Newton's Opticks is the most influential optical and experimental work of the eighteenth century. This final volume of The Optical Papers of Isaac Newton contains manuscripts that document the evolution of the Opticks through its three principal published editions. It shows how Newton constructed the book that for over a century was the leading treatise on optics, a fecund source of natural philosophical speculations, and which is now considered a classic of science. The volume opens with the manuscript of the first edition (1704) and the first draft of the Opticks in Latin, which he soon abandoned for English. This is followed by the manuscripts of the queries that Newton added to the Latin translation in 1706 and the second English edition in 1717. Other, shorter manuscripts are included, as are copious notes and commentary, making this a valuable resource for historians and philosophers of science, and historians of philosophy.