Early in the 20th century Hong Kong was a bustling port city with people of many nationalities [especially sailors] who didn't speak Chinese. Most bordellos had these small folding books of various sexual acts available to help bridge the language barrier. The actual book unfolds like an accordion, showing 10 different scenes of sexual acts.

Virtually none of these pictorial menus survive today, most are locked away in museums, unavailable to the public due to the contents! In over 50 years of collecting rare erotica, this is the only one I've seen for sale. I have asked several older Chinese people to translate the Chinese characters on the cover page, but all who were willing to look at it would not tell me what it says, they seemed to be too embarrassed! 

Condition note: Sometime in it's life this folding book got wet along one side where the pages fold together, and there is slight water discoloration along those folding edges. This can be seen in the photos.