Another such phenomenon is the so-called earthquake-sky, which the present writer has had several occasions to witness. It consists of a peculiar, almost terrifying, intense discoloration of the sky, and, to those acquainted with it, is a sure sign of an imminent or actual earthquake somewhere in the corresponding region of the earth. This phenomenon teaches us that the change in the earth's condition which results in a violent movement of her crust, involves a region of her organism far greater than the subterranean layers where the cause of the purely mechanical events is usually believed to reside.⁶