> In the 70's I did a 4 inch pipe 20 feet in the ground in Dallas. > Temperature was better than 0.1 C.
Over what time period? Dry ground or wet? How deep is your water table? ... Temperature in the ground is a skin-depth problem. Lower frequencies will go deeper. Next time somebody digs a hole like that, it would be fun to put a string of thermometers in it. Goodies from google: http://www.builditsolar.com/Projects/Cooling/EarthTemperatures.htm http://topex.ucsd.edu/geodynamics/HW3_2011_presentations/C_wine_cellar.pdf -- These are my opinions. I hate spam. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
