This is a screenshot from Interactive 1, showing what happens when the user zooms in to the visual representation of the recorded sound in Figure 19. It shows a sine-like waveform with peaks and troughs above and below zero volts. There are equally spaced longer spikes at the fundamental frequency, with smaller spikes in between as the first harmonic. An upward spike is followed by a downward spike, making one oscillation of the wave. There are 23 of these oscillations across the window. The cursor is positioned on the leftmost downward spike and the numbers on the control bar read 0:00:877 / 0:02:519.