ca. 1920's-1940's
Medical Museum Collection, Box 74
A slide rule in a tan leather case, measuring 28 x 3.5 x 1 cm. The wooden rule has a clear plastic sliding plate. It was donated by Laurence Selling, M.D., in November 1964, and is in excellent condition.
Digital photograph of a wooden slide rule and its leather carrying case, both set on a gray counter. A ruler has been placed in the foreground for size comparison.