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THE JOURNAL OF PHARMACOIvOGY. 



The following resume considers only the more important fibers that 

 enter into the composition of paper. 



I. Lineal Fibers. — It would be erroneous to expect to find linen fibers of 

 the same appearance in paper as in the vegetable tissue. As a rule linen 

 paper is made from rags and only exceptionally from tow. In old linen 

 rags the fibers appear torn, mangled and destroyed in many places. This 

 is, of course, still more the case in paper, especially in the finer varieties. 



Characteristic of linen fibers are the knotty swellings which occur at the 

 joints. Longitudinal splits and cracks are so numerous that the lumen 

 can hardly be recognized, and the ends of the fiber are often dissected into 

 fine fibrils. 



Fig. 1. Straw Paper. — Par., Parenchyma of Center ; Epi., Irregular Epidermal Cells ; St., Stone Cell ; 

 Tr., Trichome ; S. V., P. V., Spiral and Pitted Vessels ; Fib., Bast Fibers ; X loo diam. 



2. Hemp Fibers. — In many papers these occur in a well-preserved con- 

 dition. Hemp-tow is used in papers which must combine great tenacity 

 and lasting qualities with comparative thinness, as in bank-notes, etc. 

 Papers made of old hemp-rags exhibit the same disintegrated fibers as is 

 the case in linen papers. But the hemp fibers being somewhat more 

 brittle, their torn ends have shorter fibrils than those seen in linen fibers. 

 However, there are some fibers present always which are not destroyed 

 and which render it possible to determine with certainty the presence of 

 hemp fibers even in paper. 



3. Cotton. — Cotton is always readily recognized by the well-preserved 

 wall and the ever-present cuticle of its fiber. The cuticle is, however, not 

 everywhere present and frequently is torn in many places. But the pieces 



