| 1635 |
Freshwater, Isle of Wight, England
|
|
Robert Hooke born.
In 1676, the English physicist Robert Hooke published
The True Theory of Elasticity or Springiness
with the anagram CEIIOSSOTTUU on the title page.
The solution to the puzzle is "ut tensio, sic vis" or
"as the extension, so is the force."
Today we state this as "stress is proportional to strain"
and call this Hooke's Law.
This is the first fundamental mathematical formulation
in modern Seismology.
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| 1969 |
China
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7.3 |
40th Anniversary
The workers of the Tientsin zoo began participating in
earthquake forecasting in 1968.
On the morning of July 18, 1969, they discovered that
unusual behavior in many kinds of
animals was arousing attention (the swans abruptly
left the water, a Manchurian tiger stopped pacing
in his cage, a Tibetan yak collapsed,
and a panda held its head in its paws and moaned).
After collecting these reports they realized that,
as well as other factors that might have caused this
unusual behavior, it might be a precursor to an
earthquake.
They felt it was timely to make a report to the
city's Earthquake Office. At noon of that day,
a magnitude 7.3 earthquake occurred at Pohai.
Abridged from Earthquake Information Bulletin, Volume 10, Number 2.
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U.S. Department of the Interior | U.S. Geological Survey