Showmanship in Advertising (1949)

Irs Hisrory 67 being applied. The papyrus was then soaked, pressed and pounded until a smooth, homogeneous surface was obtained. Sun-dried, it became tough and durable. Manuscripts on papyrus have survived for thousands of years. The making of parchment from the skins of sheep or calves began as early as the 2nd century, B. C., the finest parchment (from the skins or intestines of calves) being known as vellum. The use of parchment was continued for important documents and manuscripts for centuries after the introduction of paper. Arabian manufacture of paper from flax began at Samarkand in the 8th century, the Arabs learning the art from the Chinese who had retained the secret for nearly six hundred years. The first European paper was made by the Moors in Spain in the 12th century and paper was first produced in the United States in the 17th century. Early paper was manufactured from almost every kind of vegetable fibre. Much paper today, of varying quality, is made from cotton, flax, straw, hemp and other fibrous materials as well as from waste paper. The making of paper has changed but little basically—except that today most paper is manufactured by machine from the cellulose fibres of cleaned and pulped wood—although the most durable of paper utilizes cotton or linen rags. Other substances may be employed in the manufacture of paper, such as clay, titanium oxide, zinc sulphate, talc, resin, coloring—and water. The idea of making paper from wood pulp was gained in 1719 by a French scientist, Rene de Reamur, when he observed a wasp chew pieces of wood and convert them to pulp to build a nest. Wood used in paper making is first barked—the bark, which cannot be used, being removed by hydraulic pressure or by knives or friction. In the mechanical process, and especially for newsprint, wood may be ground into pulp by forcing it against revolving grind stones. Or wood may be reduced to pulp by one of several chemical processes. Wood is cut into chips asa first step in the chemical process, then conveyed to cookers. The acid cooking solution (calcium bisulphite or caustic soda, plus live steam) in these digesters separates the fibres and eliminates other elements (lignin, resin, sugar and mineral salts). Different woods require different cooking methods. Calcium sulphite is used for long-fibred pine, hemlock, spruce and other coniferous woods; caustic soda for short-fibred decidious woods, as beech, birch, poplar and cottonwood. The sulphate process uses both sodium sulphate and caustic soda. After cooking, the pulp may be bleached by a chlorine process. Then, suspended in water, the pulp goes into beaters where rubbing and cutting further fray and separate the fibres to improve felting. Paper consistency is affected by