This isn't a novel, but it has all the elements of a great puzzle. How to Draw a Straight Line is the text of a lecture Kempe gave in 1877. The central question is deceptively simple: how can you build a machine, using only hinged rods, that forces a pencil to move in an absolutely straight path? For centuries, this was a huge headache for engineers and designers who needed precision.

The Story

Kempe walks you through the history of this mechanical quest. He starts with basic concepts and then introduces you to the cast of "characters": famous linkages like the Peaucellier-Lipkin cell and Hart's inversor. With clear diagrams and logical steps, he explains how these clever arrangements of rods and pivots perform their geometric magic, converting circular motion into straight-line motion. It's the story of a problem and its elegant solutions.

Why You Should Read It

What I love is how it makes you see the world differently. You start noticing linkages everywhere—in car suspensions, folding gates, robot arms. Kempe’s writing is clear and enthusiastic; he’s not just presenting facts, he’s sharing a cool trick. It demystifies a piece of engineering history and shows that deep mathematical ideas can have beautifully physical, almost artistic, solutions.

Final Verdict

Perfect for curious minds who enjoy puzzles, makers, tinkerers, or anyone with a soft spot for Victorian science. It’s a quick, satisfying read that connects the dots between pure math and the physical machines that shaped our world. You don't need to be an engineer to get it, just a bit of patience and a sense of wonder.