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Copaivic Aci(l:=:C4o H29 O3 + HO. In the balsam of Copaiva 

 as hard resin besides a volatile oil and a soft resin. To prepare 

 it, mix nine parts balsam with two or more parts liquor of am- 

 monia of 0'95, and let stand cold in a closed vessel whereby at 

 10° only after several weeks, at - 12° after twenty-four hours, white, 

 shining needle-like crystals will be formed. Drain and shake the 

 crystals with a little ether, which dissolves the balsam and leaves 

 the crystals little altered, press and recrystallise in absolute 

 alcohol. — Long, translucid or transparent, colourless crystals of 

 faint smell and bitter taste, of acid reaction, insoluble in water, 

 readily soluble in absolute alcohol, less so in aqueous alcohol and 

 in ether, in permanent and volatile oils, in concentrated sulphuric 

 acid with red-brown colour ; also in jjotash-ley but reprecipitated 

 by an excess of the solvent. 



Copal. Resinous exudation of several trees, viz., "Valeria 

 Indica, Hymeneea Courljaril, Trachylobium Gaertnerianum, 

 Cynometra Spruceana, Youapea phaseolocarpa, Bursera Copal, and 

 other species of these g-enera. Shows, according to its origin, 

 some physical and chemical distinctions, but is in general pale or 

 brownish-yellow, translucid or transparent, hard and brittle, 

 without taste or smell, heavier than water, fusible without 

 noticeable smell, but with a change of properties, yields in higher 

 temperatures volatile oil and water. It dissolves little in absohxte 

 alcohol, more readily when exposed to the air for a long time,^ 

 more readily still after melting or with an admixture of camphor ;. 

 swells up in ether and dissolves completely, also in caustic alkalies, 

 copiously in chloroform, slowly in benzol and castor oil, partly in 

 sulphide of carbon and in volatile oils. Five mostly acid resins 

 have been obtained from Copal through the agency of different 

 solvents. 



Copalcliill. Alkaloid of the Copalchi-bark (from Croton 

 niveus), of which is only known that it is distinctly crystalline, 

 tastes similar to quinin, dissolves in ether, is precijntated white 

 by alkalies from its solution in acids, and behaves towards 

 chlorine and ammonia like quinin (turns dark-green). 



Coriamyitill=C4o H24 O14. Bitter ingredient of the leaves 

 and fruits of Coriaria myrtifolia. Precipitate the juice of the 

 fresh or the aqueous extract of the dried plant with subacetate of 

 lead, remove the excess of lead from the filtered liquid by means of 

 sulphuret of hydrogen and evaporate to the consistence of syrup. 

 The residue yields up to ether the C. which is obtained by 

 evaporation, and purified by recrystallising in alcohol. — Forms 

 white, four to six sided klinorhombic prisms, very bitter ; loses 

 nothing of its weight at 200°, fuses at 220°, is decomposed by 

 higher temperatures; of neutral reaction; dissolves at 22° in 

 70 parts cold and a little more in boiling water ; in 50 parts cold^ 



