Some slaves/servants were highly-skilled domestic craftsmen. The novel’s widow Parthenia Leila Ellis’s housekeeper/slave Natalie, for instance. Natalie was skilled at sewing French seams even in silk, while her mistress was afraid of sewing silk at all.
The French seam remains in use because it is a deft way of concealing raw edges of cloth. It is sometimes used on the outside of dresses and other garments. Natalie’s skill was one reason Leila Ellis hoped to employ her for wages after Emancipation took effect in Tennessee.