103 



Harm ill =026 H12 N2 O2. Alkaloid of the seeds of Pegannm 

 Harmala. Exhaust with cold water, contahiing sulphuric or 

 hydrochloric acid, neutralise the free acid of the extracts, and add 

 a large quantity of a concentrated soliition of chloride of sodium to 

 throw down the hydrochlorides of Harmin and harmalin. Wash 

 these with a solution of chloride of sodium, dissolve in cold water, 

 which leaves behind dyeing matter, decolourise with animal charcoal, 

 and drop into the filtrate, heated to 50° to 60°, and under stirring, 

 ammonia, until a precipitate begins to form, which rapidly 

 increases under continued stirring without the addition of more 

 ammonia and usually contains the whole of the Harmin, but no 

 harmalin. Collect the deposit obtained hereby, precipitate, if the 

 filtrate contains any more Harmin, the latter by carefully adding 

 ammonia, or remove any harmalin present from the precipitate by 

 dissolving the whole of it in an acid, and partially 2:)recipitating as 

 above. The presence or absence of harmalin for the above 

 operation may be ascertained under the microscope, for Hai-min 

 forms needle-like crystals, while harmalin crystallises in lamellary 

 form. The Harmin is afterwards puiified by recrystallising and 

 decoloiirising with charcoal.— Forms colourless, brittle prisms of 

 great lustre and light-refracting power, tasteless, liitter in solution, 

 ])ermanent at the air ; is almost insoluble in water, slowly solvible 

 in cold, more readily in boiling alcohol, slightly in ether, less so in 

 volatile and fixed oils. Forms with acids colourless, or slightly 

 yellowish, crystalline salts, the concentrated solutions of which 

 have a yellowish colour, while in the diluted state (especially in 

 alcohol) they exhibit a bluish fluorescence. The salts dissolve 

 mostly more copiously in pure than in acid water, and their 

 aqueous solutions are ])recipitated by hydrochloric and nitric acids 

 and by chloride of sodium and nitrate of soda. Caustic alkalies 

 thi'ow down the base. 



Hazelnut Oil, obtained by pressing the seeds of Corylus 

 Avellana and other species of that genus. Pale-yellow, thickish, 

 mild, inodorous, of 0-924 density, solidifies at 19°. Belongs to 

 the non-drying oils. 



Hederic Acid^Cso Hoe Os- In the seeds of Hedera Helix. 

 Free the seeds from fat by means of ether, boil the remnant with 

 several changes of alcohol, distil off one quarter of the alcohol 

 from the tinctures and allow the impure acid to separate. It is 

 difticult to procure it in the pure state, and has been only once 

 obtained pure by keeping the ether-alcoholic solution at rest for 

 some time. — Fine, white, soft crystalline needles and lamellae, 

 inodorous, of very acrid taste and slightly acid reaction, not fusible 

 by heat, insoluble in water and ether, soluble in alcohol, in con- 

 centrated sulphuric acid with beautiful purple-colour. Yields 

 amorphous, jelly-like salts with alkalies and alkaline earths, 



