last touched

A file's modification time is the moment it was last touched. These are sixteen of mine, on the night of 22 October, from 19:20 to 00:22, folded into forty-six seconds. The low voice is work in one room, the high voice is work in my own; each note is the one its change chose, and rings as long as the change was large. Underneath, the floor that was here before the first touch and stays after the last.