Well, I grew up in the Bay Area, so I've been in earthquakes before.
I couldn't help but be impressed by the magnitude of the earthquake.
My mother-in-law had to stop skipping for exercise. It registered seven on the Richter scale.
If one introduces the concept of energy of an earthquake then that is a theoretically derived quantity.
I'm glad to see the press now referring to the open-ended Richter scale.
Lately there have been complaints that the use of the magnitude scale is confusing, or at least the reporting of magnitudes in the newspapers 'confuses the public.
I repeatedly have to correct this belief. In a sense, magnitude involves steps of 10 because every increase of one magnitude represents a tenfold amplification of the ground motion. But there is no 'scale of 10' in the sense of an upper limit.
For some days, people thought that India was shaking. But there are always tremors when a great tree falls.
There is another common misapprehension that the magnitude scale is itself some kind of instrument or apparatus. Visitors will frequently ask to 'see the scale.'
I suggested that we might compare earthquakes in terms of the measured amplitudes recorded at these stations, with an appropriate correction for distance.
What emerged, of course, was that the magnitude scale presupposed that all earthquakes were alike except for a constant scaling factor. And this proved to be closer to the truth than we expected.
Incidentally, the usual designation of the magnitude scale to my name does less than justice to the great part that Dr. Gutenberg played in extending the scale to apply to earthquakes in all parts of the world.
[In plotting earthquake measurements] the range between the largest and smallest magnitudes seemed unmanageably large. Dr. Beno Gutenberg then made the natural suggestion to plot the amplitudes logarithmically.
If the Richter scale could measure human calamities, the loss of a child would register a ten.
