Mayor Alexander Henry of Philadelphia warned that an upcoming lecture by abolitionist George W. Curtis at the People's Literary Institute on Market Street was a planned target of anti-abolitionist rioters. The owner of the hall then next day reinforced this. Abolitionists refused to be intimidated, though, and the lecture went on at the appointed time, with the Mayor and 600 policemen defending the doors against brick throwing rioters. (By John Osborne)
Source Citation
The American Almanac and Repository of Useful Knowledge (Boston: Crosby, Nichols, Lee and Company, 1861), 406.