During the Senate's antebellum era, frustration intensified as senators sought a compromise to keep the Union intact despite the ceaseless pressure of the slavery dispute. Antagonism between Mississippi senator Henry Foote and Missouri's Thomas Hart Benton was evidence of the tensions that had caused Vice President Millard Fillmore to warn senators that he would not tolerate violation of the Senate's rules requiring civil behavior. The Benton-Foote friction erupted dramatically on April 17, 1850, when, during a particularly heated exchange, Benton advanced menacingly in Foote's direction. Foote reacted by pulling a pistol. After several tense moments, Foote surrendered the weapon and the members separated the would-be combatants.