322 GEOLOGY. 



Observe how the mechanical, chemical, and vital forces 

 were in operation here. The carbon of the air was made 

 a part of the wood in the enormous vegetation of the 

 Carboniferous era, through the vital and chemical action 

 of the leaves (81, Part II.). Then, by chemical and 

 mechanical operations together, this wood was accumu- 

 lated under strata and changed into coal. The same op- 

 erations are going on now, but not to any thing like the 

 extent that they did in the Coal-making age. For ages, 

 then, we may say, the coal which mankind are now burn- 

 ing was stowed away in the atmosphere, unseen in its 

 gaseous union with oxygen, and at the proper time it 

 was brought down, and stowed in solid form in the bow- 

 els of the earth, ready for man's use. 



438. Circulation of Matter. You see that by the forces 

 which I have mentioned a large portion of the matter in 

 the world is in constant motion, water being the chief, 

 but not the only agent by which the motion is kept up. 

 More of it was in circulation in former ages, when the 

 continents were in process of formation, than there is 

 now, when they are, in a certain sense, completed. There 

 is enough of it now remaining quiet to give " the founda- 

 tions of the earth" stability, and the great object of the 

 present circulation of matter is to keep up the operations 

 necessary to make the earth a fit habitation for man. 



439. Exertion of Creative Power. It is the notion of 

 some that the Creator put a certain amount of matter 

 into this ball that we call earth, and then left it, under 

 the operation of certain laws or tendencies, to work out 

 all the results which we see. In other words, the ma- 

 chinery, mechanical, chemical, and vital, was wound up, 

 so to speak, in the beginning, and has not been touched 

 since by the creative hand. That there have been no 

 additions to the matter in this world since it was first 

 launched into space is probably true ; but that creative 

 power has often been exercised in giving new properties 

 and tendencies to matter there is the most decisive evi- 



