A mechanical model of the cochlea in which the skin of the arm is used as a sense organ was compared with the organ of Corti. Three phenomena were investigated: (1) directional hearing, (2) heats, and (3) harmonics. For directional hearing almost no differences were found between hearing and the sensation produced by the model. In the case of beats it was possible to confirm the earlier observations of Helmholtz by improving the frequency resolution of the model ear. Concerning the harmonics it was found that the method of best beats does not permit the measurement of overtones of the ear.