Sir Isaac Newton wanted to better understand optics, so one day in the 1660s -- don't try this at home, folks -- he took a small, flat probe, slid it into his eye socket, and fiddled around. In the midst of his wiggling he glimpsed, among other things, "a great broade blewish darke circle" and "several white darke & coloured circles." At first glance, that's hardly the sort of data that seems worth risking an eyeball for, but Newton was in fact onto something: It helped him discern the nature of light and color, though eventually he employed prisms and pinholes instead of his own skull.

To be clear, Newton's self-experimenting isn't one of the great moments George Johnson was thinking of when he titled his book "The Ten Most Beautiful Experiments." But Newton's moment of obsession (and questionable judgment) is included in Johnson's unusual and engaging book for a reason: the better to stress the idea that scientific research is often a clumsy business performed by imperfect, illogical human beings. Some of the most charming moments in the book, in fact, turn on very personal moments in scientists' lives. Michael Faraday, for instance, seemed pulled out of his professional doldrums by the flirtations of Lord Byron's daughter, and soon after he was spurred to locate the connection between light, electricity and magnetism; when Galileo was clocking a ball's rate of acceleration, he wasn't using a sophisticated timing device, but more likely was tapping out a rhythm and humming a tune.

That plays into Johnson's definition of a "beautiful" experiment: one in which the "logical simplicity of the apparatus, like the logical simplicity of the analysis, seem as pure and inevitable as the lines of a Greek statue." Simplicity is a relative term here. Robert Millikan assembled a complex contraption to discern the nature of electrons. (Johnson knows just how complex; he tried to replicate it, with limited success.) And A.A. Michelson assembled a very carefully calibrated array of mirrors while calculating the speed of light. But now that we're in an era of science-by-committee, Johnson's book harks back to a simpler time: It's a tribute to the lone scholar, arriving at solutions in rigorous isolation.

Johnson's book is slim, and he clearly strived to craft an unfussy, jargon-free study of these men. (And they are all men, which he acknowledges in a brief afterword.) None of the individual chapters cracks 20 pages of illustrated text, which sometimes makes for a compressed, too-quick trip through the material; reading the book can feel like cruising through a science museum in a speedy golf cart. But Johnson is an experienced science writer with a knack for making biology and physics clear, and for finding the humanizing details in this world, as when he describes William Harvey bandaging an arm to show how blood circulates, or Ivan Pavlov connecting his famous dogs' behavior to a series of notes.

The stories also reveal some of the absurd notions that many scientists once carried in their heads: that combustion was once fueled not by oxygen but by a substance called phlogiston, and that planetary motion was slowed by "aether winds." But, Johnson, reminds us, we're in an age of absurdity now, too, proposing "dark matter" and "dark energy" to explain complex cosmic phenomena. The history of Johnson's great experimenters is over before World War II, but a universe of great unknowns remains.

Mark Athitakis is the arts editor of Washington City Paper. He blogs at americanfiction.wordpress.com.