One Form of Electricity

By PETER DIZIKES
Published: April 13, 2008
Beauty is truth, Keats declared, and truth beauty. Many prominent scientists have wished a version of this famous equation described their own work. The British quantum theorist Paul Dirac, for one, called his career “a search for pretty mathematics.” Most scientific aesthetes gaze fondly upon equations or arrangements of facts. A few, like the science writer George Johnson, also see beauty in the act of research. Johnson’s new book, “The Ten Most Beautiful Experiments,” is an appealing account of important scientific discoveries to which a variation of Keats applies: occasionally, beauty yields truth.

Johnson’s list is eclectic and his outlook romantic. “Science in the 21st century has become industrialized,” he states, with experiments “carried out by research teams that have grown to the size of corporations.” By contrast, Johnson (a longtime contributor to The New York Times) favors artisans of the laboratory, chronicling “those rare moments when, using the materials at hand, a curious soul figured out a way to pose a question to the universe and persisted until it replied.”

His selections include the canonical and the overlooked. The first chapter describes Galileo’s studying motion by rolling balls down an incline, often considered the founding experiment of modern science. Another chapter recounts Isaac Newton’s using prisms to grasp the nature of color. But Johnson also brings to life less familiar figures like Luigi Galvani, who illuminated the nature of electricity; Albert Michelson, who (with Edward Morley) determined the constant speed of light; and — a particularly inspired choice — Ivan Pavlov, whose famous dog experiments advanced physiology and neurology.

Johnson has a good feel for detail — Pavlov, in fact, rarely used a bell — and an easy touch with larger concepts. The vexing, counterintuitive Michelson-Morley result showed that light always appears to travel at the same rate, regardless of our relative movement or the mythical “aether” once thought to slow it down. As part of Einstein’s theory of special relativity, Johnson writes, this principle helped make clear that “there is no fixed backdrop of space, or even of time.” Instead, the speed of light is “the one true standard.”

Historians have wondered how much Einstein knew about the Michelson-Morley experiment, or if he reached the same conclusion independently. Johnson bypasses such discussions, although he could have noted this one (or explained why Michelson is more significant than Morley). Instead, he quickly sets the scene of each discovery and explores how each scientist sorted out a rich, messy mixture of evidence and theory — no fixed formulas here about how science progresses.

Johnson’s best chapter describes the ad hoc scientific duel in the 1790s over the nature of electricity between Galvani, who had accidentally discovered “animal electricity” in dismembered frogs (don’t ask), and a skeptical Alessandro Volta, who thought Galvani’s metal tools had generated the effect. Neither was entirely right. Their debate, however, helped prove that there is only one form of electricity (not many, as some thought), and that it flows through life, too.

Johnson’s lively book nicely evokes the lost world of the tabletop experiment. But are all remaining advances really beyond the reach of individual hands and minds, as he supposes? Might we still attribute major ideas to ingenious individuals, even if the ideas are tested by teams?

Certainly, Johnson is entitled to his nostalgia. Still, if lone scientists rarely push knowledge forward today, they rarely impede it, either. Consider William Thomson, Lord Kelvin, who appears here in a chapter on James Joule’s heat experiments. For all he accomplished, Kelvin later dismissed geological evidence about the Earth’s age, using his authority in thermodynamics to insist our planet was much younger than evolutionists like Charles Darwin and T. H. Huxley supposed. Kelvin’s conclusions were wrong, but it took decades to overturn his views. Sometimes, less individual influence is a good thing.

One other question lingers: What makes a scientific experiment beautiful? Johnson favors simplicity — not just clean, artful experiments, but those that let us replace convoluted theories with simple explanations. Galileo applied uniform mathematics to the motion of all objects, contradicting Aristotle’s idea that heavier objects fall at faster rates. William Harvey showed that one form of blood circulates throughout the body, not two. Newton proved colors are refracted light beams, not Descartes’s complex “spinning globules of aether.”

Historically, few people seeking beauty in science have displayed a baroque sensibility. The traditional aesthetic is classical, invoking the simplicity and symmetry of revealed forms — whether they have been revealed on a cluttered lab bench or through elegantly spare theorizing.

Indeed, the notion that scientific thinking is beautiful enjoyed a neoclassical revival, following the spread of Newton’s work in the 18th century. When Johnson says his 10 scientists found “an unknown piece” of the universal “scaffolding,” the architectural metaphor is telling. In this view, scientists who have sized up the world’s complexity and extracted lucid explanations are a bit like the engineers of ancient Greece or Rome who studied piles of stones and formulated basic building principles. We judge their work based on both form and function.

If Johnson’s aesthetic sense is conventional, however, his vision is broad. This tidy book finds beauty throughout science — even among dead frogs and drooling dogs.