Cochlea a protein motor called prestin on their outer membranes; it generates additional movement that couples back to the fluid–membrane wave. This "active amplifier" is essential in the ear's ability to amplify weak sounds. The active amplifier also leads to the phenomenon of soundwave vibrations being emitted from the cochlea back into the ear canal through the middle ear (otoacoustic emissions). Otoacoustic emissions are due to a wave exiting the cochlea via the oval window, and propagating back through the middle ear to the eardrum, and out the ear canal, where it can be picked up by a microphone. Otoacoustic emissions
Fantastic Beasts and Where to Find Them described hereafter are fictional and cannot hurt you." He repeats the Hogwarts motto: "Draco dormiens nunquam titillandus", Latin for "Never tickle a sleeping dragon". "Fantastic Beasts and Where to Find Them" contains the history of magizoology and describes 85 magical species found around the world. Scamander says that he collected most of the information found in the book through observations made over years of travel across five continents. He notes that the first edition was commissioned in 1918 by Augustus Worme of Obscurus Books. However, it was not published until 1927. It is now in its fifty-second edition. In the