SUBJECT>Re: Building tunnels
POSTER>T
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DATE>June 26, 1997 at 17:51:56
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<P><hr>

Most tunneling done by the drones does NOT use explosives.  They have some sort of grinding bit which drills a tunnel in any specified direction.  They also have a scooping device with which they load themselves up with the resulting gravel before transporting it out.  The explosives are used in special situations such as penetrating unusally hard rock or (perhaps) for collapsing a cliff face which contains desired minerals.<p>T

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