The United States National Bureau of Standards (now known as The National Institute of Standards and Technology) was founded by Congress on March 3, 1901, as an authoritative domestic measurement and standards laboratory, and was the first physical science research laboratory of the federal government. Shortly after, in 1908, 26th President Theodore Roosevelt demanded that the NBS encourage precise timing across the nation. This motivated Elgin National Watch Company, from Illinois, to respond by building its own observatory so that the timing in its watches would be scientifically accurate.
Around this time, Elgin was already a well-established entity. The brand was founded in 1864, the idea, for the company, was simple enough, if Massachusetts could build a factory that built watches – Illinois could, too. The idea, for success, was to mass produce high-quality pocket watches using machine-made, interchangeable parts – and it worked. By 1907, Elgin had sold over 600,000 watches—almost one-third of the U.S. market share—and employed 3,200 people.
The purpose of planning and building an astronomical observatory was to signal to the watch factory the correct Central Standard Time. With that, the use of such time continuously was much needed in testing and regulating the thousands of watches that were made daily at the factory. A location was chosen, two blocks from the factory, on the corner of Watch and Raymond Streets – on the high ground of a deep, gravel formation, 85 feet above the Fox River.
Work began, in 1909, Elgin had obtained a three-inch Warner and Swasey transit instrument and two German Reifler astronomical clocks. A temporary house was built, during construction, while the Observatory was under construction and they mounted the transit instrument in it, to take star observations. The latitude was found easily; however, longitude was not as simple. Four nights of observation of 19 stars were exchanged between The Madison Observatory and Elgin with telegraphic time signals. The position of the Elgin observatory was found to be 42.0300 ° N and 88.2733° W.
The work of completing the Observatory building, securing the astronomical and meteorological instruments while properly mounting them consumed Elgin for more than one year.
When completed, the building was unique, in form, and fireproof. The outside walls were smooth with a white painted cement finish. The roof, cornice and dome were painted yellow. The Dome had an opening in the meridian three feet wide, covered by two steel shutters that could open and close. The East part of the building contained the clock room, below, and the transit room, above. Two precision, high grade, self-winding clocks were in airtight glass cases which were hung on an angle on the same pier contained barometers, thermometers and hygrometers to measure the air pressure. The temperature and the moisture in the air were controlled to secure a steady rate for the clocks to keep correct time. The temperature of this clock room was kept at 81 degrees with the help of a thermal regulator and a pair of electromagnetic switches including 57 electric lights. Whether the temperature was 110 outside or 20 degrees below zero, the clock room remained at 81 degrees.
The transit room contained the transit instrument – a small telescope with an extremely precise, graduated mount used for the accurate observation of star positions. The room also contained a level tester, by the Gaertner Scientific Corporation of Chicago, which measured the error of the observed time, by the change of one division of the level during the time of observation and was found generally to be within one-tenth of a second of time.
The reifler clocks were hung, in a small room, on an independent cement pier in a dust tight, wooden case with pendulums adapted to open air and small changes of temperature. A drum chronograph was used for clock comparisons and recording star observations. The chronograph was connected to the clocks for comparison and provided tick marks every second to a key, tied with the telescope. When an event occurred, a tick mark was left on a paper with the second tick marks – allowing the observations to remain focused. Using this, fine clocks were tested whether in beat, or not – an upgrade over the previous eye and ear method.
A personal equation machine, which measured the personal equations, was used to remove personal bias by the observer.
A thermometer cage was placed 15 feet north of the building to prevent the heat of the building from disturbing the temperature of the five thermometers in it. These are set daily at true temperature, at a given time, and then monitored over the next 24 hours to determine the highest, the lowest, and the mean temperature during that day.
The underground wiring is handled through a switchboard connecting the Observatory with the factory for the constant time signals of the observatory is kept accurate within one fifth of a second and is sent in seconds signals to all rooms in the watch factory needing correct time. The signals were also sent to the Chief Business Office of the factory in Chicago and the Drake hotel for broadcasting daily, except on Sundays.
The Elgin timepieces were regulated so thoroughly by the observatory time that Washington D.C. trusted them, for government use, year after year.
After the opening of the observatory, the Elgin National Watch Company adopted the slogan: ‘Elgin Takes The Time From The Stars And Puts It In Your Pocket’.
After WW2, slowly – parts of the company ceased to function. The observatory was abandoned, in 1955, and turned over to School District U46 in 1960. The district opened its doors in September 1963 for students to learn about astronomy under the dome. The building was added to the National Register Of Historic Places, in 1994. Today, the U-46 planetarium has seen over 1 million visitors.
The Elgin National Watch Company factory was once the largest site dedicated to watchmaking in the world. At its peak, it employed over 4500 people, more than half of which were women. During their production run of over 100 years, Elgin produced almost 60 million watches, peaking at over a million watches per year, which is nearly half of all the jeweled watches produced by American watch companies, at that time. They, and their story – including the Observatory, are an American historic treasure.