Why do echoes in the alley at night?

At night, a person walking in a small alley, in addition to his footsteps, also heard a kind of “rustling” again, as someone followed. It often makes pedestrians a little panicked, mentally tense.

As long as you understand the inner scientific principle of things, there is no more fear of ghosts and spirits. People walking on the ground will make footsteps. The sound of hitting the walls of two small alleyways will create echoes like a leather ball thrown back. During the day, passersby echoes are absorbed by passersby bodies, or obscured by background noise, so that footsteps can only be heard.
At a late-night, the situation is different. At that time, the person walking in the alley, in addition to the sound of his footsteps, could hear the echoes reflected from the walls of the two small alleys. The alley is very narrow; echoes of footsteps after hitting the wall can also produce reflexes. The narrower the alley, the more reflexes. At that time, a “stirring” echo could be heard. That is called vibrating echoes.
In our lives, any phenomena and things contain a certain scientific principle. As long as you pay close attention to, brainstorm, you will learn more and more scientific knowledge right around you.