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 combustibility 
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. ; laliasid 
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. a 2a 
