430 University of California Publications. [Geology 



foliation partings produced by movement consequent iipon vol- 

 ume expansion during hydration. 



The production of the silica-carbonate rock, then, illustrates 

 an extensive ease of hydro-metamorphism, effected by solutions 

 highly charged with carbon dioxide, and carrying calcium car- 

 bonate and metallic sulphides. 



University of California, 

 May, 1906. 



