Lone Questioners of the Universe
Celebration of Solitary Science in ‘10 Most Beautiful Experiments'
Nov 7, 2009
That battery-making experiment in your seventh grade science class might not have been especially exciting. Build a pile of dissimilar metal discs – say, half of them copper and half of them zinc. Between each disc, place a piece of cardboard soaked in salt water. Build a high enough tower, and touching it can give you a mild shock.
Just over two hundred years ago, that same project became a turning point in science. The Italian scientist Alessandro Volta published a paper in 1800: “On the Electricity Excited by the Mere Contact of Conducting Substances of Different Kinds.” He had invented the battery.
Now batteries of all voltages, shapes and sizes power up every gizmo you own, from laptop computers to hybrid cars. But they began with an idea, and then with an experiment to test that idea – and that is the ongoing adventure of science, including your own seventh-grade experience as a scientist.
George Johnson (he also writes and edits the online Santa Fe, New Mexico Review) is among the best of guides on any scientific adventure. He is especially engaging in his depictions of “The Ten Most Beautiful Experiments” (Alfred A. Knopf, New York, April 2008, ISBN 1400041015).
He has a focused goal: examining experiments from era to era when scientists essentially worked alone, before the coming of “industrialized” science, as he terms modern projects with hundreds of collaborators and huge, complex apparatus.
“What I was looking for,” Johnson writes, were 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.”
Galileo the Singing Physicist
The curious souls made some unusual uses of the materials they had at hand.
Galileo’s early 17th-century inclined plane experiments measured the acceleration of gravity. As the balls rolled down the ramp, Galileo – a trained musician – marked the units of time by singing. Galileo established the modern field of physics, as well as the modern practice of astronomy.
To map the functions of the heart, 17th-century physician William Harvey conducted experiments that ranged from slitting open a snake to placing a tourniquet on his own arm, watching arteries throbbing above the tourniquet and veins throbbing below the tourniquet. His ultimate discovery: the right side of the heart pumps blood through the lungs, the left side of the heart pumps blood through the body.
In his 18th-century experiments on the interference of light waves, Isaac Newton went so far as to stick a thin, blunt probe into his own eye socket, as close to the back of the eye as he could manage. Pressing the probe, he could see light and dark circles. He moved on to prisms, to study the refraction of light into its component colors or wavelengths.
From Combustion to the Charge of an Electron
Filling out Johnson’s list of 10:
- Lavoisier's explanation of the nature of combustion, including indications of conservation of matter;
- Galvani's exploration of electricity in muscle movement, also spurring Volta’s battery development;
- Faraday demonstrating the unity of electricity and magnetism;
- Joule establishing the equivalence of heat and work as two forms of turning energy into motion;
- Michelson disproving the presence of “aether” by showing the absolute nature of the speed of light in all directions;
- Pavlov's salivating dogs
- Millikan setting the definitive value for the charge on an electron, the basic unit of electrical charge.
In researching “The 10 Most Beautiful Experiments,” Johnson replicated many of the procedures with equipment salvaged from a junk yard. Johnson concludes by mulling over a few considerations for an 11th “Most Beautiful Experiment,” but the best choice for No. 11 would be this book itself.
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