On the History of Gunter's Scale and the Slide Rule During the Seventeenth Century

Before computers, there were hands and sticks and logarithms. This is the story of the instruments that first made calculation portable: Gunter's scale and the slide rule. Florian Cajori, the preeminent historian of mathematics, traces the bitter disputes over who invented what, the rivalries between mathematicians like William Oughtred, Edmund Wingate, and Richard Delamain, and how these wooden and ivory devices transformed engineering, astronomy, and navigation in the seventeenth century. The book reveals not just technical specifications but the human drama of early scientific competition, where reputation and priority sparked decades of acrimony. Cajori writes with the precision of a scholar who spent decades in archives, yet he never loses sight of the larger significance: these humble scales and rules were the first tools to compress complex computations into motions a human hand could perform. For anyone curious about where our digital age truly began, this is the origin story.