Was watching ancient impossible's and one of the thing's they showed was how the Romans mined silver. Basically they used a water mill but instead of using water flow to move the mill they used slave's to move the water out of the mines. This meant that the slave's never saw day light and worked under ground until death. In Spain there is a mine where 8 giant wheel's were discovered and it seemed that the slave's would walk on top of these wheel's like a mouse. So slave's would hit the dirt or rock.. whatever to extract the dirt, they would then transfer the dirt into one of the mill's which would then deliver the water that has the dirt inside, up to 100 feet above ground. So 8 level's of depth and each wheel is placed on each level. And here we are with 20 dollar an ounce =( Worse part is the slave's ended up dying 12-18 month's later because of the toxic nature. Once the slave's died there body's would be left there.
