108 DISPOSITIONS, FRACTURES AND 



of substances whose power we have in other cases 

 witnessed. It is equally certain that the veins of trap 

 are connected with deep-seated masses of the same 

 substances; and it is easy to conceive that these may, 

 not only be themselves invisible, but that even their 

 ordinary indications, through ramifying veins attaining 

 the surface, may not be present, or are, from cicumstan- 

 ces, not to be discovered.. Thus strata may have been 

 elevated by subjacent yet invisible masses of the trap 

 rocks. 



The same reasoning applies in a still stronger 

 degree to granite, which, from the very nature of its 

 position with respect to all the strata, is often, not 

 only present, but even near at hand, when it is invisi- 

 ble. Of this, we see examples every day in granitic 

 countries; where natural sections sometimes detect 

 the presence below the surface, of masses of granite 

 which do not reach it; or when the presence of con- 

 tinuous massess of this rock beneath, is indicated by 

 veins or by detached portions. 



Now in examining the junctions of the strata with 

 granite, it is found, as elsewhere more fully detailed, 

 that these are of a very irregular nature. Not only 

 are they such as to prove that the strata have not 

 been deposited on the granite in regular succession, 

 but the marks of fractures and dislocation which they 

 present, prove that the granitic rocks have been pro- 

 truded beneath them and have formed the immediately 

 acting force. Thus it may be argued, that in many 

 instances where granite cannot be traced, or where 

 we have not even any indications that should justify 

 us in believing it present, it may still be the cause of 

 the appearances under review. 



Thus far the chain of argument appears unbroken, 

 but here it terminates. It is unnecessary to pursue 



