“THE COMET AND PLANET BUSINESS. – Are not our scientific friends in Harvard, and elsewhere, carrying this planet and comet business rather too far? A new planet in the course of three or four years, and a comet a year, will do very well, but this finding a planet every week, and a new comet daily – is it not running the thing into the ground?… (Reprint from the Providence Journal in the Cambridge Chronicle May 29, 1852.)
Selling time? Huh? Read on. To celebrate International Astronomy Day on April 29, we’re taking a brief look at the Harvard College Observatory. Volumes have been written about the Observatory and its scientific achievements, so this post will focus on the beginning years.
It turns out that an observatory is useful for a lot more than just looking for stars in outer space: observatories are crucial to finding your way around down here on Earth, too. As it says on the Smithsonian Institution website: “If you want to know where you are, you need a reliable clock.”[i] But what does that have to do with “selling time?”
In the early 1800s, Europe was far ahead of the U. S. in terms of astronomical research—just think of Copernicus or Galileo. By 1825, Europe was home to at least 130 observatories.[ii] Although faculty at Harvard had begun thinking about building an observatory as early as 1805, it was not until 1815 that the Harvard Corporation voted to “consider upon the subject of an Observatory.” It took another 14 years for this expensive project to emerge. In 1839, the first iteration of the Observatory was organized on the grounds of the Dana House on Quincy Street in Cambridge, near the present-day Houghton Library. The Dana House was moved in 1947 across the street to its current location at #16 Quincy St.
That same year, the most local reliable timekeeper was William Cranch Bond (1789-1859), a well-known clockmaker and an amateur astronomer. Harvard was happy to accept Bond’s offer of his own private equipment for the first observatory. Bond’s marine chronometer (the scientific name for a very precise time-measuring device used to determine longitude at sea) was so accurate that it was used by the U. S. Navy. Bond was subsequently appointed the first “Astronomical Observer to the University”—then, a position without pay. At the time, the observatory was referred to in the press as the “Cambridge Observatory.” In 1847, Bond was appointed as the first director of the observatory at its new location at 60 Garden Street.
(William Cranch Bond is buried in Mount Auburn Cemetery, Lot 1814 Geranium Path)
A second building, erected to house the Lloyd Magnetic apparatus for measuring the meridian, had to be built near the Dana House. To do so, the College had to “purchase the privilege of tunneling under a neighboring building in order to procure a sight of the meridian mark.” The building was constructed with no use of iron, which would have distorted magnetic readings. A concurrent development was taking place in Europe, the use of which would affect the work of astronomers across the globe: in 1839, Louis Daguerre invented the daguerreotype, which enabled the scientists at the Observatory to capture images of astronomical sightings, rather than drawing them by hand.
The Unknown Comet that Changed Everything
In 1843, a previously unknown comet seen by the naked eye zoomed into view, generating immense interest among the population:
Harvard seized the opportunity created by the comet craze to launch a fundraising campaign to acquire high quality instruments and a more suitable location for the Observatory. So it was that in 1843, ground was broken for the Observatory on what was then known as “Summer House Hill” at its current location, 60 Garden Street. Meanwhile, orders were being placed in Europe for the best telescopes and instruments, including what would become the largest telescope in the United States—The Great Refractor.
By 1847, the observatory was up and running. The building was oriented to North/South for the purpose of celestial measurements, (rather than parallel to the street), and made earthquake proof. The telescope’s granite base extends 26 feet below ground and is 43 feet high from the ground up. Most spectacularly, the glass lens, shipped from Germany, was installed on top of the gargantuan base—known the Sears Tower, named for Boston philanthropist David Sears, who was a major player in raising money for the new observatory in 1839.
The crush of visitors to the telescope (at no charge) was so huge such that director Bond wrote to the President of the University (Edward Everett) to reverse the university’s policy of open visitation:
“…the number of visitors has been constantly on the increase for several weeks. On the last public evening there were probably four hundred persons present. These crowded into a space of thirty feet in diameter, the mass rapidly condensing near the point of observation, rendered the management of an instrument of several tons weight, and so nicely balanced as to be turned by a finger, extremely hazardous; while from the quick succession in which the observers were obliged to follow each other, affording perhaps upon an average of a quarter of a minute to each one, it was impossible that any individual could derive much instruction.” (The Cambridge Chronicle October 28, 1847). Bond was also concerned about the amount of dust raised by all those visitors tramping over the floorboards infiltrating the delicate mechanism.
In addition to the Great Refractor dome, rooms for other magnetic equipment needed to be built. These included the equatorial room, the transit circle room, the prime-vertical room, and locations for the meridian-transit instrument, the horizontal-force magnetometer, the declination magnetometer, the reading telescopes, the small altitude and azimuth instrument, the transit (or sidereal) clock—got that? Once again, these spaces were constructed using no iron.
