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Figure 5. The palace of science, Tower House (Alfred Loomis’s laboratory in Tuxedo Park, NY) was used from 1926 until 1940, when Loomis set up the MIT Radiation Laboratory. Tower House is at present pretty much unchanged on the outside and functions as an apartment complex. Photo courtesy of the New York Public Library, Astor, Lenox and Tilden Foundations.
of Science). In this paper, using the apparatus built in the Tower House (Figure 6), they reported
• acoustic radiation pressures sufficient to support a weight of 150 g;
• the burning of skin or wood when pressed against an ultrasonically vibrating rod;
• the ultrasonic etching and drilling of glass plates pressed against a vibrating rod;
• the internal heating of liquids and solids;
• the formations of emulsions and fogs;
• the flocculation of solid particles suspended in a liquid;
• numerous biological effects, including rupturing red
blood cells, killing microbes, and harmful to lethal effects
on small fish, frogs, and mice; and
• preliminary observations on the effects of ultrasound
on crystallization.
These results, the first reported on the physical and biological effects of ultrasound, still represent a modern-day litany of ultrasonic research (Hinman and Suslick, 2017)! They deferred reports on the chemical effects to work soon published by Loomis and William T. Richards, discussed below in The Chemical Consequences of Ultrasound: William T. Richards. In 1929, Loomis and Woods went on to receive a patent on the use of ultrasound “for forming emulsions and the like.”
After completing their pioneering work together on ultra- sonics, Wood did not continue research on ultrasonics but
instead returned to optics and spectroscopy, sometimes with Loomis as coauthor. Loomis, however, continued to be inter- ested and published several other papers over the next few years on the bioeffects of ultrasound, ranging from bacteria to fruit flies. Wood did eventually publish the first mono- graph on ultrasonics, recounting his earlier work and other developments (Wood, 1939).
The discovery of light emission during ultrasonic irradiation of liquids, oddly enough, was not made by Loomis, Wood, or Richards, despite Wood’s unsurpassed expertise in optics. Indeed, the first observation of sonoluminescence had to wait another 10 years (Frenzel and Schultes, 1934). Personally, I am not displeased that Wood missed that opportunity; he was
the world master of spectroscopy, and there would have been nothing left to discover for those of us working 50 years later (Suslick and Flint, 1987; Suslick et al., 2018)!
Loomis had made a substantial fortune (together with his brother-in-law Landon K. Thorne) financing the largest public utilities and electrifying rural America. Realizing that the stock market was in a speculative bubble, over a few months in early 1929, Loomis and Thorne sold their secu- rities and converted everything into cash and long-term treasury bonds. After the Great Crash (October 1929) and reinvestment during the Depression, Loomis became one of the 10 richest men in America.
Figure 6. Apparatus for early experiments with intense ultrasound. The large coil is a transformer to increase the voltage from the 2-kW oscillator up to 50 kV at 100 to 700 kHz, and the leads from it are connected to a 1-cm-thick quartz plate immersed in oil beneath the flask containing the frog (Wood and Loomis, 1927).
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