Before about 1950, a computer was a person, not an electronic machine. Yet commerce, industry, and science proceeded, and even thrived, because computers were able to use a variety of mechanical calculating gadgets; some simple, some quite ingenious and complex.

In this course we explore the computational techniques used before the invention of integrated circuits and handheld electronic calculators. Among these are slide rules, planimeters (for measuring areas), integrators (for measuring moments of areas), digital adding machines, nomograms, and other graphical techniques. Examples of other instruments will include harmonic analyzers that were developed to interpret cyclical phenomena such as ocean tides, and mechanical analog computers for the fire control of naval gunnery. We will touch on celestial navigation, because it was the greatest computational challenge of its day, and the closely related fields of surveying and geodesy. We will also look at cryptography, whose computational requirements helped to propel us into the electronic age.

Each class meeting will be a lecture, usually with hands-on exposure to antique and period calculating instruments.