Once the Great Refractor was installed, scientists began taking photographs. Photographs taken at the observatory greatly amplified the knowledge of stars, planets, and constellations. In 1849, photographer John A. Whipple (1822-1891) took a daguerreotype of the moon on Harvard’s Great Refractor (shown below). This image won Whipple a gold medal at the Crystal Palace exposition in London in 1851.
After photographic means were further developed, the observatory began creating negatives on glass plates measuring 8” x 10”. By 1893, the number of glass plates amounted to 30,000 and in total weighed nearly eight tons!
Below is an example of a glass plate negative. The three big circles are the constellation Orion’s Belt. See all those little dots that look like dust? Those are also stars or constellations. It was all hands on deck to find people to analyze and catalogue each dot. And those people were women.
The women were called “computers.” Hired by the observatory beginning in 1875, the computers were paid 25-30 cents/hour and worked six days a week. The pioneer of this cohort seems to be Miss. Rhoda G. Saunders, who was hired for $600 per year in 1875, and worked at the Observatory until 1888, when she got married. Saunders first appeared listed as a “computer” in the Cambridge City Directory of 1877:
The image of a broken glass plate below illustrates how fragile the plates were, as well as the identification numbers added by the “computers.”
The next image shows how the glass plates were historically stored when not in use—each in its own annotated file on the shelves. Also seen to the left of the shelving stacks is a group photo of the women computers:
Hiring women for scientific work was such big news that it made it as far as a newspaper in Wisconsin:
Click here for a list of women astronomical computers at Harvard.
By 1893, the Observatory needed new storage space for all the glass plates. By running a pulley along a rope to the storage site in a new building, they managed to move all the plates without breaking one. The rate of transfer was about 6,000 plates per hour. Today, there are over 500,500 glass plate negatives of photographs of stars, planets, and constellations in the Astronomical Photographic Plate collection.
FUN FACTS ABOUT THE HARVARD-SMITHSONIAN OBSERVATORY
– Observatory Hill. Once the Observatory was relocated to Garden Street, people began referring to the area in general as “Observatory Hill.” In 1895, the Cambridge Chronicle established a regular column titled “Observatory Hill” to relay the goings on in the neighborhood.
– Selling time. How can one sell time? Turns out it was big business. The proliferation of railroad companies, each running their trains on separate timetables, created dangerous problems. Once again, our hero William C. Bond came to the rescue. Bond and his sons developed a prototype for transmitting accurate time measurements they called the “Spring Governor.” By 1851, the Bond family had perfected the technology and were able to send electronic signals from the clocks in the Cambridge Observatory to clocks in Boston through telegraph wires. The railroads were interested, and soon Harvard was “selling time”—in other words the Bonds sold rights to use their time system. Harvard made about $2,400 per year with the enterprise until the U. S. Naval Observatory took over time standardization.
– Outpost observatories Thanks to a large donation in 1890, Harvard was able to set up an observatory station in Arequipa, Peru. It was named the Boyden station, after Uriah Boyden, a Boston civil and mechanical engineer, and the inventor of the Boyden turbine. In 1926/27 the Boyden station in Arequipa was moved to Bloemfontein South Africa.
– The Smithsonian connection. In 1955, the Smithsonian Astrophysical Observatory relocated to Cambridge, and in 1973 the Smithsonian and Harvard Observatories combined, forming The Center for Astrophysics | Harvard & Smithsonian.
– The end of glass plate negatives. By 1992, advanced technology had made glass plate negatives obsolete, and the program was shut down.
We leave you with these somewhat hokey astronomical jokes:
“It is said that in space, no one can hear you laugh. That explains the silence.”
“The rotation of the earth makes my day.”
“What did Mars say to Saturn? Give me a ring sometime.”
Image: View of Harvard College Observatory 1893-1930.
Photographer unknown. Harvard Plate Stacks Collection
Today’s post was written by CHC volunteer Kathleen M. Fox.
SOURCES
Robert Sears. A Pictorial Description of the United States. 1852
Selling the True Time: Nineteenth Century Timekeeping in America. Ian R. Bartky. Stanford University Press, $57.95 (328pp) ISBN 978-0-8047-3874-3.
https://www.harvardmagazine.com/2015/08/william-cranch-bond. Issues September-October 2015, by Alan Hirshfeld
https://library.cfa.harvard.edu/plate-stacks/collection-timeline
https://library.cfa.harvard.edu/plate-stacks/women-at-hco
https://library.cfa.harvard.edu/rhoda-g-saunders
Harvard Crimson February 16, 2017 by VALERIE B. ELEFANTE
Harvard Crimson https://www.thecrimson.com/article/1947
https://oceanservice.noaa.gov/
https://www.britannica.com/biography/William-Cranch-Bond
https://www.scientificamerican.com/article/a-chronicle-of-timekeeping-2006-02/
[i] https://timeandnavigation.si.edu/
[ii] https://www.harvardmagazine.com/2015/08/william-cranch-bond