That's half the thickness of a sheet of paper.

BBC: Getting the measure of dark energy

Standing silently but amiably to one side, he would unbolt the magic boxes, hold the ropes, demonstrate the emptiness of beakers and pots, confirm the thickness of a sheet of glass before a near-naked girl would climb into a magic box and pass straight through it!

ECONOMIST: Ali Bongo | The

About 14 million years ago, a period of climate change caused the formation of the Antarctic ice sheet, which averages one mile in thickness and gets up to three miles thick in some parts.

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