The Government of the United States tests paper in several ways before buying it. First, a single sheet is weighed; then a ream is put on the scales to see if it weighs four hundred and eighty times as much. This shows whether the paper runs evenly in weight. Many sheets are folded together and measured to see if the thickness is regular. To test its strength, a sheet is clamped over a hole one square inch in area, and liquid is pressed against it from below to see how much it will stand before bursting. Strips of the paper are pulled in a machine to test its breaking strength. A sheet is folded over and over again to see whether holes will appear at the corners of the folds. It is examined under the microscope to see of what kind of fibers it is made and how much loading has been used in its manufacture. To test blotting paper, strips are also put into water to see how high the water will rise on them.
Besides writing and wrapping papers and the various kinds of board, there are many sorts which are used for special purposes. India paper, for instance, is light, smooth, and strong, so opaque that printing will not show through it, and so lasting that if it is crumpled, it can be ironed out and be as good as new. This is used for books that are expected to have hard wear but must be of light weight. There are tissue papers, crêpe papers for napkins,
and tarred paper to make roofs and even boats water-tight. If tar is brushed on, it may make bubbles which will break afterwards and let water in; but if tar is made a part of the paper itself, it lasts. Paper can easily be waxed or paraffined, and will then keep out air and moisture for some time. Better still, it can be treated with oil and will then make a raincoat that will stand a year's wear, or even, if put on a bamboo frame, make a very good house, as the Japanese found out long ago. Paper coated with powdered gum and tin is used for packing tea and coffee. Transfer or carbon papers so much used in making several copies of an article on the typewriter are made by coating paper with starch, flour, gum, and coloring matter. Paper can be used for shoes and hats, ties, collars, and even for "rubbers." It has been successfully used for sails for light vessels, and is excellent made into light garments for hospital use because it is so cheap that it can be burned after wearing. Wood pulp can be run through fine tubes into water and made so pliable that it can be twisted into cord or spun and woven into "silk." Not only water but also fire can be kept out by paper if it is treated with the proper substances. An object can be covered with a paste of wood pulp, silica, and hemp; and when this is dry, a coat of water-glass will afford considerable protection. There has been some degree of success in making transparent paper films for moving pictures; and if these are coated with water-glass, they will not burn. Paper can be so treated that
it will either conduct electricity or become a nonconductor, as may be desired. In Germany, a "sandwich paper" has been made by pressing together four layers—felt, pulp, cotton, pulp—which is cheap and strong and useful for many purposes.
When we come to papier maché, there is no end to the kinds of articles that are made of it. The papier maché, or paper pulped, is made by kneading old newspapers or wrapping papers with warm water into a pulp. Clay and coloring are added and something of the nature of glue; and it is then put into a mould. Sometimes to make it stronger for large mouldings, bits of canvas or even wire are also used. The best papier maché is made of pure wood cellulose. The beautiful boxes and trays covered with lacquer which the Japanese and Chinese make are formed of this; but it has many much humbler uses than these. Paper screws are employed in ornamental wood work, and if a hole is begun for such a screw, it will twist its way into soft wood as well as steel would do. Barrels of paper reinforced with wire are common. Gear wheels and belt pulleys are made of papier maché, and even the wheels of railroad coaches; at least the body of the wheels is made of it, although the tire, hub, and axle are of cast-steel. Circular saws of pulp are in use which cut thin slices of veneer so smoothly that they can be used without planing. Papier maché is used for water pipes, the bodies of carriages, hencoops, and garages. Indeed, it is quite possible
to build a house, shingle it, decorate it with elaborate mouldings and cornices, finish it with panels, wainscoting, imitation tiling, and furnish it with light, comfortable furniture covered with imitation leather, silk, or cloth, and spread on its floors soft, thick carpets or rugs woven in beautiful designs—and all made of wood pulp. Even the window panes could be made of pulp; and if they were not perfectly transparent, they would at least let in a soft, agreeable light, and they would not break. Pails, washtubs, bathtubs, and even dishes of paper can be easily found. There are not only the paper cups provided on railroad trains and the cheap picnic plates and saucers, but some that are really pretty. Ice cream is sometimes served in paper dishes and eaten with paper spoons. Milk bottles are successfully made of paper, with a long strip of some transparent material running up and down the side to show how much—or how little—cream is within. Napkins and tablecloths made of paper thread woven into "cloth" are cheaper than linen and can be washed as easily. Paper towels and dishcloths are already common; but when paper shall fully come to its own, it is quite possible that there will be little washing of dishes. They can be as pretty as any one could wish, but so cheap that after each meal they can be dropped into the fire. Indeed, there are few things in a house, except a stove, that cannot be made of some form of paper,—and perhaps that too will be some day.
V
HOW BOOKS ARE MADE
The first step in making ready to print a manuscript is to find out how many words there are in it, what kind of type to use, how much "leading" or space between the lines there shall be, and what shall be the size of the page. In deciding these questions, considerable thinking has to be done. If the manuscript is a short story by a popular author, it may be printed with wide margins and wide leading in order to make a book of fair size. If it is a lengthy manuscript which will be likely to sell at a moderate but not a high price, it is best to use only as much leading as is necessary to make the line stand out clearly, and to print with a margin not so wide as to increase the expense of the book. The printer prints a sample of the page decided upon, any desired changes are made, and then the making of the book begins.