Ancient Roman laundry.

Clothing was an important indicator of wealth and social standing in ancient Roman culture, and fullonicas provided laundry services to clean their white woolen togas. The best cleanser for sweaty togas was ammonia, and the best source of ammonia was urine. The garments were soaked and agitated in a mix of water, alkalis and urine, then rinsed and dried in the sunshine. A vigorous brushing with thistle restored a fresh look to the togas. Keeping citizens looking neat and tidy, the fullonica laundry was a respected and essential part of ancient Roman society.