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animals bore but little resemblance to those now living. 

 Mesozoic time or the period known as middle life when 

 the creatures began to be something like ours. The 

 Cenozoic time or recent life, and the present time or 

 that in which we live, are divided into 

 Ages, such as Silurian or mollusks, Devonian or fishes, 

 Carboniferous or the age of coal plants. From the 

 pictures we see and the histories we read, those crea- 

 tures of past ages must have been very curious and fe- 

 rocious. The age of reptiles was the most extensive, 

 and it was during that time that animals began to re- 

 semble those now in existence. The further in the 

 earth the fossil is found the less resemblance it bears. 



Petrifaction or hardening into stone is more likely 

 to take place when the objects are buried near or under 

 water. Wood bears exactly the same appearance that 

 it did previous to the change. All the fibers and wrin- 

 kles upon the bark are vividly show. Such specimens 

 are very desirable for cabinets. The mineral wealth 

 and distribution of the world is beyond calculation, 

 and the varieties many. Some are rare and beautiful, 

 others abundant and useful. 



The mineral wealth of the United States is enormous. 

 Those found in most abundance are gold, silver, copper, 

 iron, lead zinc and platenum, all of which are useful in 

 some manner. Gold is found chiefly in California, in 

 this section of country, although new and extensive 

 deposits are found in other localities. It is used in the 

 making of jewelry, ornaments and money. Silver is 

 put to much the same use. The main copper regions 

 are in the vicinity of lake Superior, where it is very 

 abundant. Its uses are many and well known. Iron 



