Sometimes Charlie uses a crane to get loose earth out of a hole. The crane has a long boom with wheels at the tip. Cables run over the wheels. Charlie fastens a kind of bucket called a clamshell to the cables. With its mouth open, the clamshell drops down over a heap of rocks and earth. Then Charlie starts machinery that pulls up on the cable. The jaws of the clamshell squeeze together and come up with a load of earth. Now Charlie swings the whole crane around till the clamshell is hanging above a truck. He pulls a cable that opens the bucket, and the earth and stone tumble out. After the basement for a building has been dug, Charlie uses the crane for other jobs. Men hook the cables to heavy steel beams, and Charlie lifts them into position. [Illustration] No matter what he is doing, he has a lot to watch out for. He must know which of four brake pedals to use at any moment and which of four hand levers to pull. One lever works the turntable which swings the whole house around. One moves the boom up and down. The other two control the cables. [Illustration] At the same time, Charlie must watch what’s going on outside. A man stands on the job giving signals. Thumbs up mean “Take the boom up.” Thumbs down mean “Lower the boom.” When the signal man points up with his first finger, it means “Raise the cable.” If he wiggles the finger, it means “faster.” When Charlie is lifting a beam and has to hold it for a while in the air, he says he “takes a strain and dogs it off.” Dogging is his word for setting the brake on the cable. Things are always likely to fall around a construction job, so the men who work on the ground have steel caps in their shoes to protect their toes. They wear steel helmets on their heads, too! As the building goes up, Charlie’s crane lifts loads higher and higher. After a while he has to put a jib on the boom. This is an extension that makes it longer. When the building goes too high for his crane to reach, Charlie works another crane. It sits on top of the building’s framework and reaches down from there. [Illustration] After Charlie lifts a big steel girder into position, other men bolt it in place then fasten it tight with rivets. A man called a heater gets the rivets red-hot in a fire. Using tongs, he tosses them one at a time to the catcher who reaches for them--not with a mitt but with a kind of cup. The catcher pokes a rivet in a hole, and two other men fasten it tight. One of them, the bucker, holds the rivet in position with a bar, and the rivet man pounds the other end flat with a rivet gun. (The gun works like a jack hammer, and it makes an awful racket.)