Han Earthquake-detecting Machine Model - 2
MAY 15 2010
Henan Provincial Museum, Zhengzhou. Complete indexed photo collection at WorldHistoryPics.com.
Source: Wikimedia Commons
Part of Underground · Watch in the documentary
MAY 15 2010
Henan Provincial Museum, Zhengzhou. Complete indexed photo collection at WorldHistoryPics.com.
Source: Wikimedia Commons
Part of Underground · Watch in the documentary