MARK WILLIAMSON / SCIENCE PHOTO LIBRARY MARK WILLIAMSON / SCIENCE PHOTO LIBRARY
One of several historical Chinese astronomical instruments at the Beijing Ancient Observatory in Beijing, China, an astronomical observatory that dates from the 1400s. This device, a form of sundial, was used to measure the equinox date; it would have had a gnomon mounted on the pedestal at right. The scale shows an elongated figure of eight.
Model release not required. Property release not required.