CORTEX ANGOSTURA. 107 



The bark has a short, resinous fracture, and displays on its transverse 

 edge sharply defined white points, due to deposits of oxalate of calcium. 

 It has a bitter taste and a nauseous musty odour. 



Microscopic Structure — The most striking peculiarity is the great 

 number of oil-cells scattered through the tissue of the bark. They 

 are not much larger than the neighbouring parenchymatous cells, and 

 are loaded with yellowish essential oil or small granules of resin. 

 Numerous other cells contain bundles of needle-shaped crystals of 

 o.xalate of calcium or small starch granules. The liber exhibits bundles 

 of yellow fibres, to which the foliaceous fracture of the inner bark is 

 (.lue. The structure of the bark under notice has been very minutely 

 described and figured by Oberlin and Schlagdenhauffen.^ 



5osition — Angostura bark owes its peculiar odour 



m 



H 



of f per cent. It is probably a mixture of a hydrocarbon (C"'H"') 

 ^^■ith an oxygenated oil. Its boiling point is 266° C. Oberlin and 

 SchlagdenhaufFen obtained OlO per cent, of the oil, and found it to 

 be slightly dextrogyre ; it assumes a fine red colour when shaken 

 with aqueous ferric chloride, and turns yellow with concentrated 

 sulphuric acid. 



. The bitter taste of the bark is attributed to a substance pointed out 

 in 1833 by Saladin and named Cusparin. It is said to be crystalline, 

 neutral, melting at 45° C, soluble in alcohol, sparingly in water, pre- 

 cipitable by tannic acid. The bark is stated to yield it to the extent 

 01 1'3 per cent. Herzog endeavoured to prepare it but without success, 

 nor have Oberlin and SchlagdenhaufFen met with it. The latter 

 fnm"?''^' °^ ^^6 otl^er hand, isolated an alkaloid Angosturhe 

 y ^ NO". It is in thin prisms, melting at 85° and yielding a crystal- 

 n^ed chlorhydrate or sulphate. Angosturine turns red when touched 

 ^^ith concentrated sulphuric acid, or green if nitric acid or iodic acid, 

 or other oxydizing substances, have been previously mixed with the 

 ^yiphunc acid. The alcoholic solution of the alkaloid is of decidedly 

 Kahne reaction. A cold aqueous infusion of angostura bark yields 

 of tl. ^"^^^^ red-brown precipitate with ferric chloride. Thin slices 

 f_ . "^^^k are not coloured by solution of ferrous sulphate, so that 

 ^annm appears to be absent. 



aj.,i^^^^"~^ngostura bark is a valuable tonic in dyspepsia, dysentery 

 Chrome diarrhoea, but is falling into disuse. 



Adulteration— About the year 1804, a quantity of a bark which 



o^ed to be that of Strychnos Nux Vomica reached Europe from 



alar^' ^^^} ^^'^^ mistaken for Cusparia. The error occasioned great 



tticT ^°"^® accidents, and the use of angostura was in some coun- 



^ ^s even nrohibiff.,! i^i.^ ,„,.,,v.c. ^f riic5finrfiii«hin<T tlie two barks 



, i 



(which 



prohibited. The means of distinguishing the two barks 



thp iv ^^"® ^^^ likely to he again confounded) are amply contained in 



(l877)'o.2fi ^^^' Pftann. et dr. Clumk, 28 is also figured by Berg, Anutomhcliu 



' P^^t*^« I-. 11-, III. The bark Atla.s, Tab. 37. 



2 Archivd, PJiann. xcii. (ISoS) 14G. 



