What did the south think of the 36 30 line?

Condemned by some Southerners because it set the example that Congress could make a law concerning slavery.

Explanation:

The Missouri Compromise of 1820 established the latitude 36°30′ to deal with the growing slave states in the western territories. The North always considered slavery as a part of the evil which should be banned. As the South economy depended on slaves, the Union could not interrupt it in existing states. The compromise of 1820 divided the Louisiana Purchase land into two sections. Slavery became forbidden above the Missouri compromise line latitude 36°30 and admitted in the south of latitude which allowed Missouri to became a slave trade.

equal area projections

equal-area projection. a projection in which regions on the earth's surface that are of equal area are represented as equal.