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: Bleeding Kansas. Proposed by Sen. Stephen Douglas of Illinois, the Kansas-Nebraska Act essentially repealed the line imposed by the Missouri Compromise. Douglas, an ardent believer in grassroots democracy, felt that all the territories should be subject to popular sovereignty.
The causes of the civil war have been a point of contention lately. First of all, its causes were economic. The North relied on the South's agriculture for its industrial wealth. When you add to this the problem with slavery, which was also economic but philosophical too.