Sentence:  Nancy Basset, 28, likely <WSD>wench</WSD>, mulatto / Proved to be free. / Certified free as per General Birch Certificate. / Patience Jackson, 23, very likely <WSD>wench</WSD>, mulatto / Says she was born free Rhode Island. / Certified free as per General Birch Certificate. 
Meaning of the word marked with <WSD> tags:  A black woman (of any age), especially if in a condition of servitude.