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mended to those who are desirous to know any 

 thing of minerals. 



PIECES of rocks, with the names of the pla- 

 ces from whence they came, would be always 

 interesting, as we are unacquainted whether 

 many islands, head-lands, &c. are granite, lime- 

 stone, or volcanic. Collections of rocks, with 

 particulars concerning them, are highly desir- 

 able, in order to determine the relative con- 

 nection of mountains, islands, &c. 



THE soil at the bottoms of streams or rivers, 

 if gravel, generally contains interesting sub- 

 jects. In India, precious stones occur in such 

 soil: in Afiica and South America, gold, pla- 

 tina, diamonds, rubies, sapphires, and topazes, 

 belong to, and are always found in gravel beds, 

 or alluvial soil, as is tin in the island of Banca. 

 Silver, lead, copper, &c, occur in veins. 

 L 



