My office is on the fourth floor of a Class 2 building (i.e., constructed to withstand fairly substantial earthquakes, tornadoes and other super-stressors). I was sitting at my desk, talking to the Major who was leaning over the Les Nessman wall.

I heard a loud rumble like thunder or a passing train, but constant, and then the floor and the walls started to bounce and the desk top began to vibrate. The cup of water beside my computer slopped all over the desk.

The Major said, "What is that? Is that an earthquake?"

I said, "I do believe it is."

And then it was all over.