To-day the United States leads the world in the production of paper. According to the census of 1909, we produced 4,216,708 tons, valued at $232,741,049, an amount which exceeds in tonnage the combined production of England, Germany, France, Austria and Italy. Well may we be proud of this great industry, which after all is largely the reflection of a nation’s intelligence and culture, and commercial activity. CHAPTER TWO RAW MATERIALS Paper has been defined as “an aqueous deposit of cellulose,” and while this is incomplete as a catalogue of the materials composing a sheet of modern paper, it is an excellent epitome of the foundation of paper-making. Minute cellulose fibers, derivatives of various raw materials, are deposited upon a wire cloth by the passage of a volume of water in which they have been suspended. The pulpy film thus formed becomes a sheet of paper, after the expulsion and evaporation of the water which served as a medium for their deposit. The minute fibers composing this hypothetical sheet of paper may have been isolated from one of several sources of raw materials in present commercial use, or the sheet may be composed of a mixture of different fibers, all more or less pure cellulose, in accordance with the preliminary treatment each has undergone. The principal sources from which American paper fibers are derived are cotton and linen rags, hemp, jute, wood, straw; and waste papers. Previous to the year 1840, the sources were limited to rags. These are almost wholly composed of pure cellulose fibers, which give up their non-cellulose concomitants with slight resistance. The more severe chemical treatments necessary for the isolation of cellulose fibers, from wood, for example, half of which is non-cellulose in structure, were unknown to early paper-makers, and only became possible after the discovery of bleaching-powder by Tennant, and the manufacture of soda by Le Blanc. Although experiments in search of suitable substitutes for rags began to be made in the eighteenth century, it was Keller’s invention of ground wood in 1840, Routledge’s work on esparto grass and wood with a soda process in 1854, and our own fellow countryman Tilghmann’s patent of the sulphite process in 1866, from which we may date the beginnings of the now extensive use of materials other than cotton and linen wastes. The accompanying table, taken from the United States Statistics of Manufacture for 1909, gives an illuminating indication of the rapid growth of our paper industry, and also shows the remarkable increase in the use of wood celluloses. Note.--Statistics are taken from U.S. Reports for 1909. Subsequent reports are obtainable from the Director of the Census, Washington, D.C.