Keil/mu's TAe&ry of Grange, ^e. 37^ 



in: the original mass, are not the same in quantity and quality 

 as in the products, this, in my opinion, is a decisive proof against 

 the correctness of the liyiJothesis. It is a mistake to suppose 

 that it is possible to substitute speculation for the natural re- 

 lations which science has not explained, and the mistake be- 

 comes more important wlien such speculation supposes some- 

 thing which is in opposition to what is taught by the funda- 

 mental doctrines of science. Each step beyond the certain 

 boundaries of science is nothing else than a fiction which is 

 usually proved to be incorrect by scientific investigation. In 

 the treatment of such subjects of an investigation as cannot be 

 explained in the present state of science, a greater degree of 

 scientific acuteness of perception consists in perfectly under- 

 standing what cannot be explained, than in anticipating science 

 by suppositions. We cannot advance farther than to compre- 

 hend what can be understood, and clearly to be aware of what 

 cannot be understood. '''^ 



In regard to the greenstone masses with the included pieces' 

 of gneiss, this can only be explained under the so-called Plu- 

 tonian theory, for which the presence of our existing volca- 

 nos, the universal regularly increasing heat of the earth to- 

 wards its interior, as well as the still continued shrinking of 

 the crust of the earth, that is, the gradual elevation of some 

 regions and the sinking of others, afix)rd so many remarkable 

 proofs. Besides, this new attempt at explaining is not requi- 

 site, even although it did not bring forth scientific proofs of 

 its incorrectness ; for if greenstone had been pushed up from 

 below in a liquid state, granite, syenite, and porphyi-y must 

 have been so likewise. Supposing that the latter present phe- 

 nomena, in the superimposed rocks of a different origin, which 

 seem to defy a mechanical explanation ; still this impossibility, 

 in examining tlie mechanical details, does not cany with it 

 any proof against the fundamental idea, that they came from 

 below in a liquid state. Who can take it upon himself to ex- 

 plain the formation of the highly fantastic forms of the snow- 

 fields .'' asks Sefstrom, in his admirable examination of the ori- 

 gin of boulders. That snowfalls and storms are the principal 

 agents we all know. The circumstances which opei'ate in the 



