The Interior of the Earth 



Observatory has never ceased to show exactly 

 the same temperature, 11.82 centigrade. 



But this temperature, while constant in 

 every single position, increases with the depth. 

 This increase has been observed under the most 

 varied conditions in borings, mine shafts, etc. 

 It is also manifested by the high temperature 

 of waters springing from the depths of the 

 ground. The waters of Hammam-Maskoutine in 

 Algeria leave the ground at a temperature of 

 95 centigrade, and the temperature of the Great 

 Geyser of Iceland, measured inside the funnel 

 and near the surface, mounts as high as 126 

 centigrade. As a consequence of the same 

 phenomenon water has been found in Siberia 

 unfrozen at a depth of 420 feet, under a layer of 

 ice whose temperature at the surface was 10 

 below zero. The law of the increase of tempera- 

 ture with the depth is therefore general, and the 

 very rare exceptions observed are easily ac- 

 counted for by local conditions. 



This thermic variation necessarily causes a 

 flow of heat from the hot, internal regions to the 

 cooler surface regions. Therefore the earth is 

 constantly cooling and radiates to the exterior 



125 



