406 



THE GEOLOGIST. 



survey there has beeu founded a startling generalization. The intellectual 

 races, if they did exist, must have lived at a distance from the ferocious animals 

 that may have occupied the seas or jungles of the ancient world, and conse- 

 quently thek remains could not have beeu found in the oi-dinary fossiliferous 

 strata. Then- dwelling-places may have been in one or more of the numerous 

 localities of our continents not yet explored, or in those immense regions of the 

 earth which are now covered by the great oceans of the globe ; and till these 

 oceans have quitted their beds, or some great convulsions have upheaved and 

 laid bare the strata above which the races in question may have lived and died, 

 we are not entitled to mamtain it as a demonstrated truth that the ancient 

 earth was under the sole dominion of the brutes that perish." I confess I do 

 not see that if intellectual races have existed prior to man, they must, as a 

 matter of necessity, have lived at a distance from the ferocious animals which 

 then peopled the world : they may have built habitations and fabricated instru- 

 ments of defence. But as we find traces neither of these nor of themselves, 

 and yet discover remams of pre-adamite animals, it must be concluded that the 

 supposed intellectual races could not have resided amongst them. Yet I agree 

 with Dr. Brewster that the generalization is hasty and unfounded ; although 

 far more probable than the former assumption, it is equally illogical. As a 

 deduction it is quite as unsound. 



As an illustration of the shutting-out of causes, if I may use such a term, 

 and the reducing of all phenomena to a few, which has rightly been said to be a 

 passion with philosophers, geologists have rather cut short the origin of springs 

 and lakes. I think that the following explanation has never received a place 

 among others : they may arise from canities running inland from below the 

 level of the sea, and terminating either upon or below the sui'face of the land, 

 thus forming either springs or lakes. According to this hypothesis the depth 

 of such a lake, for it is not said that all lakes and sprmgs are thus formed, 

 would be determined by the height of the land where the cavity or sandy 

 passage reached its surface, and the height of springs would vary in the same 

 manner ; according to the depth of the sandy cavity below the level of the sea 

 would be depth or height of lakes or springs thus formed, supposing this hy- 

 pothesis be received as correct. 



Proceeding to the third question, there is Httle difficulty in discovering that 

 after convulsions have ruptured the once orderly arrangement of the sedi- 

 mentary and igneous rocks, it is easy to perceive that mountain ranges have 

 been caused by upheaval. Tliis species of geological power produces flaws in 

 the shape of contortions and faults, which volcanic power can alone bring to 

 pass ; the gradual enlargement and diminution produced by present stratifica- 

 tion and disintegration produces regular series of rocks, wherein occur no 

 faults or other imperfections. It is probable that when the earth was formed, 

 the igneous rocks cooled so as to allow the materials of our present aqueous 

 rocks to be gradually precipitated upon them. Hence regular strata would be 

 the result, and for once assuming an hypothesis to be true, from this it must 

 be that the various mountain-ranges were called into existence after this event, 

 and that the defective strata which form them, and all whicli occur, are the 

 work of after volcanic agency. It may be thought that I here condemn myself 

 by assuming that which'oug'ht to be "^absolutely proved. But I would urge 

 that such an inference as this is in the highest degree probable, and thus may 

 be assumed as demonstrated, in which it'differs, although only in degree, yet 

 immeasurably from the inferences already noticed. 



The development of tliis latter question has lead many to theorize altogether 

 apart from experience, wlicn no real advancement of knowledge has, from the 

 nature of such a course of conduct, ensued. Logic has been separated from 

 experience ; men have arg\ied metaphysically instead of physically ; and thus. 



