The pina, also known as the Oracle, acts to capture much of the energy of the mechanical wave and transmits that mechanical wave through the ear canal, which is basically this portion here. So the ear canal is also part of the outer portion of the ear. Now, the mechanical wave then moves along the ear canal and towards the end of our ear canal. And at the end of the ear canal, we have the beginning of the middle ear. So we have the propagating mechanical wave. Some type of disturbance in the air initiates this propagating wave, our mechanical wave.