John Dryden 
The Works of John Dryden, Volume XVII [PDF ebook] 
Prose, 1668-1691: An essay of Dramatick Poesie and Shorter Works

This collection of prose writing from the pen of Dryden dates from 1668 to 1691, and contains work that the editors describe as ‘a sampler of Dryden as biographer-historian, political commentator, religious controversialist, literary polemicist, literary theorist, and practical critic. Among the works contained here is his ‘Essay of Dramatick Poesie.’