Yerkes Observatory The Wallace Spectroscope “Reticent Quintessence”
The Yerkes Observatory, nestled on the shores of beautiful Lake Geneva in Williams Bay, Wisconsin, has been a cornerstone of my life for nearly half a century. My journey with this historic institution began in my teens. When I received my drivers license at 16 it was one of my first destinations. Being from the Chicago area it was an easy trip on my motorcycle and Lake Geneva was happening.
I spent summer days painting the observatory from its grounds and later in life marveling at the stars through its 62-foot refracting telescope. One of my most cherished memories is witnessing Halley’s Comet in 1986 through its magnificent telescope.
The World’s Largest Refracting Telescope.
P. A. Baron at the telescope.
Video. https://youtu.be/ExohRxE06ss?feature=shared
Yerkes site. https://yerkesobservatory.org/
Built in 1895, the Yerkes Observatory’s telescope boasts the world’s largest refracting lenses, each measuring 40 inches in diameter and weighing 500 pounds. Made from crown glass and flint glass, these lenses have a 62-foot focal length. Owned by the University of Chicago, the observatory has been instrumental in several astronomical discoveries and is recognized as a birthplace of modern astrophysics. Today, it continues to attract renowned astronomers and contribute significantly to the field.
Among the many treasures associated with Yerkes, one stands out: the Wallace Spectro-Scope. This simple yet powerful device allows the user to view the spectra of any light-emitting source. It has been a constant companion of mine, often found in my pocket, ready to unveil the spectral secrets of the universe. The only other known Wallace Spectro-Scope is housed at the Smithsonian Institution.
Instrument Description
The Wallace Spectro-Scope, inscribed with “WALLACE / SPECTROSCOPE / CENTRAL SCIENTIFIC CO. / CHICAGO,” employs a replica diffraction grating instead of a traditional prism assembly. This design was pioneered by Robert James Wallace (1868-1945), a photographer at Yerkes Observatory.
Above. A self drawn cartoon of himself in 1907.
Mr. Wallace. “A lemon in the garden of love”
For more details, see the Smithsonian’s record.
https://www.si.edu/object/spectroscope%3Anmah_1463303
For further reading, refer to Robert J. Wallace’s work on diffraction gratings in the Astrophysical Journal.
https://ui.adsabs.harvard.edu/abs/1905ApJ....22..123W/abstract
Albert Einstein’s connection to Yerkes Observatory is limited to a single, brief but notable visit on May 6, 1921, during his first trip to the United States.
Details of the Visit
• Duration: Approximately four hours.
• Context: Einstein had just risen to international fame following the 1919 confirmation of his general theory of relativity. On this U.S. tour, he specifically requested to visit only two places: Niagara Falls and Yerkes Observatory. The observatory’s reputation as a leading center for astrophysics (home to the world’s largest refracting telescope at the time — the 40-inch Clark refractor) drew him there.
• Activities: He toured the facility, met with staff and faculty, and was photographed with them under the iconic 40-inch refractor telescope. The photo shows Einstein with observatory personnel and visitors — a well-documented historical image available in University of Chicago archives and Yerkes collections.
• Significance: It was front-page news locally (e.g., The Lake Geneva News). Einstein reportedly expressed greater interest in seeing Yerkes than many other landmarks. He did not conduct research or give a formal lecture there; it was more of a scientific pilgrimage and tour.
Why wasn’t Wallace in the photograph?
Wallace’s Role: Robert J. Wallace (1868–1945) was the staff photographer at Yerkes. It is quite possible (even likely) that he took the photo or assisted with it, rather than appearing in it.
A Lasting Legacy
The Yerkes Observatory and its instruments, like the Wallace Spectro-Scope, symbolize the enduring quest for knowledge and the beauty of the cosmos. These tools and the observatory’s legacy continue to inspire new generations of astronomers and enthusiasts, ensuring that the spirit of discovery remains alive.
P. A. Baron
“Reticent Quintessence”