riddle - separate with a riddle, as grain from chaff screen sift, sieve, strain - separate by passing through a sieve or other straining device to separate out coarser elements; sift the flour
Causes of the Civil War: Slavery and Control of the Government. Throughout the first half of the 19th century, Southern politicians sought to defend slavery by retaining control of the federal government.
These two parts were the southern states known as Confederacy and Northern states known as Union. The main and the declared cause of the conflict was the issue of abolition of slavery. However there were many other underlying issues adding to the conflicts that resulted in the war.