By 1815, enslaved spinners, weavers, carders, and quillers made cloth from wool, hemp, and cotton in the textile shop. 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.