IT is now more than eighty years since Helmholtz1 gave a functional explanation of the architecture of the cochlea, and at the same time supplied a plausible physical basis for the extraordinary pitch discrimination of which the human ear is capable. Recent authorities have implicitly or explicitly rejected Helmholtz's explanation of pitch discrimination. For example, Stevens and Davis2 say ``Everything considered, then, we must conclude that the inner ear is highly damped and that this damping impairs its resolving power in the analysis of sound waves'' (p. 287); and elsewhere it is implied that the damping is critical. We cannot here consider the evidence adduced by Stevens and Davis and by others in favour of high damping of the cochlea, and must limit ourselves to the blunt statement that it is inadequate. It is the purpose of this letter to put forward evidence, independent of pitch discrimination, which unequivocally supports Helmholtz's original belief.