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Ericolin=:C68 H56 042- Bitter glucosid of Arctostaphylos 

 Uva ursi, Calluna vulgaris, Erica herbacea, Ledum palustre, Rho- 

 dodendron ferrugineum, consequently a widely distributed con- 

 stituent of tbe Ericaceae, and to be sought for in many other co- 

 ordinal plants. Boil (preferably Ledum palustre) with water, 

 strain, precipitate with subacetate of lead, evaporate the filtered 

 liquid to one-thii'd in a retort, remove by filtering the lead com- 

 pound which will have separated ; throw down the rest of the lead 

 from the liquid with sulphuret of hydrogen, evaporate to honey- 

 consistence and extract the Ericolin by means of dehydrated 

 ether-alcohol. The residue left after the evaporation of the latter 

 is dissolved several times with ether-alcohol and evaporated \intil 

 it dissolves without any residue. — Brown-yellow powder, con- 

 glutinating at 100°; of very bitter taste, breaks up, when heated 

 with diluted sulphuric acid, into sugar and Ericinol. 



El'UCic Acicl=C44 H41 O3 -1- HO. In the fixed oils of white 

 and black mustard and of rape. Saponify the oil ^vith soda-ley, 

 decompose with hydrochloric acid, dissolve the fat acids in hot 

 alcohol, keep in a cold place, press the separated mass and recrys- 

 tallise. — White, glossy, thin crystallised needles, without smell or 

 taste, fusing at 32° to 33°; decomposed in higher temperatures; 

 of acid reaction ; dissolve most readily in alcohol and in ether. 



Eriicill, Peculiar crystalline substance of the seeds of Bras- 

 sica alba. Mix the seeds, ground to a powder, with a little water, 

 allow to rest (in order to develop the acridness), treat with ether, 

 evaporate the ethereous solution to honey-consistence and leave it 

 to stand at the open aii-. After some time, hard crystalline bodies 

 will form, which are insoluble in water and alkalies, dissolve slowly 

 in alcoLol, I'eadily in ether and oils, do not redden the salts of 

 iron oxyd and contain no sulphui*. 



ErytliriC Acirt=:C4o Hoo Ooo- Exists in the lichen Lecanora 

 tartarea, more abundantly in Roccella Montagnei. Boil the lichen 

 with water, strain, rinse the white flocks and crystals which will 

 have separated after cooling with cold water, re-dissolve in hot 

 water, filter off" from the little black or brown deposit and leave to 

 stand in a cold place. — It ciystallises in colourless, fine needles, has 

 neither taste nor smell, fuses a little above 100°, is destroyed in 

 higher temperatures, dissolves in 240 parts of boiling water, better 

 in alcohol and in ether, becomes red through ammonia under 

 access of the air, yields orsellic ether on boiling "wdth alcohol. The 

 alcoholic solution assumes a purple-red colour with chloiide of iron 

 and turns yellow without cloudiness on addition of ammonia: 

 nitrate of silver effects no alteration in the alcoholic solution; 

 ammonia, when added to the mixture, yields a white precipitate 

 that turns black on boiling, while it covers the glass with a bright 

 film of silver. 



