is Prefixed a Short Essay on the Structure of English Verse , published in 1765 .