Association of American Geologists and Naturalists. 245 



Should we admit that the agents of combustion, which have 

 been supposed in this statement to act first upon the combustible 

 elements at the surface, exist also in the profound interior, so as 

 to produce combustion there ; or to combine in any other manner, 

 so as to evolve heat, then we are supplied with another igniting 

 power in the interior, in addition to the thermo and voltaic elec- 

 trical. Nor need we suppose either of these powers ever to 

 become extinct. Electricity, excited as suggested above, may 

 flow on, without limit of time, and occasionally with paroxysmal 

 intensity ; the combustible elements, which, by burning or by 

 other similar chemical action, have lost their cornbustibility 

 may, by the power of galvanic decomposition and the chemical 

 agency of hydrogen, be evolved again and be thus restored to 

 their original combustibility. In this manner, the elements of 

 water may be combined by combustion to produce that fluid, and 

 this may be decomposed anew, so as to evolve the elements again 

 in pristine energy. So, potassium and sodium and the metallic 

 bases of the earths may be evolved, and the chlorides, iodides, 

 bromides, and fluorides, may be alternately decomposed and re- 

 composed, and the more combustible elements brought into com- 

 bustion by contact with water or with oxygen in a state of free- 

 dom or with chlorine, or other similar agents, may serve as match- 

 es or as kindlers to ignite those that are more tardy in burning, 

 until the most energetic effects of combustion are added to those 

 of electricity, and thus an eternal circle of causes is establish- 

 ed — causes whose existence and operation are experimentally 

 proved, since they are now always at our command, to pro- 

 duce on the surface of the earth exactly such effects as we have 

 supposed it possible that they may produce in the interior of the 

 planet. 



As a thermo and galvano-electric power is a permanent princi- 

 ple in nature, ever active and ceaselessly regenerated, with its at- 

 tendant decompositions and combustions, we can no longer hesi- 

 tate to admit its agency as the great cause of the internal heat of 

 our planet; nor is it improbable, that the solar orb and all the 

 central suns of other worlds derive their perpetual radiance of 

 heat and light from a similar cause, although that cause, like all 

 other final causes in our philosophy, is inscrutible to our minds, 

 and must be referred ultimately to the agency of the Creator, in 

 immediate and energetic action. 



