Recent Changes in Gold Mining 
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Log Washers 
Perhaps the most important change to be noted in gold 
mining practice in North Carolina is the introduction of log 
washers in treating many of the saprolitic ores that are found 
quite abundantly throughout many portions of the State. 
The old principle of the log washer cannot be patented, but 
the machines that are now being used, known as modern pul- 
verizing concentrating machines, possess many mechanical 
improvements that adapted them to the work that they are 
called upon to do. 
Each separate unit of these machines consists of two 
improved log washers running at high enough speed to read- 
ily disintegrate the soft material and so mix the clay into a 
fine pulp with water that the gold can readily settle to the 
bottom. Each machine is essentially a long trough or boiler 
plate containing a revolving cylinder fitted with heavy white 
iron arms set spirally so that the ore, while being hammered 
fine, is gradually worked to the discharge end. At the end 
of the first washer, the larger, hard and nearly barren quartz 
stones are removed by a revolving screen and belt conveyor, 
this being done to save wear and power in the second washer, 
where the gravel is still further reduced iu size and more gold 
settles out. The gravel that remains after passing the second 
washer is removed by a finer screen and the chief pulp, free 
from stones, passes from the riffled sluices about three feet 
wide and of varying lengths, which contains mercury to 
amalgamate and save any free gold that does not settle in the 
machine. 
The steel troughs are about 2 feet wide by 2]4 feet deep, 
the first being 18 feet long and the second 12 feet, with a 
semicircular bottom and a flat wood top. The revolving cyl- 
inder is made of an 8-inch steam pipe carried upon a heavy 
steel shaft, passing through stuffing boxes at the ends of the 
trough. Wrought iron bars reach through this pipe cross- 
wise and project about 3 inches on each side to form legs to 
which 8*4 inch cast iron arms are bolted to take all the wear. 
There is about 4 inch clearance between these arms and the 
