Mining companies of Butte, Mont., in cooperation with Daniel Harrington, supervising engineer of the U. S. Bureau of Mines, have reduced temperatures of over 100 degrees F. in low-level workings by as much as 15 degrees, through scientific ventilation. Temperatures in the depths of the earth increase from natural causes, but added to this the Butte mines have to contend with fires which have burned for many years in worked-out regions, one continuously since 1889. These fires feed on timber and combustible sulphides, and burning laterally and vertically, have so heated the adjacent...
To continue reading:
or
Log-In
