Next the conveyor belt carries the peanuts to a machine called a farmer's stock cleaner. This machine is made of a stack of screens that shake back and forth. The farmer's stock cleaner shakes more dirt, tiny stones, and sand from the peanuts. After the peanuts are cleaned, they are sorted by size. The sorting is done with screens that have special-sized holes. The biggest peanuts remain on top of the screens. These will be roasted in their shells, to be sold as "ballpark peanuts." You've probably eaten peanuts like this at a circus or baseball game. The smaller peanuts fall through onto a platform below. These smaller peanuts will be shelled, which means their shells will be removed. Some of them will be used to make peanut butter. Now the smaller cleaned peanuts are ready for the shelling machine. A shelling machine is a metal box that's about a foot high and about three feet long. Inside it are rolling baskets called beater baskets. Beater baskets have grates inside them, with holes about the size of peanuts without their shells. The beater baskets also have four metal bars inside, which rotate very fast - about 200 times a minute. The bars push the nuts through the holes in the grates, crushing the shells. The nuts and shells fall through the grate openings, and fans blow the shells away. Next the peanuts go into a machine called a gravity separator. It's a strange-looking contraption that's really just a set of metal platforms with fans and boxes underneath. The fans blow any pieces of leftover peanut shells into a cyclone machine - an 18 foot metal cone. The shells are collected and bagged, and later they will be sold. Tiny stones and sand fall to the bottom of the gravity separator and are discarded. The peanuts fall onto a conveyor belt. They are taken from the gravity separator to a room where they will be inspected. The peanuts are inspected first be electric eyes - beams of light that show workers if any peanuts are unhealthy or discolored. Then workers at a table check the nuts by hand. Finally, the peanuts are weighed an poured into burlap bags. A worker pushes the bags through a machine that sews the top shut. The bags are thrown down a slide and stacked onto trucks. The peanuts are on their way to the peanut butter factory.