So far as the ancients of China are concerned, 1906 was a year of the Fire Horse - a time of grave unpredictability that comes along every six decades, and a time when all manner of strange events are inclined to occur. So to the seers and the hermits in their faraway mountain aeries such events as unrolled during the year would have come as no surprise. The rest of humankind was less well prepared, however, and were caught unawares. And what instruments we have agree that, so far as matters of the earth were concerned, 1906 was, yes, a very bad year indeed.
-Simon Winchester, A Crack In The Edge Of The World: America and the Great California Earthquake of 1906