A collection of essays of enduring interest in the history of science by Charles Coulston Gillispie, Dayton-Stockton Professor of History of Science, Emeritus, at Princeton University. He founded the undergraduate program in the History of Science at Princeton in 1956 and continues to work with students as they pursue their scientific studies. The pieces are arranged not chronologically but in broad topical categories: Early Papers, French Science, General Topics, Historians and Historians of Science, and Science and Society. Gillispie has provided introductory remarks in order to situate them in the circumstances wherein they were written.