Lub-dub Sound Of Heart

He followed the vibration to the very center of the Archive, where a single, ancient tree grew through the floor. Its leaves were translucent, glowing with a pale amber light. He placed his hand against the bark, and the sound grew deafening. Lub-dub. Lub-dub.

But what exactly are you hearing when you press your ear to someone’s chest? Contrary to popular belief, you aren't hearing the heart muscle contracting. You are hearing the "slamming" of the heart's doors. The Anatomy of the Beat lub-dub sound of heart

It is the universal sign of life. But have you ever stopped to ask what is actually making that noise? Is it the muscle squeezing? Is it blood splashing against the walls? He followed the vibration to the very center