sloping right to the Saronic gulf, there issued thence a deep rumbling sound, as it were an earthquake, a fearsome noise, and the horses reared their heads and pricked their ears, while we were filled with wild alarm to know whence came the sound; when, as we gazed toward the wave-beat shore, a wave tremendous we beheld towering to the skies, so that from our view the cliffs of Scirori vanished, for it hid the isthmus and the rock of Asclepius;