74 



WHEREVER, there are mines, (subterraneous 

 excavations), metals of some sort or other arc 

 produced ; and it surely is not burthensome to 

 the intellect to distinguish lead ore from copper, 

 or silver from lead, or gold from iron, or dia- 

 monds from pebbles. 



PERMIT me to advise the traveller to look 

 into the book of nature, which is always open, 

 and learn what he can. A little information 

 on this head may prove highly advantageous, 

 as the wealth of nations mostly depends on 

 the produce of their mines. It is earnestly 

 to be recommended, wherever he goes, to 

 bring from thence some specimens of the 

 rocks ; and if any other present themselves, he 

 should endeavour to possess himself of them, 

 which he might examine at leisure, with the 

 blow-pipe : the use of this instrument, and the 

 mode of managing it, are fully explained in a 



