This thesis considers two aspects of the literary style of Sir Thomas Browne. The first four chapters examine the novelty and creativity of his diction, and chapters five to eight describe and interpret the rhetorical features inherent in his sentence-structures. A final chapter summarises the significance of my findings. Chapter one surveys the history of critical opinion and comment upon Browne's choice of words. Chapter two assesses the degree to which it is possible to define innovation in English vocabulary by reference to lexicographical techniques. Chapter three, in three parts, considers the historical background to innovative diction in the seventeenth century, especially as it is evident in learned and scientific writings. The fourth chapter is a detailed examination of the presence, function and impact of word-coinage in Religio Medici, Pseudodoxia Epidemica and The Garden of Cyrus. Chapter five provides a summary of the persuasive aspects of rhetoric in Browne's prose. Chapter six examines his use and omission of personal pronouns, as indicators of feeling and belief. Chapters seven and eight consider the processes of argument in Pseudodoxia Epidemical and both the direct and indirect means by which Browne registers the degrees of his convictions, beliefs and opinions. A brief concluding chapter asserts the value of Browne's style in discourses designed to persuade, as well as in those which provoke the imagination. A substantial appendix registers, alphabetically, those words for which there is evidence that Browne was their first literary user. Further appendices provide data relating to these coinages, and analyse their presence in both Browne's works and in those of other contemporary writers.