Back in 76' after completing military basic training and technical school, I was sent to Eielson AFB up near Fairbanks Alaska. The room I was assigned to in the barracks had a metal bunk bed, although I was the only guy in the room. I had only been there about 2 or 3 days, didn't know anybody yet to hang out with, so one evening, I went to the base movie theater as The Exorcist was playing.
I get back and after a bit I hit the rack. Around 0300 or so, I was awakened by my bed jumping up & down. I was still 1/2 asleep, groggy, and initially thought it must be due to a large aircraft taking off, as my barracks were close to the flight line. But then I thought that there's no way an airplane is gonna make my bed jump. Then, I remembered seeing the Exorcist the night before and started thinking, Holy Sh*t, I've got something evil my room causing my bed to jump up and down. Then I heard a guy walking down the hallway yelling "Earthquake". Whew, I've never been so happy to be in an earthquake, lol.
It was only a 4.5 on the Richter scale, but it was enough to pick up both the bed and me & bounce us up & down a bit. I can't even fathom what a quake over 7 would do. Gotta remember, that scale isn't linear. Although a quake could only be a couple tenths higher than another, that quake could be twice as strong, so can't just go by the decimal point numbers as the jump in intensity & severity can be much stronger than what we think the numbers represent.
