The south approved slavery because slaves were useful to them on their cotton farms. However, after the invention of cotton gin many saw that they didn’t need to slaves to work for them on the cotton fields anymore as it was easier to own a machine which would do the work instead. They saw the slaves as pointless and impractical after the invention.
Answer:
They used a sundial. Sundials consisted of a tall vertical or diagonal-standing object used to measure the time, called a gnomon. Sundials were able to measure time (with relative accuracy) by the shadow caused by the gnomon.
Explanation: