An interesting patent I found.

[Marconi]

I saw a video on YouTube about this subject, and here is an old patent I found interesting on Google Patents Website. The are a bunch of such related old patents intended for boring holes and tunnels in the Earth without the traditional methods of today being used.

Instead they melt the Earth into a liquid and gas using this and other devices, and, then they inject the material they removed, under pressure, laterally into the adjacent porous Earth all around the hole.

https://www.google.com/patents/US18...a=X&ei=Eh6IU6fnCbPQsQT-uYHwAg&ved=0CDUQ6AEwAA

Here is the YouTube video:
https://www.youtube.com/watch?v=QUZJM_bgT0o

 

[W5LZ]

Interesting idea but not very practical at this point (if ever). How would you contain the generated heat so that it doesn't destroy your drilling machine? Not to mention the radiation. The idea has been around for quite some time in science fiction...
- 'Doc

 

[C2]

A welding torch usually has a brass nozzle and it emits enough heat to melt steel, without melting itself.

 

[KD2GOE]

Interesting idea but not very practical at this point (if ever). How would you contain the generated heat so that it doesn't destroy your drilling machine? Not to mention the radiation. The idea has been around for quite some time in science fiction...
- 'Doc

yeah the amount of radiation would be a huge door stop.. and what I don't get is where are they putting all the material? there is no way your going to take all that and glass the walls with it, plus the amount of gas released would be huge.. and if they hit water well its all over then the thermal shock to the cutter and the steam release would damage every thing...

A welding torch usually has a brass nozzle and it emits enough heat to melt steel, without melting itself.

yes I have been cutting steel for 10 years running CNC ox fuel cutting parts to near net..
cutting 10" of steel and the tips are only brass.. no outside cooling