On October 10, 1860, at Cooper Union Hall in New York, Yancey advised Northerners interested in preserving the Union to "enlarge your jails and penitentiaries, re-enforce and strengthen your police force, and keep the irrepressible conflict fellows from stealing our negroes..." Yancey cited southern fears that with abolitionists in power, "Emissaries will percolate between master slave as water between the crevices of rocks underground. They will be found everywhere, with strychnine to put in our wells." He further warned the crowd that Republican agitation would make Southern whites "the enemies of that race until we drench our fields with the blood of the unfortunate people."