6 CEOP PLANTS FOR PAPER MAKING. 



THE OUTLOOK FOB, UTILIZATION UNDER PRESENT-DAY 



CONDITIONS. 



About half a century ago the supply of rags became so low and the 

 price as a consequence so high that paper manufacturers were forced 

 to find new materials as a basis of tlie furtlier development of their 

 industry. In this extremity esj^arto grass and certain woods, notabl}'' 

 spruce and poplar, were found to produce excellent paper fiber. 

 The enormous expansion in the use of paper since that time has now 

 brought us face to face with a dearth of suitable wood. The price 

 of spruce at the mill has risen from a few dollars a cord to $6 to $11, 

 and in some cases even to $12 a cord, according to location and cost of 

 delivery. Poplar, likewise, has risen from a comparatively low price 

 until now it is perhaps worth on an average $7.50 per cord, delivered. 

 Practically all the trees producing the highest class of materials have 

 been cut, so that the present harvest is from less desirable and more 

 scattered stands, which means reduced yields of fiber in raw mate- 

 rial and an increased cost in securing the wood. While the price of 

 wood has continually advanced as the supplies grew smaller, the 

 supply of crop by-products has gone on increasing with practically 

 no increase in price, and with but little likelihood of any considerable 

 increase in the future. In course of time this disparity will become 

 even more pronounced ; hence attempts at the utilization of waste 

 materials are now made under conditions far more favorable than 

 were similar efforts made as recently as 10 or 15 years ago. In 

 other words, the rising cost of materials is rapidly bringing us to a 

 time when the question of producing paper from crop wastes and 

 other plants may be considered from a new point of view. 



METHODS USED IN OBTAINING PAPER STOCK FROM PLANTS. 



AVith the exception of cotton, all raw vegetable fibers that enter 

 into the manufacture of paper pulp are obtained by the mechanical 

 or chemical separation of complex plant tissues. As a preliminary 

 to the discussion that folloAvs, a short description of the methods by 

 which paper fiber is secured from trees and otiier plants may not be 

 out of place. 



The simplest method, that of mechanical grinding, is applicable 

 only to certain woods, which are ground into a pulp by means of 

 grindstones over wdiich a continuous stream of water flows. The 

 pulp secured in this way is the poorest of all, as it contains numerous 

 substances which rapidly deteriorate in contact with light and air. 

 This sort of pulp, known as mechanical wood pulp, mixed with a 

 fair proportion of higher grade fiber, is the chief constituent of news 

 and other cheap printing papers. It is also used largely in the 



S^The paper upon which this page is printed icas .7)iade from rice straw and 

 spruce wood. See page 3. 

 [Cir. 82] 



