1886.] 



MICROSCOPICAL JOURNAL. 



23 



some beautiful specimens of which 

 are in the National Museum, have 

 furnished a thread so fine that one 

 pound of it would measure 77,000 

 yards. 



For experimental purposes cotton 

 has been spun very much finer. The 

 finest cotton thread of which we have 

 any knowledge was mentioned on 

 page 217 of vol. ii of this Journal 

 where it is stated that a pound of cot- 

 ton* has been spun into a yarn over 

 715 miles in length. This repre- 

 sents 1,258,400 yards, and would 

 correspond to number 1500 thread. 

 Where this was done we do not 

 know, as the record we have does 

 not specify the mill. The Willi man- 

 tic Linen Company, of Connecticut, 

 has spun some thread almost as fine. 

 This company has spun cotton thread 

 as fine as number 1,100, which would 

 give 924,000 yards to the pound. 



The extreme fineness of this thread 

 may be better appreciated when it is 

 said that the finest thread in demand 

 is number 200, and few persons use 

 anything finer than 150. We have 

 some specimens of 400 three-cord 

 thread, 112,000 yards to the pound, 

 from the Willimantic Company which 

 measures about 100// or .0039 ^^^^^ 

 in diameter. This represents the di- 

 ameter of three threads twisted to- 

 gether, from which some idea of the 

 extreme fineness of the higher num- 

 bers may be formed. 



There are many plants growing in 

 difierent parts of the world which are 

 of more or less value as sources of 

 textile fibres ; some of them are only 

 useful where they grow for making 

 ropes, or nets for fishing, others have 

 already acquired more or less com- 

 mercial importance, and are used in 

 the manufacture of paper or for mix- 

 ing with more valuable fibres in spin- 

 ning. 



It becomes, then, a matter of con- 

 siderable importance to be able to 

 distinguish fibres of different kinds in 

 woven fabrics, and this is only possi- 

 ble by the aid of the microscope. 



The microscopical examination of 



fibres also leads to more than a 

 knowledge of the peculiarities of 

 fibres and the means of distinguish- 

 ing between them. In the hands of 

 experienced persons the microscope 

 throws much light upon questions of 

 practical importance to spinners of 

 yarns and to dyers. This is a branch 

 of the subject that is too technical for 

 this place. It may be said, however, 

 that the value of a fibre for spinning 

 depends upon its fineness, supj^leness, 

 length, and strength. In the case of 

 wool we have the further qualities of 

 natural curliness and imbricated sur- 

 face, which causes the fibres to cohere 

 and mat together. The ramie is ex- 

 ceedingly well adapted to spinning, 

 the fibre being very soft, averaging 

 about 1 20mm. in length. Obviously 

 it has a great advantage over cotton 

 in respect of length. The cotton 

 fibre, however, makes durable gar- 

 ments by reason of its great softness 

 and flexibility, due to the purit}- of 

 the cellulose of which it is composed. 



In this article we shall confine our- 

 selves to the examination of fibres 

 from the vegetable kingdom. 



The best authority upon the micro- 

 scopical characters of vegetable fibres 

 is M. V^tillart, whose valuable work. 

 • Etudes sur les fibres,' is the most 

 complete yet published, although it 

 only treats at length of a compara- 

 tiveh' small numberof the textile fibres 

 now more or less used. M. V^tillart 

 examines fibres in several ways, and 

 one cannot do better than follow the 

 course he has laid down. We shall 

 give the method of examination as 

 carried out in the National Museum 

 for the examination of fibres, and the 

 method of mounting specimens for 

 microscopical study, or for reference 

 and comparison. 



The fibres are first separated from 

 each other, so that single ones can 

 be readily collected and isolated. In 

 most cases a simple soaking or boil- 

 ing in water suffices to effect the 

 separation, but if not, boiling in a 

 weak solution of washing soda soon 

 removes the resinous or gummy ma- 



