Exhibition "Secrets of the Celestial Empire" held in Moscow

People look at the exhibits during the exhibition "Secrets of the Celestial Empire" in Moscow, Russia, on Oct. 12, 2017. The exhibition, held from October 12 to November 5, displays such exhibits as paper, silk and the seismoscope invented by Chinese inventor Zhang Heng (AD 78-139). (Xinhua/Evgeny Sinitsyn)