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mended to those who are desirous to know any 
thing of minerals. 
PrgcEs 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 Africa and South America, gold, pla- 
tina, diamonds, rubies, sapphires, aud 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 
