And since denizens of the San Francisco bay area like to describe these earthquake things, I thought it was both a roller and a shaker.
My recollection is it went:
Pop! Whump-whump-(whump)...BANG!!! GABUMP!GaBump!gabump-bump-bump-wump-wump-wump. [Followed by the stillness of the earth and the continued creaking of the house and ringing of the wind chimes in the doorway of the hall to the laundry room.]
