A phone call that produces no audible sound at eighty meters in open air. Not whispered — whispered speech at ten meters is audible with attention. Silent. The device held to the ear and the body producing none of the micro-gestures that accompany actual speech: no jaw movement, no throat movement, no shift of breath rhythm. You breathe differently when you are speaking. The body knows how to breathe around words. His body was not doing that. He was holding the device to his ear without speaking, for the duration I observed him, which was four minutes and some seconds before he cleared the corner.

The phone is the second prop. The clipboard is the first — it implies accountability without inviting questioning, because people with clipboards are presumed to be working and working people are presumed to have legitimate reason to be where they are. The phone is a deterrent to approach. A man on a call cannot be interrupted, or he can be interrupted only at social cost that most people are not willing to incur in public. The phone is a social barrier that he is wearing.

Two props in simultaneous use on one occasion would be unusual. I have not seen him use both at the same time. The clipboard has been consistent. The phone appeared in the sixth occurrence only. A possible interpretation: the sixth occurrence was a different kind of engagement than the previous five. The addition of the phone barrier suggests that on this occasion there was a specific reason to be less approachable than before. I do not know what that reason is. I know I was on a spontaneous route. I know he had upgraded his deterrent posture.