So, I was attempting Direct North Buttress in Yosemite with Charlie Sassara, and I was stuck below one of that insecure climb's run-out face sections, four or five pitches up. I kept stepping up from a good foothold, groping at the slippery holds, and then stepping back down for more chalking up and wistful tugging at the bad nut by my knees. After two or three rounds of this, as I lingered on my foothold, a park ranger cruised below Middle Cathedral and briefly touched his siren to make one of those bleats designed to warn pedestrians or scare cyclists into the bushes. Without missing a beat, Charlie looked at me, assumed a PA voice, and said sternly: "Sir! Step away from the ledge!"