THE JOURNAIv OF PHARMACOLOGY. 227 



Several factories distinguish between several sorts thus, for example : 



1. Shoddy or thibet (from rags of best wools, long-fibered). , 



2. Flannel (from white flannel). 



3. Mungo (from fulled fabrics). 



4. Knitted wools (from tricots). 



5. Alpaca (from half-wool rags). 



6. Damask (from upholstery goods). 



7. Merino (from merino wool fabrics). 



In Brunn distinctions are made between old cloth mungo, new cloth 

 mungo, soft wool shoddy (from carded yarn materials), thibet, alpaca 

 (extract) (from unfulled), alpaca II (from fulled cloths). 



Practice and exactness are prerequisites when examining yarns and 

 fabrics (tricots, etc.) microscopically for shoddy. This is one of the most 

 interesting problems of technical microscopy, also one of the most delicate 

 as well as difficult operations. 



It cannot be seen on every fiber whether it is shoddy or not, and not one 

 feature will suffice but several collectively are required to be able to recog- 

 nize the presence of artificial wool in a fabric. 



It is not necessary to examine in order the most important items to be 

 considered for the detection of shoddy, but the following are of paramount 

 interest. 



I, Foreign Fibers. — Pure sheep's wool fabrics consist of but one kind of 

 fibers. Fabrics of a more expensive sort, which for that reason are made 

 of better wools, should reveal an even thickness of the single threads. In 

 no case may, for instance, a zackel wool hair be found next to a doubtful 

 merino fiber, so, in other words, all fibers present ought to be of such a 

 nature that they can be classed into one sort or some allied sorts. Varia- 

 tions in their thickness may furnish a clue as regards the quality and value 

 of the fabric, but will not furnish an indisputable result for the determina- 

 tion of the presence of shoddy ; for, as has been stated, the same fleece may 

 consist of two kinds of hairs, or the yarn might have been spun from dif- 

 ferent kinds of pure wools. 



According to C. Cramer,-'' the thickness of hairs on one and the same 

 sheep may vary from 12 to 85 m. 



It is remarkable that some even very good wools will show the presence 

 of stichel hairs (stiff, sharp, short hairs which chiefly grow on the ex- 

 tremities of sheep), these probably having come in at the shearing. The 

 latter as well as the presence of single grannen hairs (here called dog's 

 hairs), which are difficult to remove, have often been misleading and given 

 rise to the idea that a coarse mixture had occurred. But the presence of 

 these stichel and dog's hairs is exceptional, yet the possibility of their pres- 

 ence must be remembered, as well as the presence of a large number of 

 coarse grannen among the fine wool hairs. 



* Progranim des Zuricher Polytechnikums, 1881, p. 12. 



