PAPER 



148 > 



PAPER 



ycare elapsed before the 1'iiit. -.1 States finally 



reach, "ii at tin- head of the 



world's pal* : industry. 



Manufacture. In tin- 1'nind Mate- and 

 Canada wood fiber is more plentiful than all 

 other vegetable fibers. The chief raw materials 

 from which paper is made arc spruce, hemlock. 

 poplar ami pine woo.: - -raw and old pa- 



:t 1 1 uvr- fourths of the entire output i> 

 . snufaetuivd from wood pulp. Tin- value 

 of raff paper is a little higher than that of paper 

 made from wood, but it amounts only to about 

 five per cent of the grass tonnage. Cotton and 

 linen rags were the first material of which pa- 

 .is made, the process then being almost 

 exclusively a handcraft. The rags were cleaned, 

 soaked, redueed to a pulp by beating and grind- 

 ing, and floated on water that was kept in mo- 

 tion to distribute the fibers evenly. 



When th. natural structure of a fibrous sub- 

 i- broken down, the filaments mat easily. 

 .rface of the water is thus coated with 

 a thin film or tissue of cellulose, which may be 

 described ftfi the ^keleton of plants. In the 

 earlier process this film was dipped from the 

 .n shallow boxes, fitted with a wire mesh 

 bottom, through which the water was allowed 

 to drain. Such boxes were called deckles. The 

 of forming paper were turned out on 

 i woolen felt. Layers of paper and felt 

 were placed one above another, and the whole 

 iced in a press where the remaining water 

 was squeezed out. The sheets were then hung 

 up to dry, finished by sizing with glue or gela- 

 tin and rendered smooth by pressure. Machin- 

 ery has now been substituted for hand labor in 

 the manufacture of paper. ir* 



Whatever the fiber used, the process de- 

 scribed above is essentially that used in mak- 

 ing paper. When wood i- substituted for rags, 

 the first steps of the process consist in cutting 

 logs to lengths of from twenty-four to thirty 

 inches. In the commonest process the wood is 

 then forced by water pressure against a revolv- 

 ing grindstone in such a way that the fibers 

 n from it obliquely. The pulp is strained 

 and passed on to the beating engine, where it 

 is further macerated with revolving knives. At 

 ige color and ,-i/ing are added, in addi- 

 tion to a certain quantity of chemical, or ".-u!- 

 : pem nt age of clay to act as 

 filling matter and give a smoother surface. The 

 sulphite pulp is produced by treating the wood 

 with a solution of sulphurous acid. A process 

 of cooking in vats then reduces the pulp to an 

 approximately pure cellulose fiber. If the wood 



is not treated with acids, the resulting paper i- 

 >f inferior grade, lu the Mi-called soda pTOOeOB, 

 caustic -oda is substituted for bisulphite in the 

 cooking vats. Paper so made is dark in color 

 and 1. durable than that made with sulphite. 



The pulp, once refined, bleached and colored, 

 is ready for the paper-making machine. At tin- 

 nine the Foimlrimer machine, a deli- 

 cately adjusted and most Complicated piece of 

 mechanism, i- almoM exclusively in US 

 con-i-ts of three essential parts: the "wet" part . 

 the "drying" part, and the finishing rolls, usu- 

 ally known as the calender rolls. The wet 

 stock is allowed to flow through a wide aper- 

 ture upon an endless wire screen, which moves 

 forward continuously. The speed at which it 

 moves determines the thickness of the resulting 

 paper. The width of the paper is determined 

 by the distance between the "deckles," or rub- 



r bands, placed at either edge of the screen, 

 y the time the film of pulp has passed the 

 length of the screen, it has lost enough water 

 and is felted, or twined together, sufficiently to 

 be transferred from the wire, over movable belts 

 of fell, to the pressing machine, which consists 

 of heavy rollers adjusted in pairs. Having 

 pa ed through the pressing machine, the thin 

 tissue of paper is conveyed on endless belts 

 through a number of iron cylinders, arranged 

 in horizontal tiers and heated by steam. The-e 

 are the "dryers." The final process of polish- 

 ing and smoothing is accomplished by running 

 the paper between the calender rolls. It is 

 delivered to city newspapers in massive ie< U 

 weighing about 500 pounds each. 



Classification. Paper is used for three pur- 

 poses, namely, writing, printing and miscel- 

 laneous industrial use. Under the latter head, 

 its chief uses are for wrapping, making paper 

 boxes, etc. Linen paper is favored for writing 

 and for documents which have to be preserved 

 for long periods of time. So-called linen papers 

 contain, for the most part, only a small pro- 

 portion of linen, the chief element being really 

 wood pulp. Most newspapers, magazines and 

 books are manufactured entirely of vood-pulp 

 paper, the quality being usually slightly better 

 in the case of bound volumes. Manila paper 

 is made from jute, hemp and other stout fibers, 

 and there is on the market a so-called manila 

 manufactured from wood. The variety known 

 as "boards" is used largely in bookbinding. 

 Straw paper is used for wrapping and other 

 rough purposes. The so-called watermark, by 

 which most superior grades of paper are dis- 

 tinguished, is impressed on the web while it i- 



