270 Mr. Vivian on the Process of Amalgamation, S^c. [April, 



each wheel works two barrels. Thus the whole of the twenty 

 barrels are made to revolve by one water wheel, which is about 

 28 feet in diameter. The washing apparatus under the barrels is 

 worked by a separate water wheel. Every part of the ma- 

 chinery is carefully attended to, and kept in the very best order. 



1 shall conclude by a general recapitulation of the power of 

 the work, and the extent of the operations : — 



The three buildings just described, with one or two of a 

 smaller description that are contiguous to them, contain the 

 following apparatus. 



A large ore house. 



12 calcining furnaces arranged in three sets, with a charging 

 floor and salt magazine to each. 



2 coarse riddles. 

 2 fine riddles. 

 14 mills. 



20 amalgamation barrels. 



4 mercury distiUing furnaces. 



4 washing vats. 



The quantity of ore operated on annually amounts to about 

 3000 tons ; and its contents in fine silver may be estimated at 

 from 28,000 to 29,000 marks. . 



The annual consumption of mercury is calculated at 25 cwt. 

 which will be in proportion to the silver obtained as about I to 5, 

 as mentioned by Humboldt. The mercury used is brought from 

 Prague, and is probably from the mines at Idria. 



The salt employed, in the proportion of 10 per cent, on the 

 quantity of ore amalgamated, may be taken at 300 tons. It is 

 obtained from the Saxon salt-works at Arten. 



The consumption of iron in the barrels is from three to four 

 tons per annum. 



The quantity of the various substances used as fuel, Lampadius 

 calculated, in 1802, to be equal to 5-5- cubic feet of charcoal to 

 each quintal of ore ; and the amount of wages on 100 quintals 

 of ore at 17^ rix-dollars. I do not recollect having seen any 

 calculation of the total cost per ton of ore, incurred in extracting 

 the silver by mercury ; but, I believe, the charges are nearly the 

 same as in smelting. The chief advantage of amalgamation at 

 Freyberg is the saving of fuel ; for if all the ores of the district 

 were smelted, the quantity of charcoal required would be so great 

 that the price of that article would necessarily advance. 



I have thus I believe noticed the most material points relating 

 to the Freyberg amalgamation-work, and the operations carried 

 on therein. I have only again to repeat, that 1 shall feel truly 

 gratified if these remarks should prove of use to your friends 

 engaged in mining speculation on the other side of the Atlantic. 

 Should you conceive that any further information I ean give 

 may be of service, I beg you will freely command me. 



