Hall of Celestial and Terrestrial Union Pictures

The name, as well as the position of this hall, signifies that union of the celestial and the terrestrial can generate harmony and peace. It was a place for the empress to receive greetings on major festivals and her birthday. It was also a place for storing the twenty-five different imperial seals. There is a copper clepsydra (water clock) on the left and a mechanical striking clock on the right inside. These were used to set the standard time in the Forbidden City.