Jimmy McGrath, age 10, of Peoria, Ill., for his question:
How is paper made?
Chances are, this page of paper was once part of a tall tree growing in some northern forest. The tree may have been a lofty hemlock, a fresh scented pine or a, feathery fir. Or it may have been a thick spruce, a Christmas tree 180 feet tall. One day a woodsman marked it for execution and the great tree was soon on the way to the paper mill.
A paper mill is always near a stream, for plenty of running water is needed to turn wood into paper. Here the great trees are trimmed and cut into logs. A tunnel shaped machine strips off the bark and the logs are gent to a chipper machine which flakes them into chips of an inch or less. The woody chips are hoisted up a conveyer belt to the mouth of a huge tank called a digester. The chips are dumped inside where they are mixed with liquid chemicals and cooked with steam.
The paper is made from the tough fibers of cellulose in the wood. The digesting process separates this useful cellulose from resins, cements called lignins and other waste materials in the wood. The mixture becomes a soupy pulp which goes on its way to be washed and washed and washed. Only the cellulose fibers remain in the soupy pulp.
As a rule, the pulp now goes through a tank of bleaching chemicals and on to a machine called a beater. This is an oval tank with a drum which keeps the pulp swirling. Sharp metal bars fray the fine fibers of cellulose so that they will cling and mat together to form sheets of paper. Gelatins starch and sizing materials are added in the beater, these substances will give body to the paper, make it soft or tough and it a smooth or rough surface, pulp mixture now goes to a machine called a Jordan where whirling cut the cellulose fibers into proper lengths.
The mixture is now called stuff and it is stored in a. tank called the stuff chest until the paper mill is ready to make it into finished paper. The last stage is done by a long series of rollers which press and dry the wet pulp into huge rolls of paper. The paper finally comes from the end of the last of the rollers and turning wheels all wound in a huge roll.
The roll of paper may be newsprint, made for printing newspapers. But the mill can make maybe 7,000 other kinds of paper. It can make note paper, tissue, paper for making books, magazines and even dollar bills. Each type of paper is made from its own special recipe. Recipes call for different chemicals in the digester. The cooking time will vary from two to 35 hours. The bleaching chemicals may vary. The chemicals added in the beater are very important, for they make the paper firm or soft, rough or smooth.