Although no drill has been found, archaeologists have discovered beads of the same 2.5mm diameter as the holes found in the teeth, indicating the people did have the capacity to do delicate work.

BBC: Prehistoric dentistry evidence found

The men have been trapped in the desert copper-and-gold mine since an August 5 cave-in and are surviving on supplies funneled to them from above ground through three bore holes, each about 4 inches in diameter.

CNN: New video shows trapped Chilean miners in good spirits

Two bore holes -- each about 8 centimeters in diameter -- are currently being used to supply the miners.

CNN: STORY HIGHLIGHTS

The drill would use one of the three bore holes already made as a pilot and widen the diameter to about 28 inches, which officials have said is wide enough for the miners to be hoisted through.

CNN: New video shows trapped Chilean miners in good spirits

For both modes of crystal fibre, the pattern of holes is generated by stacking hollow glass tubes a millimetre or so in diameter to form a rod several centimetres thick.

ECONOMIST: A new approach to making optical fibres

Forty-two radio dishes, each 20 feet in diameter, were powered up on Oct. 11, to scope out galaxies, black holes, and--maybe, just maybe--alien civilizations.

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