The “long corridor” referred to is actually a mechanical transmission line in the form of a helical spring. Compressional waves in the audiofrequency range are sent down the spring by an electromechanical driver and received at the far end by an electromechanical pick‐up. Reflection occurs at each terminal allowing standing waves to build up. Oscillograms have been obtained for frequencies below 100 cycles, showing the discontinuous nature of the “reverberation” which is produced in such a “long corridor.” Eyring's mechanism, using image sources, is shown to fail to explain the oscillograms. A new mechanism is presented which seems to explain all cases, including that of non‐normal modes.