220 



easily transformed into laevulose (fruit-sugar), if its concentrated 

 solution is kept for a sliort time at 110°. Treated with nitric acid, 

 it yields oxalic acid. Deflects in solution polarised light to the 

 left. — H. Mueller.] 



Tlllucuuill=C2o Hi4 Og. Bitter ingredient of the bark of 

 Carapa guianensis. Boil the bark with water, evaporate the 

 decoctions to a thick syrup consistence, treat repeatedly with 

 alcohol of 33° Baume, warm the whole of the alcoholic solutions, 

 add milk of lime, which precipitates almost completely the 

 colouring matters, let subside, filter, add water to the filtrate, 

 distil the alcohol, concentrate the residue to honey-consistence, 

 treat with strong alcohol, eva})orate the solution to a syrup con- 

 sistence, shake the latter with chloroform and allow the chloroform 

 solution to evaporate.— Pale-yellow, amorphous substance, of very 

 bitter taste and of acidulous reaction, dissolves not in ether, 

 i-eadily in alcohol, chloroform, in 150 parts cold, and a little more 

 in hot water. "With concentrated sulphuiic acid it becomes at 

 first brown, then slowly blue; by adding immediately after the 

 acid a few drops of water a splendid blue colouration is instantly 

 produced which lasts more than twenty-four hours. A similar 

 blue tinge is obtained with hydrochloric and phosphoric acids, 

 also with warm citric, tartaric and oxalic, not with acetic or nitric 

 acids. 



'rurpeutilie. This name was originally applied to the resinous 

 exudation of the terebinth-tree (Pistacia Terebinthus), and which 

 is obtained either spontaneously or by incisions made in the stem ; 

 but afterwards all the similar exudations of coniferous trees in 

 general have been termed likewise. The Turpentines are, as a 

 rule, yellowish- white, very viscid, transparent or translucid masses 

 of honey-consistence and of acid reaction, of a peculiar, strong, 

 mostly unpleasant odour, and generally of a burning, aromatic, bitter, 

 disagreeable taste; consist chiefly of resin and volatile oil. They 

 dissolve in alcohol more or less readily, in ether, in oils, also in 

 potash-ley, the latter solution being precipitable by excess of 

 potash. According to their origin they have diflerent names. 



Turpetliin = Ces Hse O32. (Isomeric with jalapin, but not 

 identical with it.) Resinous glucosid of the root of Ipomaea 

 Turpethum. Shake with ether (which dissolves about 5%) the 

 ci'ude resin obtained by alcohol, &c. dissolve the remnant in alcohol, 

 precipitate with ether and dry.— It is not decolourised by animal 

 charcoal, is brown-yellow; inodorous, has at first no perceptible, 

 afterwards an acrid and bitter taste, fuses at 183°, dissolves 

 readily in alcohol, not in ether, separates on boiling with diluted 

 acids into sugar and Turpetholic acidrrCs^ H32 Og, a white mass 

 consisting of mici'oscopic needles and tufts, soluble in alcohol, less 

 so in ether. 



