While some guest speakers raise eyebrows on campus, Walter Hickel, President Richard Nixon’s first secretary of the interior, raised a ruckus. Indeed, the repercussions of his visit were felt for weeks — not because of anything he said but because of the way he was received March 5, 1970. Hickel headlined a conference on “Ecology and Politics in America’s Environmental Crisis,” but his speech, . . . was overwhelmed by student anger at the Vietnam War. While most of his listeners in Jadwin Gymnasium kept their views to themselves, a group of 75 hecklers unleashed a barrage of jibes, chants, and cries.