16 



Gold Mines of Georgia. 



box c in the preceding figure, which is furnished with cleats, &c. ; 

 the water is distributed over the whole plane and the working is aided 

 by the spring laths b on each side. This cannot be called an improve- 

 ment as it is liable to all the objections which apply to the pan-gura 

 or inclined plane, but especially to another which is the shape of the 

 drawer, causing the water to act very forcibly in passing from one 

 side to the other, and thus increasing the probability of the fine par- 

 ticles being carried off with it. The other machines in common use, 

 are mere modifications of those already described. For those pat- 

 ented, the "Journal of the Franklin Institute" may be consulted. An 

 arrangement tried by the author, is intended to unite the amalga- 

 mating to the gravitating process ; it is used when the assay has shewn 

 that mercury will be required to collect the minute particles. It is 

 applied in the following manner. The preparatory washing of the 

 gravel is to be effected in a revolving iron cylinder, similar to a bolter, 

 which will also cause a separation of the large gravel to be discharged 

 at the lower end. The gold and finer fragments of rock, garnets, &c. 

 that have passed through the perforations of the cylinder, are to be 

 swept over a perforated plane, the perforations being of such size as 

 as to allow the largest particles of gold to pass through into rockers, 

 on the principal of the " gum" but hinged by the edge instead of 

 being hung on gudgeons at the centre. The machine, thus far, is 

 capable of securing every particle having any appreciable gravity, but 

 if there are as many minute particles as will pay the expense of saving, 

 1 then add the amalgamator, which receives the washings from the 

 rockers and triturates them with the mercury.* There are not many 

 deposit mines requiring the aid of mercury, and when used with the 

 pulverized gangue of the veins or ridge mines, the process is some 

 what different ; heat, salt, or acid is then introduced with the ore, 

 and a limited measure of water. The Mexican method is given in 

 the Journal before alluded to. A mill for pulverizing, and a furnace 

 for heating the quartz, are necessary to the vein mines. 



* The drawings are in the patent office, although the machine is not patented, but 

 will be as soon as opportunity offers. 



