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Napier’s Bones: The Calculating Rods That Multiplied Before Machines DidIn 1617, a dying Scottish laird described a handful of ivory rods in his final book. Those rods became the pocket calculator Europe carried for the next two centuries.

What Is Mathematics Good For?Nobody loves music because it is useful. Nobody plays football because sport is good for you. A manifesto on why mathematics is good for nothing — and, for that very reason, good for everything.

Here’s Looking at Euclid: Helen Friel Folds Byrne’s Proofs into PaperIn 1847 Oliver Byrne turned Euclid’s proofs into coloured figures. A hundred and sixty-five years later, paper engineer Helen Friel lifted those same figures off the page and folded them into three dimensions.

Marie Curie's Radioactive NotebooksMarie Curie's laboratory notebooks are still radioactive a hundred and thirty years later. The National Library of France keeps them in lead-lined boxes. To turn the pages, you sign a waiver first.

The House That Calculus Paid ForWhat does the author of the world's best-selling calculus textbook do with the money? He builds a five-storey concert hall into the slope of a Toronto ravine, with door handles cast in the shape of the integral sign, and lives inside it.

James Garfield's Proof of the Pythagorean TheoremIn 1876, a congressman from Ohio proved a 2,400-year-old theorem in a hallway of the Capitol using nothing but a trapezoid. Five years later he was president.