5 Things to Know About Thomas L. Jennings, The First Black Patent Holder

Dry Scouring 

After hearing from customers about hard it was to get out stains, Jennings began to experiment with ways to clean tough stains and grime out of clothing. His process was called dry scouring. Sadly, the intricate details of the process were all lost in a fire. From what is known, Jennings used a detergent of his own making to scour or rub hard onto clothes until they had a sheen and were clean.