OF SOUTH CAROLINA. 283 
- packing so closely as to allow the wheels to run over it, as on a road, without effect. An addition 
of this sort would do something towards removing this difficulty. 
The gold is taken from the mills at the end of each day’s work. The amalgam is placed in an iron 
retort, and the mereury driven off and collected, by placing the beak of the retort in water. The 
ores, in which 
the gold exists in a finely divided state, are also best managed in 
such a mill. Poor ores are best treated by other processes, where 
a large quantity can be ground ina short time. 
For amalgamating the gold, after grinding in the Arastre, a 
amalgam loses nearly one half in weight, by 
this process, 
Fig. 45 is the Arastre. The principal parts 
of this machine consist of heavy blocks 
of hard stone, and a bed of the same mate- 
rial. The stones are attached to the arms by 
chains, as represented in the cut; and when 
drawn round imitate, very exactly, the force 
produced by the painter’s muller and flag, 
used in grinding colors. 
It is obvious that such a machine as this 
is best adap- Rig, 46. 
ted to the I 
grinding of 
rich pyritous 
ores, where 
the gold ex- 
ists mm ml- 
nute  parti- 
cles, and is 
completely 
mixed with 
the gangue. 
The tena- 
cious, slaty 
contrivance, represented in Fig. 46, was used in St. Catharine’s 
Mill, North Carolina. The levigated ore was placed in the barrel, and a stream of water allowed 
to flow in. The central axle, with its arms, were made to revolve, by which means the whole is 
agitated. The finer particles pass off, and the gold falls down and is taken up by the mereury 
placed in the barrel. 
Another machine remains to be examined, which was once in use in South Carolina, but now 
abandoned : I mean the Tyrolese Mill, (Fig. 47.) The ore was placed in the hopper, a, from which 
it passed to the stamps, b. After being crushed by the stamps, in contact with water, it passed into 
