Contributions to the History of Science: Parts I and II is a scholarly work encompassing two significant historical scientific texts, translated and contextualized by notable academics. Part I features Robert of Chester’s Latin translation of the Algebra of Al-Khowarizmi, a pivotal 12th-century Arabic mathematical treatise. Louis C. Karpinski provides a modern translation from the Latin, an insightful introduction, and a glossary, enhancing appreciation of Arab contributions to mathematics. Part II includes an English translation of Nicolaus Steno’s Prodromus, detailing his groundbreaking 17th-century work on crystallography and geology. John G. Winter enriches this translation with an introduction, explanatory notes, and biographies, complemented by Professor W. H. Hobbs' foreword, which underscores Steno’s pioneering observational methods and their alignment with modern scientific principles. Together, these works offer profound insights into the evolution of scientific thought and methodology.