When a drop of water fell, a ripple appeared on the mirror beneath the dust.

Last time the leaf dust was unprepared, so it was impossible to see the track of these ripples after only a moment's observation.

But this time, Ye Du can see clearly.

This drop of water fell on the mirror, and the first ripple rippled out immediately. This ripple soon triggered a ripple on the mirror. These ripples spread around, but the farther they spread, the weaker they become.

At the beginning, leaf dust can clearly see the existence of these ripples, and keep counting the number of these ripples in mind.

But just looking at...