182G.]. Discovery of the Province of Minat Geraes. 397 



nnd husbandry being more suitable to small capitaU than mining, the inhabitants 

 naturally choose the former. 



It ha[)pens in all the mines, that in washing the eartli or piercing a mountain, 

 large parcels of filons are found, which are also termed batata from their 

 existing singly. 



They seem to be parts of large filons, and to have been separated by some 

 revolution of the globe, such revolutions being still evident in the internal 

 arrangement of some mountains of the third order. 



TJie methods employed for the extraction of gold are the offspring of necessity 

 and experience : some of the negroes put in practice the rude manner of 

 mining followed at Rio de Pernio. The crooked policy of Portugal never 

 permitted the introduction of scientific and learned persons into Brazil, and 

 least of all such as were foreigners, none of whom could enter into the province 

 of Minas Geraes except by an express decree, which usually accorded the 

 permission only to ignorant people, and to these merely for a limited period. 

 No other means are employed in the mines for extracting gold but the humid 

 way.* 



When it is intended to extract gold from filons or batatas, it is always 

 necessary to reduce the stone to powder ; this is invariably produced by means 

 of a pestle-engine put into motion by water, and the stone-powder is treated as 

 the cascalho of the preceding note, except that at the end of the little channel 

 or canoa, they apply pieces of woollen-cloth, for the purpose of receiving in its 

 nap the fine gold which the water brings off with it. 



In no part of the province is quicksilver used for mining gold, not only 

 because the advantage it possesses over water is unknown there, but because it 

 is very dear, owing to the duty it pays and the carriage. There are, however, 

 many places producing bituminous mercury, in which the petrol does not 

 prevent the action of quicksilver on gold. 



All the arts of mining different from those above-mentioned are unknown in 

 the province of Minas Geraes — so much so, that there are lavras extremely 

 rich which are reputed impossible to work, because they filter a great deal of 

 water. The knowledge of pumps has not jet reached there, nor the method 

 of stopping the earth when it has not consistency enough to support the mine. 

 Motives of this kind have caused very extensive lavras to be abandoned. 



It is, indeed, impossible to determine the places in Minas Geraes that are 

 richest in gold, but they present themselves very distinctly to the traveller ; 

 being the highest and bulkiest mountains, and all the rivers. 



In short, the diamond district is pretty well furnished with gold ; but it has 

 very few filons and formations ; however, in all the rivers and brooks, which are 

 very numerous, it abounds in cascalho. The sands of Scrro contain much gold, 

 whilst the granite mountains have none, unless they have some stratum of 

 other stone. Experience has proved that granite is not a mineralization 

 of gold. 



* The cascalho is dissolved in water, and they let it flow through wide canals which 

 have very little declivity. AVater impels all substances lighter than gold, which gravitates 

 to the bed of the canal, aided by tlie agitation the negroes give to it in turning those 

 substances which lodge at the bottom of the channel ; when, during upwards of twelve 

 hours, they have stirred a considerable quantity of cascalho, they cease throwing fresh 

 cascalho in the channel, and begin to move what is deposited, and take oflf tlie stones ; 

 they then wash the lightest matters and reduce it to gold mixed with emery of iron. 

 This is brought to a smaller channel called canoa, and is there treated with pure waters 

 till it is reduced to the least quantity of emery possible, and when in this state, they 

 jjcrform the operation of the batea — that is, a cone of wood, having a basis of three feet 

 and an axis of three inches, and hollow in the interior, is employed in the following 

 manner : — 



A man puts a portion of the residue of the muiing into the cone equal to the foiurth 

 part of its capacity, and fills it with water ; he shakes his emery, giving a composed 

 motion to the batea, in such'a manner that gold gravitates to the summit of the cone, or 

 bottom of the batea. The earth is taken off by the upper part, he continumg the 

 motion till he has thoroughly purified it from dross ; the particles of iron are then taken 

 off by a loadstone, and gold is gathered. 



