A Working Dredge

A Working Dredge. The Ultimate Gold Mining Machine. The dredge is a huge but simple machine for mining an ancient river bed for gold. It is an expensive, powerful improvement on the shovel and rocker box. , Miners used to call the dredge a "goose"---and for good reason. The dredge is "fed" at the front end, "digests" the soil inside the dredge---keeping the gold it collects- then expelling the excess soil out the back., The dredge was guided by a series of cables and winches and powered by Fremont Powerhouse using a 19-mile extension cord., "Feeding," or excavation was done at the front end of the dredge using 72 one ton buckets mounted on a huge boom, called a bucket line. The buckets gouged into the soil and carried the loose rock into the inside of the dredge., Steel cylinders separated the material by size. The smaller material went deeper into the dredge, and into a series of sluices that acted like filters., The material was then dumped into a hopper, which fed the material into a trommel, a rotating screen. Anything that went through the screen probably had gold in it, and this material---a mixture of water, gold, dirt, and small gravel called slurry---went to the riffle boxes, where it was treated to extract the gold., Anything too large to go through the screen of the trommel went into the tailing stacker, which spewed it out of the back of the dredge as tailings.