Originally published in 1951, this book explores the nature of literary influence, and its part in literary creation, as found at work in some aspects of French poetry after Baudelaire. Part I contains an essay on Swedenborg and Baudelaire, an essay on Edgar Allan Poe, Baudelaire and Mallarné, a third on the 'imposing but frequently miscalculated effects' of Baudelaire's discovery of Poe and a fourth on Whitman and the Symbolists. Part II is concerned with prosody, and contains four essays entitled 'From poetic prose to the prose-poem'; 'the development of the vers libéré; 'the first theory of vers libre'; 'Whitman and the origins of the vers libre'. With these eight essays are reprinted the vivid accounts of personal interviews which the author had as a young man more than thirty years before publication - when he first began to investigate the problems discussed in these essays - with the post-Symbolist poets.