Mercalli intensity scale
The Mercalli intensity scale is, in modified form, still used. Unlike the Richter magnitude scale, which measures the energy released by an earthquake, the Mercalli intensity scale measures the effects of an earthquake on structures and people. It is poorly suited for measuring earthquakes in sparsely populated areas but useful for comparing damage done by various tremors and historical earthquakes, and for earthquake engineering. The scale currently in use assigns indices ranging from I ("Not felt, except by a few under favorable conditions"), to XII ("Damage total; objects thrown into the air").