Robert W. Wood
The Scientist who Played with Optics Optics
Robert Williams Wood viewed the natural world as his playground.
For him, science was a highly creative endeavor to be approached with
curiosity and awe. Wood was also a scientific maverick who consistently
questioned all dogmas. Above all, he was an experimentalist: He tested
conclusions, built his own apparatuses, and was excited about every
part of the process. Wood discovered resonance radiation and greatly
expanded our understanding of ultraviolet light.
AIP Emilio Segre Visual Archives, gift of David L. MacAdam
obert W. Wood was born in May of 1868 in Concord, Mass., U.S.A. He attended
the Roxbury Latin Academy with the intention of becoming a priest. However, that
plan didn’t last long, as he soon became fascinated with the natural world.
By the time he attended Harvard, between 1887 and 1891, he knew he wanted to pursue
a scientific life. He was a creative and highly independent thinker, and his personality often
clashed with the rigidity of his professors. From an early age, Wood wasn’t afraid to question
the establishment. For example, when Wood’s geology professor and mentor Nathaniel Shaler
described his glacier theory—in which Shaler posited that high pressure at the bottom of a
glacier would convert the ice to water—Wood didn’t hesitate to construct an apparatus to test
Shaler’s conclusion. Wood’s device was made from a block of aluminum and a tightly fitted
moveable aluminum cylinder. Inside the bore, Wood placed snow that contained a lead bullet
that had been suspended off the bottom.
Wood put the device in subfreezing temperature and then subjected the cylinder to pressures
that greatly exceeded those at the bottom of a glacier. If the ice formed water, as Shaler had predicted, the bullet would fall to the bottom of the bore. However, when Wood disassembled the
frozen apparatus, the bullet remained suspended in the ice above the bottom of the bore, thus
debunking Shaler’s theory. Wood published the result in the American Journal of Science.
Wood also wasn’t afraid to delve into unconventional areas. After conferring with Prof.
William James—a pioneering psychologist—Wood decided to test the psychological effects
of cannabis indica—a plant containing the same psychoactive molecule as marijuana. He
wrote his personal account of the experience, which was published in the New York Herald on
September 23, 1888, and excerpted in James’ Varieties of Religious Experience.
Wood graduated from Harvard with an honorable mention in chemistry and natural history.
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