The slide rule : a practical manual

First published in the early twentieth century, this practical guide turns the slide rule—a once‑essential calculating tool—into an accessible companion for engineers, technicians, and curious hobbyists. The author walks listeners through the mathematical foundations of logarithms, then shows how those ideas become the sliding scales on the instrument. Even without formal training in logarithms, readers quickly learn to perform multiplication, division, roots, and basic trigonometric work with confidence.

The manual’s second half expands into specialty rules, covering topics such as gear‑cutting calculations, log‑log scales, and circular calculators—tools that once powered shipyards and machine shops. Practical examples are interwoven with tips on setting up the cursor, reading gauge points, and checking accuracy, giving listeners a hands‑on feel for each operation. By the end of the session, the audience will not only understand how the slide rule works, but also how to apply it to everyday engineering problems, preserving a piece of mathematical heritage for modern minds.