Illustration of 'salt gall water' (yandan shui) from Shiwu bencao (Materia dietetica), a dietetic herbal in four volumes dating from the Ming period (1368-1644). The identity of the author and artists is unknown. It contains entries on over 300 medicinal substances and is illustrated by almost 500 paintings in colour.
This illustration depicts the procedure for obtaining 'salt gall water' . Salt is first extracted from sea water by heating. The hot salt is then put in a wooden trough with a drain, below which is placed a vessel to catch the dark liquid that runs out of it. This is salt gall water, also known as brine (lushui) - See Image L0039378.
The text states: Salt gall water is salty and bitter in sapor, and highly poisonous. It must not be consumed by human beings or domestic animals.
