'Time by the stars'

The observatory's back rooms and second floor, which have been seen by very few of those million young visitors, are almost a museum of turn-of-the-20th-Century technology.

The observatory is the last surviving part of the old Elgin National Watch Co. complex, which once took up a large square block along National Street opposite the end of South Grove Avenue. Through much of Elgin's history, the plant employed a third to a half of all workers who lived in the city. It made Elgin world-famous for quality manufacturing.

In an era before atomic clocks and vibrating crystals, the company opened the observatory in February 1910 as a way to figure out exactly what time it was, by looking at the stars.

"When I came as a kid," Hernandez admits, "I thought the dome on which the stars are projected over the students' heads was the same dome you can see from outside the building." But the dome visible from Watch Street is one story higher than the planetarium dome and much smaller. It actually held — in fact, still holds — the 10-foot-high, 101-year-old transit telescope, equipped with cross hairs made of spider's silk, that watch company workers used to aim at the stars every night.

To keep it from fogging up or being affected by vibration, the domed telescope chamber is unheated, and the scope rests on a concrete pier extending 60 feet into the ground. On each clear night in the early 1900s, employees would crank open a viewport in that first dome, put their eyes to the scope and click a push button every time a certain expected star moved exactly past the spider-silk cross hairs. These markings then would be used to determine exactly what time it was, with as much precision as anything could in 1910.

That time, in turn, was sent down a wire to a room in the watch factory across the street where women — it was usually women because they had smaller fingers, Hernandez says — would set the hands on expensive Lord and Lady Elgin watches about to be sent out to jewelry stores.

The time was stored on two German-made pendulum clocks in a room heated by a bank of light bulbs along the floor. To keep the clocks' temperature at exactly 81 degrees, workers would turn off or turn on more light bulbs.

Later, the company also began broadcasting its exact time over radio waves to commercial radio stations. At 6 p.m. WXYZ Radio in Chicago might say "the time at the tone is exactly 6 p.m. at the Elgin National Watch observatory in Elgin, Ill."