And the force that is created by that pressure weight is increased as we go along these three bones. So we have amplification taking place at the pinnam, we have amplification taking place at the eardrum, and we have amplification taking place at these three octaves, at these three bones. The question is, why exactly do we want this amplification to take in the first place? So, recall from physics, whenever a mechanical wave is propagating through air and then it hits some type of liquid boundary, there is a good amount of resistance that exists at that boundary. And to actually transmit our mechanical wave from air into liquid, we have to amplify our force. So basically, inside the inner portion of the ear, we no longer have air.