228 Natural Hiftory of Gold. [Book VI; 



been computed to be leis u.an the one hundred ancl 

 thirty-four thoufandth part of an inch, and the degree 

 of extenfibility has been carried Hill farther. In ordi- 

 nary gold-leaf, which is made by hammering plates of 

 gold between flcins, or animal membranes, a grain is 

 made to cover fifty-fix fquare inches and a quarter. 

 In this ftate its furface is fo -great that it may be made 

 to float in the air with the flighteft agitation, and its 

 thicknefs is not more than the two hundred and eighty- 

 two thoufandth part of an inch. 



Gold is produced by nature very plentifully. There 

 is much of it in Brazil, in the Spanifh E?ft and Weft 

 Indies, on the coaft of Africa, and in Upper Hungary, 

 where the mines have remained unexhaufted for ten 

 centuries. Peru and Mexico abound with gold in a 

 variety of forms. It is met with in the fands of rivers 

 and mountains. Some rivers in France, as well as 

 in this country, contain gold in their fand. It is alfo 

 found in the fiflures of rocks, imbedded in hard 

 Hones. Pieces of gold of feveral ounces, and even 

 pounds weight, are fometimes found, but in general 

 it is diffufed in fo fmall portions, and through fo large 

 a quantity of fand, that the trouble of extracting it 

 is fcarce.y repaid by the gains. In all parts of the 

 world, particularly in Europe, gold is moft frequently 

 found in flrata of fand, in which it feems to have been 

 depofited by water. Gold mines were once wrought 

 in Scotland, and it appears upon record that forty-eight 

 thoufand pounds fteriing of this gold was coined in 

 the Scotch mint. It is now a general opinion among 

 mineralogifts, that there are fcarcely any fands entirely 

 free from gold, and which, by accurate examination, 

 cannot be made to afford more or lefs of that fub- 

 flance. 



Confidering that gold has no attraction for fulphur, 



and 



