“The Measure of All Things: The Seven-Year Odyssey and Hidden Error That Transformed the World”, by Ken Alder

448 pages, Free Press, ISBN-13: 978-0743216753

In The Measure of All Things: The Seven-Year Odyssey and Hidden Error That Transformed the World, Ken Alder has undertaken to find every bit of drama, adventure and intrigue he can find surrounding the invention of…the metric system (I know, right?). I mean, really, how interesting can a discussion on meters vs. feet be? Ah, you’d be surprised, Dear Reader, as Alder’s comprehensive knowledge and smooth writing bring interest and liveliness to what could have been a very dull topic. Central to his tale is the complicated personalities of the two 18^th Century Frenchmen – Jean Baptiste Joseph, Chevalier Delambre, and Pierre François André Méchain – who set out to define the proper length of the meter, their intention being to establish a new, standardized system of measurement in the belief that drafting measurements from the Earth itself would give each citizen of the world the confidence that at least one aspect of life had reason and permanence (not that many Frenchmen noticed, as they were just then in open revolt against the king – mon Dieu!). In June 1792 Delambre headed north from Paris while his elder colleague Méchain headed south in order to triangulate a meridian across France, to be used to extrapolate 1/10,000,000^th of the distance from the North Pole to the Equator. As the book’s title informs us, this little field trip took seven years, during which time France underwent a bloody ideological class uprising, which then turned into a savage civil war, which then culminated in the dictatorship of Napoleon Bonaparte.

As the book’s title also informs us, the number was wrong, as Méchain bungled his data and then covered up his mistake by adjusting the figures to more closely match the “provisional meter” that the French Royal Academy had already adopted. Throughout the book, Alder lays out the folly of the expedition, but with a sympathy born of one who knows how the tale ends. You see, neither Delambre or Méchain – or any other astronomer of the time, for that matter – knew how misshapen and imperfect the planet actually is…which means they would have been better off just making up a number. As it happened, Méchain’s inability to get the results he wanted drove him to an early grave, while Delambre’s belated discovery of his partner’s deceit turned the younger scientist more philosophical and launched an era in which accounting for error became an important part of scientific study. Alder clearly admires Delambre and Méchain for their contributions to modern science, however inadvertent. He also writes warmly about their era, when number-crunchers were hailed as savants and had the ear of kings and commoners alike, and when science involved strapping on hiking boots and heading into the wild to refine the common understanding.