His cotton gin (short for engine) revolutionized the southern economy

A bond is a certificate issued by a government or a public company promising to repay borrowed money at a fixed rate of interest at a specified time. By taking a bond, the government is in a legal contract that says they should pay back the money they borrowed. However, not all citizens think the money borrowed should be paid back.  

Some peeople believed the federal government should not pay back bond debt because they believed it's unfair that debts should be paid to the estates of people who had died during the war effort.