Seen from the front, you get a better view of the riffle plate or I guess you could call it a box. The black bar in the middle rotates. When it is down it holds the riffle box. When you turn it up, you can pull the riffle box with the heavies at the top of the riffles out and dump the material in a bucket to later pan. Waste material piles up near the wheels on this model. There are a number of variations on the market. There are also directions on the Internet for how to build your own. This wooden model is fairly heavy. Most people want one made of aluminum so it isn’t so heavy to carry.
The wooden pulley is connected to a crank on the bottom that is similar to a crank shaft. The shaft hits the bottom of the dry washer with each turn of the wheel and causes the riffle plate to vibrate. There is a bellows below the riffles that is hitting the frame of the riffle box with each turn of the wheel. The bellows also blows air up which helps dust to blow away- the white cloth in the riffle box actually vibrates and bounces a bit.
In Coloma, California there is a park where a fellow can pan for gold, free! Yep, on the north bank of the American River running staight through the park you can take a pan and have some fun. You cannot bring automated tools, not even hand tools. You may use your hands to dig. Even though the park is very clear about what you can and can’t do, it is a beautiful place. And, I found a tiny nugget and one placer flake, too! I’ve got photos along with all the details at the link above. Give it a try.
While traveling to Las Vegas from Superior, Arizona we crossed the Hoover Dam Bridge. What a magnificent structure. It is hard to believe that anything like that could be constructed. But, then, just look a bit to the west and you can see the new bridge (even longer and higher) that bypasses the dam. You have to admit, the United States has some fantastic builders!