https://en.wikipedia.org/wiki/Patuxent_Iron_Works

""In 1831 the furnace and forge were sold by Thomas, Richard and Edward Snowden"

"According to tax records, the company had on average 45 enslaved workers from 1760 to 1780, who worked as foreman, founders, laborers and blacksmiths. Though both the Snowdens and Cowmans were wealthy Quakers whose children intermarried, they owned slaves for a century."