Engineering Wonders of the World
Volume III

REMARKABLE MACHINERY. 263 AN “IRONCLAD” MAGNET LIFTING A G-TON SKULL-CRACKER BALL. A SKULL-CRACKER BALL SMASHING SCRAP AT THE BALDWIN LOCOMOTIVE WORKS. {Photo, Electric Controller and Supply Company, Ohio.) striking application of the magnet is seen in the lifting of the large balls, sometimes called skull-crackers, which break up large pieces of scrap for remelting. A magnet forms an ideal means of raising these balls, for in nine cases out of ten a skull-cracker fitted with a ring for ordinary hook-tackle will fall with the ring downwards, and a lot of work and time must be expended in getting at the ring to replace the hook. Also, when a magnet is used, the ball is released merely by switching off the electric current. We have now outlined roughly the progress of iron from the ore to the pig stage. The next thing to consider is the transformation of pig-iron into steel. There are two prin- cipal methods of converting pig-iron into steel—the Bessemer process, and the open hearth process. The Bessemer process is the oldest, and was patented by Sir Henry Bes- semer in 1855—from which year the com- mercial manufacture of steel dates. The process consists in blowing air through