176 



afterwards bitter and acrid taste ; dissolves in water and alcohol, 

 not in ether; froths with water, gives pi-ecipitates with acetate 

 and sub-acetate of lead. Separates, by l)oiling witli diluted acids, 

 into sugar and a white substance, insoluble in water. — Baron F. 

 von Mueller and L. Rummel.] 



Pityxylonic Aci(l=:C25 H20 Os. In the stem of Pinus 

 sylvestris, probably also in Pinus Abies and other species. Boil 

 the finely rasped wood with water, strain, evaporate the liquid 

 mixed with carbonate of baryta to a small bulk, filter, evaporate 

 again and treat the remnant with ether. Digest the exhausted 

 mass with alcohol, which dissolves the P. acid, and leaves it after 

 evaporation. — Brown-yellow, amorphous, hygroscopic mass, very 

 bitter, of acid reaction; dissolves slowly in cold, i-eadily in boiling 

 water with pale-yellow colour, readily in alkaline water. 



Pluillbagill. Acrid, crystalline ingredient of Plumbago Europsea. 

 Draw out the bark of the root with ether, evaporate the liquid, 

 boil the extract with water and purify the Plumbagin, which will 

 have subsided on cooling from the decoction, by recrystallising in 

 ether or in ether-alcohol. — Ciystallises in delicate, orange-yellow, 

 tuftily-united needles, tastes at first sweetish, ii-ritating, afterwards 

 bux'ning and acrid, fuses readily, volatilizes partly unaltered, is of 

 neutral reaction, dissolves sparingly in cold, more in hot water, 

 readily in alcohol and in ether. Sulphuric and nitric acids dissolve 

 it with yellow colour, ammonia with red colour, and acids restore 

 the yellow colour. The aqueous solution becomes likewise 

 coloured with sub-acetate of lead, iinder formation of a carmine- 

 red precipitate. 



Polleilill. The main ingredient of the pollen remains, after 

 the pollen has been treated successively with water, alcohol, 

 ether, diluted acids and alkalies. — Subtle, light, tasteless powdei-, 

 putrifies in the moist state under evolution of ammonia. Is most 

 likely not quite pure in this state, and perhaps in the main 

 cellulose. 



Polycln'oit= Crocin. 



Poly«alm= Saponin. 



[PolygOlliC acid. Prepared by Rademaker from the herb of 

 Polygonixm hydropiper, by exhausting with dilute alcohol, evapo- 

 rating to one-third, filtering and precipitating the filtrate by 

 acetate of lead. The precipitate is well-washed, decomposed by 

 sulphuret of hydrogen and the filtrate treated with ether, which 

 dissolves the P. acid, and leaves it behind on evaporation. — Green, 

 deliquescent, crystals of an acrid, bitter taste, and strongly acid 

 reaction, soluble in alcohol, ether and chloroform, less so in 

 aqueous alcohol; neutralise the bases completely, forming well- 

 defined salts.] 



