Charles Darwin’s Rocks of Ages
On his early travels across the world it was geology that struck Charles Darwin’s interest, not biology.
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Charles Darwin experienced what he recalled as one of the most significant events of his five year voyage aboard HMS Beagle on 20 February 1835: his first earthquake. He was resting from specimen gathering in woods near the southern Chilean town of Valdivia when the quake:
Came on suddenly and lasted two minutes (but appeared much longer) … I can compare it to skating on very thin ice or to the motion of a ship in a little cross ripple … a breeze moved the trees, I felt the earth tremble.
Darwin rushed back into Valdivia where what most struck him was the ‘horror pictured in the faces of all the inhabitants’. He decided that: ‘An earthquake like this at once destroys the oldest associations; the world, the very emblem of all that is solid, moves beneath our feet like a crust over a fluid.’ Further up the coast, at Concepción, Darwin experienced two sharp aftershocks as apparently solid ground beneath his feet transformed into ‘a partially elastic body over a fluid in motion’.