228 THE JOURNAL OF PHARMACOLOGY. 



Vegetable fibers may also be found in pure wools, up to one-half percent. 

 It is possible to detect even a trace of vegetable fibers by boiling the whole 

 fabric in a clean test-tube with a slightly concentrated solution of clear 

 sodium hydrate, until the wool has been dissolved ; filter the fluid through 

 a fine wire gauze and examine the residue. By this process the residue 

 will consist of plant fibers and have changed so little that it will be easy 

 to recognize cotton, jute, flax, etc. 



Sheep's wool often contains an enormous amount of so-called burs. By 

 these are meant the spiny and prickly fruits of the Xanthhun and Medicago 

 species, as well as^ the small fruits of Galium Aparine, Bidens, etc. The 

 South American wools especially are often bur wools and are loaded with 

 the fruits of the various Medicago species. These can only be removed 

 with great difficulty, in fact not entirely, and are therefore apt to be present 

 in the fabric. 



C. Cramer proved that in cloths, parts (for instance, vessels, bast fibers, 

 spines) of these Medicago seines are to be found. In the fabrication of the 

 wools the burs have been partially destroyed (partly mechanically or partly 

 by carbonization), and the resistant nerves (vascular bundles) get into the 

 yarns. The destruction of the burs may have started on the animal itself, 

 provided the wool has not been shorn too soon. This will explain the fre- 

 quent occurrence of short fibers, vascular bundles, and the like in fabrics. 



It is hardly necessary to state that now and then other vegetable tissues 

 and plant parts are found in wools and fabrics; for instance, wood, moss, 

 cotton, etc. 



It is important to remember that the vegetable fibers of artificial wools 

 as a rule have been removed by carbonization. But the absence of cotton, 

 flax, etc., does not serve as a criterion of shoddy. 



But if a certain fabric, cotton (always colored) or cosmos fibers are 

 found to the extent of several per cent., this would positively indicate 

 that shoddy (artificial wool) was present, for it would not be likely that 

 pure sheep's wool would be adulterated directly with cotton fibers. This 

 can only occur by means of artificial wool. But it is to be taken into con- 

 sideration that more than traces of dyed cotton must be present. Undyed 

 cotton if not present in noticeable quantities need not be regarded with 

 suspicion. 



2. The length of the fiber is only in individual cases of assistance in de- 

 termining the presence of shoddy. Even the best shoddy is shorter than 

 natural sheep's wool. But sheep's wool is only found approaching its real 

 length in good card yarns as well as in unshorn materials and tricots. It is 

 only possible to determine this (the length) with some accuracy in the case 

 of card yarns by carefully separating and then untwisting the netted yarn- 

 threads. It is more difficult, even impossible, to do this if the texture is 

 coarse. Also difficult in the case of tricots. Much teasing of fibers oc- 



