CRUDE DRUGS. 44i 



Description. A white, soft tufted mass, consisting of some- 

 what flattened, twisted and spirally striate, i -celled, non-glandular 

 hairs, from 2.5 to 4.5 cm. long; inodorous and tasteless. 



Absorbent cotton is soluble in ammoniacal solution of cupric 

 oxide, yields less than i per cent, of ash, and on treating it with 

 water the solution should have a neutral reaction and not give any 

 reaction with ammonium carbonate, barium chloride, mercuric 

 chloride or silver nitrate. 



Adulterants. Various substances may be added to absorbent 

 cotton to increase the rate of absorption of water, as chlorides of 

 calcium, magnesium and zinc, glycerin and glucose; as loading 

 materials, barium and calcium salts, and clay are added to inferior 

 grades of the article. 



The hairs from immature seeds are known as " dead cotton " 

 and are distinguished by having very thin walls, a thin outer 

 layer of cutin, but lack the essential properties for technical uses. 



GUARANA. A dried paste consisting of the crushed seeds 

 of Paullinia Ctipana (Fam. Sapindacese), a climbing shrub native 

 of Brazil and Uruguay. The commercial product is obtained from 

 cultivated plants. The ripe seeds are deprived of the appendage 

 or aril, crushed, made into a doughy mass with ^yater, sometimes 

 tapioca being added to increase the adhesiveness, molded into 

 forms and dried at a gentle heat. During the drying the mass 

 undergoes a kind of curing. Considerable skill is required in 

 supervising the operation, which is performed by special work- 

 men. In addition to its use in medicine, Guarana is used in the 

 preparation of a beverage which is used like tea and cofifee by the 

 people of Brazil (p. 324). 



Description. Cylindrical sticks, 15 to 30 cm. long, 35 to 50 

 mm. in diameter ; externally blackish-brown, -surface marked by 

 depressions, but otherwise smooth ; hard, heavy and brittle, the 

 fracture being uneven ; internally light brown to reddish-brown, 

 somewhat variegated from the fragments of contused seeds ; odor 

 slight; taste astringent, bitter. 



Constituents. CaiTeine 2.5 to 5 per cent. ; tannin (catechu- 

 tannic acid) about 25 per cent. ; ash about 2 per cent. Guarana 

 also contains considerable starch, a small amount of catechin, a 

 volatile oil, an acrid, green fixed oil, and saponin. (Also see Cola.) 



