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A Short History of Nearly Everything.
2003. Bill Bryson. Broadway Books, NY. 544p.
While conventional histories treat wars and political leaders, this impressive
volume covers the history of matter, the Earth, physics, astronomy, geology,
biology and humanity. With a gentle, balanced, sometimes humorous style, Bill
Bryson gives us a history of the panorama of science.
He reveals curious facts about scientists and their discoveries. The pioneering
physicist, Henry Cavendish, suffered from shyness to a degree bordering on
disease. Having inherited a machine designed and built by John Michell to
determine the mass of the earth, Cavendish as his final experiment in 1797 made
that amazing measurement. Resembling an antique Nautilus weight-training
machine, the apparatus estimated the deflection of small lead spheres by 350 lb
lead spheres. This incredibly sensitive measurement required Cavendish to work
in the next room making observations peering through a peephole using a
telescope! From this he determined the gravitational constant and calculated the
mass of the earth as 6 billion trillion metric tons. (A metric ton equals 1000
kg or 2205 lb.)
Bill stands in awe of precise numeric values that make the Earth amenable to
life. As an example, if the Earth were 5% or more closer to the sun or 15% or
more further from the sun, it would be uninhabitable for complex surface life.
It could possibly support remarkable extremophiles [members of the Domain
Archaea, really primitive bacteria] that can survive very hot and very cold
conditions, very acidic or very salty, but not us.
Astonishingly, the Earth’s magnetism depends on the liquid outer core spinning.
As an electric current in a wire produces a magnetic field, our spinning core
produces our magnetic field. Because both our moon and Mars lack a liquid core,
they lack magnetic fields. In addition to helping birds navigate during
migration, magnetism deflects damaging cosmic rays into near space. Again this
protection favors life.
The origin of human life by the process of evolution proves incredibly
improbable. Bill feels privileged to be a resident of Earth. He finds its
intricacies awesome. The arbitrary human-induced extinctions of birds and large
animals on several continents alarm him.
Review written 17 February 2005
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