Eliza was 16 years old when she became responsible for managing Wappoo Plantation and its twenty slaves, plus supervising overseers at two other Lucas plantations, one inland producing tar and timber, and a rice plantation on the Waccamaw River. In addition she supervised care for her extremely young sister, as their two brothers were still in school in London. As was customary, she recorded her decisions and experiments by copying letters in a letter book. This letter book is one of the most impressive collections of personal writings of an 18th-century American woman. It gives insight into her mind and into the society of the time.