46 GEOLOGY OF THE SECOND DISTRICT. 



observing them is from the bridge near the store. About one hundred rods below, the river 

 cuts through the same rocks again ; but the relations are somewhat changed, the limestone 

 appearing liere in the form of a dyke as it crosses the river, or rather where the river cuts 

 through it. In the adjacent fields on the west side, it spreads out, and forms the surface rock 

 over a wide area. 



This locality is no more remarkable than many others in St. Lawrence and Essex counties ; 

 yet it cannot be examined with care and attention, without forcing the observer to the conclu- 

 sion that the theory of the origin of granite applies equally well to both rocks, and that it 

 would be equally agreeable to facts and phenomena to consider the granite metamorphic as 

 limestone. In truth, if it were necessary to call one of those masses metamorphic, gi'anite 

 in this instance is the one best entitled to that appellation. It is true, that in theory, it might 

 be said that the granite was poured out over a transition limestone, and hence its position 

 beneath the former, and its change from an earthy to a crystalline rock. But this view of the 

 case would be merely theory, without a fact to support or sustain it ; it is an hypothesis, or 

 an idea, imsubstantiated by phenomena which appear at either place, and only sustained by 

 the analogy of lava which overflows indiscriminately both ancient and modern rocks. 



It may not be irrelevant, while upon this subject, to call in question the metamorpliic theory 

 as it is employed for the explanation of phenomena which are peculiar to certain rocks, or so 

 far as it brings in the exclusive agency of igneous action in producing a passage from an 

 earthy state to one which is crystalline. According to modem theory, all the sub-crystalline 

 stratified rock, termed by Boue, crystalline schists, as gneiss, mica slate, hornblende, saccha- 

 rine limestone, are rocks whicli have been altered by igneous action ; they have passed from 

 the earthy state of the sedimentary rocks, to one which is more or less crystalline. Perhaps 

 it is unnecessary to ask the question, whether this theory, in its length and breadth, is required 

 for the full and complete explanation of the phenomena exhibited by these rocks. If those 

 changes have taken place according to hypothesis, in those instances referred to, is it abso- 

 lutely essential to bring in igneous action for a rational explanation of the changes which 

 those rocks have undergone ? Admitting the original state to have been in the form of earthy 

 deposits, may we not admit the following hypothesis as one entitled to our credence, viz. that 

 the present crystalline state is due to molecular attraction, aided by water of capillarity which 

 bathes eveiy particle composing the rock ? 



That molecular power is efficient in the production of changes of an analogous kind to a 

 very great extent, seems to be agreeable to observation in many instances. The concretion- 

 ary limestones, septaria, concretions in clay beds both in the ordinary and the porcellanous 

 clays, crystals of quartz, a laminated structure in rocks, stratification in clay and gravel beds, 

 where the materials have all been thrown together without order, all take place subsequent to 

 deposition, and without the aid of heat. The forces concerned in these changes are feeble ; 

 but acting through geological eras, they exert a great amount of force in time. We may 

 conceive that every particle has not only felt the force of attraction, but has actually been 

 moved from its original place. These changes are directly proportional to the fineness of the 

 materials of which the mass is composed ; hence the aluminous rocks have the original planes 



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