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: Abolitionism. The issue of slavery was further heightened by the rise of the Abolitionist movement in the 1820s and 1830s. Beginning in the North, adherents believed that slavery was morally wrong rather than simply a social evil.
Causes of the Civil War: The Collapse of the Two-Party System. The tensions between North and South were mirrored in a growing schism in the nation's political parties. Following the compromise of 1850 and the crisis in Kansas, the nation's two major parties, the Whigs and Democrats, began to fracture along regional lines.