18-10-2016 15:08 via scientificamerican.com

The Grand Canyon Puts You in Touch with Time - Scientific American - Scientific American

Scientific American
The Grand Canyon Puts You in Touch with Time - Scientific American
Scientific American
The mantra issued by the guides was as clear as the silty Colorado River was opaque: “If you're hot, you're stupid.” And so I spent most of my waking hours on ...and more »
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