Neptune discovery telescope. The telescope at New Berlin Observatory (1835â1913), that discovered Neptune, was an achromatic refractor of 9 Paris inch (9.6 English inches or 24.4 cm) aperture made by the late Joseph Fraunhofer's firm, Merz und Mahler.
The southern states needed these slaves because the southern states had more farms and plantations than the North did. Not everyone could afford slaves; slaves were really expensive. They were expensive to buy because they had to be feed and taken care of.
2017-08-17T15:57:39-04:00. The cotton gin was the invention which helped to keep slavery profitable in the south. With cheap labor for picking cotton, farmers also needed a cheap way to refine and process the cotton prior to distribution. The cotton gin enabled this function and kept costs low in the process.