Oregon Convention Center: Foucault Pendulum & Dragon Boat

I originally posted the PORTLAND PLACES: Oregon Convention Center page on my old website on October 10, 2008.

…Continued from Expansion & Rain Garden.

Oregon Convention Center Foucault Pendulum, January 28, 2006

Inside the Oregon Convention Center are a number of art installations. The largest of them is the world's largest Foucault Pendulum, which hangs in the convention center's north tower.

Oregon Convention Center Foucault Pendulum, January 28, 2006

Known as Principia, this Foucault Pendulum swings over a suspended 40-foot halo.

Oregon Convention Center Foucault Pendulum, January 28, 2006

The inner rays of the halo go from vertical to horizontal as the halo rotates around the pendulum with the building and the earth itself.

Oregon Convention Center Foucault Pendulum, January 28, 2006

The bronze pendulum bob is 36 inches in diameter and hangs from a 70-foot cable. It makes a 15-foot swing every 15 seconds.

Oregon Convention Center Foucault Pendulum, January 28, 2006

The top of the cable is 90 feet above the floor, so the pendulum swings 20 feet above the lobby.

Oregon Convention Center Foucault Pendulum, January 28, 2006

Beneath the pendulum, a terrazzo floor 30 feet in diameter depicts a fictional solar system.

Oregon Convention Center Foucault Pendulum, January 28, 2006

This is an original installation of the center, created by New York City artists Kristin Jones and Andrew Ginzel and installed in September 1990 by Lathe Tool Works, now known as LTW Automation, manufacturer of most of the world's Foucault pendulums.

Oregon Convention Center Foucault Pendulum, January 28, 2006

A plaque was added later on a nearby wall to describe the pendulum's history and how it works. The text of the plaque is as follows:

FOUCAULT PENDULUM

In 1851, French physicist Jean Bernard Leon Foucault (pronounced "foo-koh") discovered that a pendulum's swing plane would change according to the Earth's rotation. The pendulum appears to rotate, but actually the Earth rotates under it. To keep the 750 pound ball from stopping due to friction, an electromagnetic ring around the top of the cable is turned on each time the ball swings at its lowest point.

The full 360 degree rotation varies depending at which latitude the pendulum is located. At the North Pole on full rotation is accomplished in 24 hours, 33.5 hours in Portland, and no rotation at the Equator.

This Foucault Pendulum was designed by two artisans, Kristin Jones and Andrew Ginzel, and constructed by the Lathe Toolworks of San Francisco. The terrazzo floor was designed and built by Fabrication Specialties of Seattle.

National Association of Watch
And Clock Collectors
Pacific Northwest Chapter 31
In Memory of J. Bryson Moore
February 1999

Note that the plaque states that the weight of the pendulum bob is 750 pounds. The builder's website gives the weight as 900 pounds, and the artists' website gives the weight as 950 pounds. I'm curious if anyone out there has proof of the pendulum's weight.

Oregon Convention Center Dragon Boat, January 27, 2008

Another major item on display inside the convention center is this 40-foot Chinese Dragon Boat hanging in the Oregon Convention Center's east tower. It was custom built in Taiwan and was donated by the Portland-Kaohsiung Sister City Association and celebrates the annual Dragon Boat Races held in the Willamette River during Portland's Rose Festival.

This concludes the original content of my PORTLAND PLACES: Oregon Convention Center page. To see additional blog entries about Portland, click on the Portland label.