It has been well established that many solutions will enter the inner ear from the middle one. In 1908 Van Rossem1 was the first to anesthetize the vestibular apparatus by applying cocaine to the middle ear. The next data on this subject were presented by Ross and Rawson2 in 1935 and 1936. They showed that procaine hydrochloride, hypertonic sodium chloride solution, diphtheria toxin, quinine, ethyl alcohol and methyl alcohol applied in the middle ear produced marked changes in the vestibular function. In the case of diphtheria toxin, hearing was completely destroyed.
Since the fenestra rotunda is the thinnest and the softest tissue between the middle and the inner ear, it has been assumed that it would be the main route for soluble substances. Fowler3 has repeatedly referred to chemicals "seeping through" the round window. He placed crystals of sodium chloride and calcium chloride on these tissues of dogs. He demonstrated