IO THE CHICAGO ACADEMY OF SCIENCES. 



crystal, and the magnesia, potash, soda, iron and other sub- 

 stances could form various minerals; until that which was so 

 displeasing would be resolved into the most highly prized of 

 objects. 



All of these minerals have been made artificially, so the 

 fancy is legitimate, and it may illustrate the fact that though 

 the minerals of the region at first sight are unattractive, they 

 do in reality contain much to reward the student. They have 

 beauty as well as practical and scientific value. 



