Stock Photo: Draining mine workings by means of a battery of three pumps. The axle, B, is powered by an overshot water wheel. The cams on the axle raise and lower the piston rods by means of tappets. C is the bottom of the pipe which is encased in the basket, D. From De re metallica, by Agricola, pseudonym of Ge

Stock Photo: 1746-1921 Draining mine workings by means of a battery of three pumps. The axle, B, is powered by an overshot water wheel. The cams on the axle raise and lower the piston rods by means of tappets. C is the bottom of the pipe which is encased in the basket, D. From De re metallica, by Agricola, pseudonym of Ge