This book delivers an in-depth analysis of Hercule Florence, who is virtually unknown despite being among the world's photographic pioneers. Based on the texts of various manuscripts, letters, diaries, notes, and advertisements, this book answers numerous questions surrounding Florence's work, including the materials, methods, and techniques he employed and why it took more than a century for his discovery to come to light. Kossoy's groundbreaking research establishes Florence's use of "photographie" to describe the product of his experiments, half a decade before Sir John Herschel recommended "photography" to Henry Fox Talbot. This book aims to change the fact that despite its cultural and historical importance, Florence's photographic breakthrough remains largely unknown in the English-speaking world.