 Complete the following phrase:  Beginning in the 1830s, the U.S. Postmaster General refused to allow the mails to carry abolition pamphlets to the South. Northern teachers suspected of abolitionism were expelled from the South, and abolitionist literature was banned. One Northerner, Amos Dresser 18121904, in 1835 was tried in Nashville, Tennessee, for possessing anti-slavery publications, convicted, and as punishment was whipped publicly. Southerners rejected the denials of Republicans that they were abolitionists. They pointed to John Browns 