I had been before to the Long Museum, just before it opened eighteen months or so ago.   It’s an impressive, large scale, concrete structure based on surviving industrial remains.   What I hadn’t expected was a scholarly exhibition in the basement devoted to The Imperial Art of the High Qing, art which survives in Chinese private collections from the reigns of three Emperors – Kangxi, Yongzheng and Qianlong.   What wasn’t clear was where the works had been during the cultural revolution.   Were they hidden or have they been bought back from the west ?