Measuring the Earth with a Stick: Science As I've Seen It

Steve Pitt is a Toronto-based freelance writer and an award-winning journalist. He has written many young adult and children's books, including Day of the Flying Fox: The True Story of World War II Pilot Charley Fox.

Just over 2200 years ago, a holidaying Greek named Eratosthenes happened
to look down an Egyptian well at high noon and notice that the sun was
looking back at him. Eratosthenes realized that he had accidentally
discovered the one day a year when the sun passed directly over this
particular spot. Exactly one year later, Eratosthenes used a small
sticklike astronomer’s instrument called a gnomon to measure the
sun’s attitude in the sky from another well in Alexandria. The gnomon
registered an angle of seven degrees. By multiplying the angle of the
sun against the distance between the two wells, Eratosthenes was able to
accurately calculate the circumference of the Earth in an era when most
people still thought the Earth was flat.

Bob McDonald’s book takes its title from this fascinating story. The
general content of the volume reflects the spirit of Eratosthenes: you
do not have to have a multimillion-dollar laboratory to be a scientist;
all it takes is an inquiring mind and some imagination. McDonald asks
questions like: Why do people vomit when they feel dizzy? Why doesn’t
the crew of the Starship Enterprise get plastered to the bulkheads when
Captain Picard says “Engage!”? How long does it take a drop of
rainwater falling in Georgian Bay to travel to the Atlantic Ocean? What
famous weather phenomenon did plumbing engineers copy to give you a
better toilet? This is not a book for those who want quick facts to
quirky questions; rather, it’s a guide to how to see the world with a
scientific eye.

Although McDonald has spent nearly two decades explaining science to
millions of Canadians, he manages to approach each topic with a sense of
new wonder. He even confesses to a temporary crisis of faith when modern
medicine failed to save his best friend from cancer. McDonald is both
exuberant about humanity’s accomplishments and humble about our
limitations. The result is a book with more good reading than even
Eratosthenes could shake a stick at.