226 THE JOURNAL OF PHARMACOLOGY. 



of threads will be 50 per cent. Their relative weights on the other hand 

 will be i9 : 5 ^ 50 : 2 X 50 : : I : 2 33.3 per cent, cotton and 66.6 per cent, 

 sheep's wool. 



Finally it is to be remarked that the same method of examination may 

 be employed with other fibers. It is easy to deduct data from state- 

 ments made in their respective places, concerning the shapes of the 

 cross sections of the fibers. But in no instance is the question so im- 

 portant as in case of cotton and sheep's wool and for this reason it has 

 been discussed in detail. 



Microscopical Examination of Shoddy (Artificial Wool, Al- 

 paca, MuNGO, Extract.) 



The reproduction of woolen fibers, that can be spun, from woolen rags, 

 an industry which had its origin in England about 1845, has become so 

 universal on the Continent and in America that about 33 per cent, of fab- 

 ricated wool is artificial wool. In fact, in all countries of Europe there are 

 shoddy factories whose yearly output amounts to about 150-200 million ki- 

 lograms. As sheep's wool is four to six times more expensive than rag 

 wool, it becomes evident that not only all the cheaper woolen fabrics con- 

 tain shoddy, but that some fabrics whose prices would admit the presence 

 of real wool only, are more or less adulterated with it. 



Grothe * found, after examining numerous samples of carded yarns, that 

 but 15 per cent, of these were free from muugo. Hundreds of English 

 and Briiner fabrics examined by v. Hohnel showed the exceedingly fre- 

 quent occurrence of shoddy in fabrics. 



As in the case of sheep's wool, there are many grades of artificial wools, 

 and it is necessary for several reasons to mention them. 



This artificial wool is classed as shoddy, alpaca and mungo. 



Shoddy is obtained from pure unfuUed (unmilled) sheep's woolen fab- 

 rics ; also from pure (sheep's) woolen worked and knitted materials (tri- 

 cots), and finally from materials that have not been shorn (for instance 

 llama). The fiber is usually pure and over 2 cm. long. 



Alpaca, sometimes called extract, is obtained from the same fabrics 

 (rags) if they also contain vegetable fibers. The latter can only be re- 

 moved by a carbonizing process invented by Kober. By this process the 

 rags are treated with sulfuric acid 4 per cent., then dried in special drying 

 ovens at 60° to 80° C. ; the vegetable fibers are then destroyed and can be 

 easily removed by beating the material, whereas the firmness of the sheep's 

 wool is hardly affected. The excess of acid must be removed by soda and 

 thorough washing. Usually over 2 cm. in length. 



Miingo (origin : it must go; it mun go) is obtained from pure or impure 

 cloths (fulled). The fiber is short, about 5-20 mm. long. 



*Zeitschrift der Wollinteressenten Deutschlands, 1875. 



