Figure 39. Section from Canon 1 (page 3 of score), showing two unarticulated CPs and their leader-follower switches, pitch symmetry about these switches, and near-synchrony at second switch. Both voices are decelerating in this passage. Sustaining of notes is indicated by horizontal lines. The longest echo distance is reached halfway between the two leader-follower switches; selected echo distances are shown by circled notes connected with a line.