Pi me a River

Alex Bellos discusses how the Incans used knots in string (Quipu) to record numbers.Check out Brilliant (get 20% off their premium service): https://brillian...

How the length (and sinuosity) of rivers relates to Pi - featuring Dr James Grime.

More on Pi from Numberphile: http://bit.ly/PiNumberphile

The paper in Science (abstract): http://bit.ly/1m1j79B

James Grime: http://singingbanana.com