Bill of sale for a slave named Mark, dated March 11, 1799 that was signed and sealed by Jeremiah Bennett. While not original to Arlington, such a document would have been used there. This bill of sale,similar to a receipt, gave the holder ownership of an individual slave. Buying and selling slaves was common practice for land owners of the period. Mr. Custis bought and sold slaves as a younger man but largely discontinued the practice as he aged. He did attempt to keep families together as much as possible. After the death of his father-in-law in 1857, and facing enormous debts, Robert E. Lee began hiring out slaves, a dozen over the next few years. This caused hardship and anxiety among the slaves at Arlington, even prompting some to run away. By the terms of Mr. Custis’s will, they were all to be freed within five years of his death. Although he challenged it in the courts, Lee was bound to fulfill those terms and manumitted the slaves in December, 1862.