"Hats and Bats" (police jargon for steel helmets and "batons")...

"Cops Smash Campus Sit-In ... Rout Rebels in Sharp Battle ... The Lion Tamers Move In at Columbia: Helmeted police scuffle with students sitting on the steps of Columbia University's Low Library early this morning as the students try to block cops' entrance. Hundreds of police, including members of the Tactical Patrol Force, were bused to the beleaguered campus to smash the week-long sit-in in five buildings. When the rebel students ignored police pleas to come out of the buildings, police were ordered in. Violence and arrests resulted." —New York Daily News, Tuesday, April 30, 1968, Page 1.