Saponification

Food for thought, as you begin the spring ritual of intensive cleaning:

Legend has it that saponification, which is the technical term for soap making, originated in ancient Rome on top of Mount Sapo,where rainwater combined with fish fat and ash (from animal sacrifices), trickled down into the clay soil along the Tiber River. Women, while doing their laundry in the river, found that this clay mixture made their wash cleaner with much less effort.