Spinning Jenny by John James, History of the Worsted Manufacture in England; Metropolitan Museum of Art

In 1812, Jefferson expanded and mechanized cloth manufacturing at Monticello, establishing a textile workshop in a building along Mulberry Row originally constructed as housing for free white workers, and introducing two 18th-century inventions – the loom with a "flying shuttle" (1733) and the "spinning jenny" (1770) – that greatly increased the amount of cloth his enslaved spinners and weavers could make.

By 1815, a dozen enslaved women, girls, and some young boys – working as spinners, weavers, carders, and quillers – made cloth from wool, hemp, and cotton in the textile shop. Thanks to their labor and to the new looms and jennys, Jefferson could report, "I make in my family 2000. yds of cloth a year, which I formerly bought from England, and it only employs a few women, children & invalids who could do little in the farm."

Randal and John Hern, two young carders, used hand cards or a carding machine to brush the raw material into long rolls of fiber called roving.  Aggy, a spinner, fed the roving onto a spinning jenny, which separated the fibers before twisting them into thread and winding them onto 24 different spools. Eliza, a young quiller, removed the spools from the spinning jennies and brought them to a loom. Dolly then wove the thread into cloth on a fly-shuttle loom. The enslaved workers were instructed by William McLure, a hired weaver who worked at Monticello from 1812–14.