4o6 Queries and Ohservailons relating to 



of chemical affinity: but it seems exceedingly difficult to admit, 

 with the Neptunian geologists, that all the substances which com- 

 pose rocks and strata were coexistent in the same fluid, and that 

 this fluid after it iiad deposited only a small part of its contents 

 was capable of supporting animal life. 



The succession of, aqueous and igneous eruptions would ac- 

 count for the alternation of volcanic rocks with others of aquatic 

 formation. The occurrence of obsidian and basalt with clay 

 and sand^tone mav be parts of the same series of pbaenomenaj 

 and thus the two opposing systems of Werner and Hutton may 

 both be true to a certain extent, and agree with existing facts. 

 However vast these operations may appear, thev sink into insig- 

 nificance, compared with the bulk of our planet itself. If a 

 three-feet globe were to contain within it a fluid capable of ac- 

 quiring consistence by exposure to the air, and were this fluid 

 from time to time to exude through minute cracks or punctures, 

 and form over different parts of the surface successive coats of 

 varnish whose aggregate thickness was less than that of a wafer, 

 this would be a greater change with respect to tiic artificial 

 globe, than the formation of all the rocks and strata with respect 

 to the earth. And the numerous dislocations and fractures, by 

 subsidence or other causes, are no more in comparison to the 

 magnitude of the earth, than the cracks or inequalities of this 

 superficial varnish would be to a globe of that diameter. 



I have already stated my opinion *, that all the secondary 

 strata are local formations originally deposited in detached lakes, 

 which have covered part of our present continents when the sea 

 began to retire ; for the inequalities of tlie surface must have 

 been greater before the deposition of the upper strata had filled up 

 the lower concavities. In proportion to the quantity of matter 

 tjirown from the interior of the earth might be the subsidence 

 of the surface in other parts ; and as the waters retired further 

 from our present continents, the size of the lakes which then 

 covered them would be diminished ; but their number would be 

 increased, and also the number of local, or independent, forma- 

 tions of strata. Similar causes still continuing to operate in 

 different situations, might produce general features of agreement 

 amidst the diveraity of rock formations which were taking place. 

 Now this is precisely what we observe in comparing tlie succes- 

 sion of rocks in distant ccinitries. We have no sufficient rea- 

 son to believe that those rocks which are called primitive, are in 

 reality the original coat of the nucleus of our planet, nor that 

 the similar rocks of distant regions are contemporaneous ; the 

 great diversity which prevails both in their order of succession 

 and composition appears to oppose the theory of universal for- 



* Chapter X. 



mrviions. 



