The Flot-Tech flotation machine consists of two tanks of water connected by an electric pump. The pump pulls water from one tank and pushes it into and up through the second tank where the soil sample is located. The flowing water lifts carbonized plant remains out of the soil and carries them over a sluice into a collection screen. Heavy objects, like artifacts, rocks, and large pieces of charcoal are collected in a second screen. The flotation process was pioneered in the 1960s and has helped revolutionize the study of plant use at archaeology sites.