116 PROCEEDINGS OF THE CANADIAN INSTITUTE. 



be SO termed, since the more these rocks are studied the more is one 

 impressed with the actual mysteiy that as yet veils their natural his- 

 tory from our view. There have been, indeed, many speculations on 

 these pi'oblems of foliation and cleavage, and provisional theories, 

 such as the existing state of knowledge warranted, have been ac- 

 cepted. But speculations devoid of a broad foundation of accumu- 

 lated facts, and theories that have survived their usefulness, become 

 in time pernicious encumbrances, instead of aids, to the advance of 

 science, and must yield always to more and more substantial beliefs, 

 as vigorous and intelligent investigation proceeds. 



In the working out of archean geology the theory of metamor- 

 phism has been a powerful stimulant to research and has given us 

 many valid results which entitle it to hold a place of the greatest 

 respect in the history of the science. It has, however, fallen short 

 of its aims in the two chief objects which it has ostensibly sought to 

 accomplish, viz. : ( 1 ) the formulation of a consistent and acceptable 

 account of the original character of the archean rocks ; (2) the fur- 

 nishing of a key that wrill enable ns to solve their present structural 

 complications. The great truth the theory of metamorphism has 

 established for science is the fact, that there is a metamor-phism to 

 which all rocks are susceptible ; but its attempt to find in this 

 metamorphism the complete explanation of the profound problems of 

 the old crystalline rocks, is a delusion which must sooner or later 

 be abandoned by geologists as freely as it has been firmly and gener- 

 ally believed in. It is difficult to find a definite enunciation of all 

 that the metamorphic theory of these rocks means. The general 

 proposition, however, that it endeavours to sustain is, that the 

 archean rocks were originally ordinary sedimentary sti^ata which by 

 a process of mineralogical changes or " metamorphism " have be- 

 come altered into the highly crystalline I'ocks we know to-day. 

 This proposition, which was once generally accepted, is now fasb 

 losing its hold upon geological belief, if we except, perhaps, that of 

 the consei'vative English school. The many and fundamental objec- 

 tions to the theory have never been satisfactorily reasoned away, 

 while much of the evidence in its favor is based upon assumption. I 

 do not propose to attack the metamorphic explanation of the archean 

 rocks in general, bub simply to call attention to two assumptions 

 which the theory both implies and finds support in, advancing 

 such facts as I have been able to observe, which tend to prove the 



