48 



THE AMERICAN MONTHLY 



[March, 



prominent characteristics which per- 

 mit us to distinguish fibres from each 

 other. 



To simpHfy this mode of analysis, 

 and permit the reader to thoroughly 

 understand it, we shall take into con- 

 sideration only a limited number of 

 plants the fibres of which we have 

 studied ; they are those which are to 

 be found in thread, tissues or cordage 

 which may be met with to-day in the 

 markets of Europe. 



The results obtained will be plain 

 at first sight only in proportion as the 

 specimen be crude or imperfectly 

 bleached. In both cases it will be 

 necessary to boil it in a solution of 

 carbonate of soda and to disintegrate 

 it by braying in a mortar, as we have 

 already explained. The analysis of 

 white or dyed tissues gives results 

 quite as accurate, but demands a cer- 

 tain experience in these researches, 

 and the most scrupulous care. 



The mode of procedure is the same 

 whether the specimen be composed 

 of filaments of one kind or of a mix- 

 ture of many textiles. This process 

 difiers from the metliod of chemical 

 analysis in that the latter necessitates 

 the employment of many reagents in 

 succession, each test indicating the 

 presence or absence of one or more 

 substances ; while the method which 

 we propose employs only a single re- 

 agent, complex, it is true, but the 

 same in all cases, and which, added 

 to the indications given by the micro- 

 scope, permits us to identify the fila- 

 ments enumerated, or the presence of 

 a number of them at the same time in 

 one specimen. 



We divide the filires into two 

 classes : — 



Class A embraces those which are 

 colored blue by the reagents ; 



Class B, those which take a yellow 

 color under the same conditions. 



The letter i. indicates the average 

 length of the fibres ; d, the average 

 diameter; r, the proportion of the 

 average length to the average diame- 

 ter. Each class will be divided into 

 two sections : Section I will contain 



the fibres obtained from the dicotyle- 

 donous plants ; Section II, those from 

 the monocotyledonous. 



CLASS A. 

 SECTION I. 



D it o t y I e dons . 

 This section includes Flax, Hemp, Hop- 

 fibre, the cominon Nettle, the Chinese 

 Nettle, the Paper Mulberry, the Sunn 

 Hemp, the Broom and the Cotton 

 plant. 



I. Sections blue or violet, not en- 

 closed in or surrounded by a yellow 

 border ; with yellow in the inner 

 cavity. 



a. Sections polygonal with straight 

 sides, having angles more or less acute ; 

 in the center a yellow point ; concen- 

 tric layers of growth slightly indicated. 



Fibres of a blue color, transparent, 

 regular, smooth or slightly striated ; 

 folds of a blue color somewhat de- 

 pressed by the swelling of the body 

 of the fibre ; central canal represented 

 by a narrow yellow line, granulated ; 

 with slender, sharp points. 



L. 25"™ to 30°'"' ; D. o""", 020 ; 



K. 1200 Flax. 



d. Sections oval, fiat or with re- 

 entrant angles ; partitions somewhat 

 thick ; concentric layers of growth 

 well marked, many individual ones 

 showing radiating .striie in the interior 

 layers ; central cavity often filled with 

 a yellow granular substance. 



Fibres blue or violet, irregular, of- 

 ten striated, folded, or in ribbons ; 

 central canal generally large and 

 containing yellow granular masses ; 

 slender points, rounded at the end, 

 sometimes truncated or bifurcated. 



L. 27'""' ; D. o""", 05 ; 



K. 550 . . . Common Nettle. 



c. Sections polygonal or irregular, 

 of very large size, often with re-en- 

 trant angles ; the inner opening large 

 and irregular, sometimes containing 

 masses of yellowish-brown granules ; 

 many well-marked concentric layers 

 of difierent tints ; radiate striae in the 

 interior layers of growth in many 

 sections. 



Fibres blue or violet, some of them 



