169 



leum ether, and alcohol, little in water; fuses at 156°; does not 

 completely neutralise acids.] 



Pectin, A matter, the chemical constitution of which is not 

 known. It contains a larger amount of oxygen than the carbo- 

 hydrates, and cannot therefore be regarded as one of the series. It 

 occurs especially in fleshy fruits and roots, and is recognisable by 

 its property of coagulating like a jelly, when the juice of such 

 vegetable ])arts is mixed with alcohol. By pressing this jelly, re- 

 dissolving in hot water, precipitating with alcohol, and drying the 

 deposit of Pectin, it is obtained as an almost colourless, gummous, 

 half-transjiarent, foliated, tasteless substance, which dissolves in 

 water to a slimy and very thick liquid ; it yields with nitric acid 

 oxalic and mucic acids, A\'ith diluted sulphuric acid no sugar but 

 other kinds of metamorphoses, as likewise by boiling with watei-. 

 It contains always one or more per cent, of lime-compounds. 

 Pectin, gum, and mucilage cannot be sejiarated from each other, 

 as they are all prepared and isolated in the same manner ; as a 

 distinguishing character of Pectin from either of the two serves 

 its property of setting into a jelly, as mentioned above. 



Pelarg'OUic Acicl=Cis H17 O3 4- HO. In the volatile oil of 

 Pelargonium. Distil the herb with water, saturate the distillate 

 with baryta, distil off the neutral oil, and decompose the remaining 

 Pelargonate of baryta with sulphuric acid. The acid separates, 

 and has, after washing, to be desiccated by means of chloride of 

 calcium. — Colourless, oily liquid, smells faintly of butyric acid; 

 congeals when cold, and fuses at 10° ; boils at 260°, and distils 

 unaltered; dissolves little in water, readily in alcohol and in 

 ether. The Pelargonates of the alkalies and of the alkaline 

 earths are soluble in water. 



Pelosilli^Cse H21 NO 6. Alkaloid of the root of Cissampelos 

 Pareira. Boil with water containing sulphuric acid, saturate the 

 united decotions with carbonate of soda, collect the deposit, wash, 

 dry, re-dissolve in acid water, treat with animal charcoal, filter, 

 precipitate again with carbonate of soda, dry, draw out with 

 absolute ether, and evapoi'ate the ethereous solution. — Yellowish, 

 amor])hous mass, friable to a white powder, of a disagreeable 

 sweetish-bitter taste, of alkalme reaction ; dissolves not or little 

 in water, most readily in alcohol, slowly but abundantly in ether; 

 with ether containing water, hydrated Pelosin (with 3 eq. water : 

 a nearly white amorphous powder) is formed, which does not dis- 

 solve in ether. It fuses readily when warmed, and is decomposed 

 by more heat ; becomes brown when exposed to damp air, especially 

 in the presence of alkalies. Its salts are not crystallisable, only 

 the chloride of P. forms warty concrescences. [According to 

 Flueckiger and Hanbury, Pelosin is identical with Bebirin.] 



