Mount St. Helens in Washington state grumbled and steamed for weeks before she blew. One day my brother and his wife and I went to Castle Rock - the closest town to the mountain - and had lunch. Our window overlooked a small fenced pasture in which there was a horse.

This horse was agitated. It would run to the fence, neigh loudly, wheel and gallop away only to repeat it over and over, in a manner very different from the usual calling a horse does. That was one scared critter. Three days later the mountain blew.