Semalle's photographs are the first comprehensive record of surviving wooden architecture in Yuanmingyuan. Unfortunately, all of these constructions were believed to have been destroyed in war around 1900, when the Eight-Nation Alliance Force attacked Beijing.

Other key figures from the 19th century contributing to these precious photographic records include Lai Afong, a Hong Kong-based photographer, Ernst Ohlmer from Germany, Osvald Siren, a Swedish scholar, and Thomas Child, a British man who lived in Beijing for 20 years.

Thanks to them, people can now get a glimpse of how Xiyang Lou (Western Mansions)－a combination of the Western Baroque style and traditional Chinese architecture, and an iconic symbol of today's Yuanmingyuan ruins－looked in the 19th century.

It appears that some of the structures disappeared later than people originally thought. A recently released photo from the 1920s shows an exquisite statue of Manjusri Bodhisattva, a Buddhist deity, at Zhengjue Temple, a rare example of a well-preserved structure in Yuanmingyuan. However, this statue was gone by the early 1930s.