232 LEGUMINOS^. 



the balsam with a dilute solution of carbonate of ammonium, and pre- 

 cipitating by h}'drochloric acid. The precipitate dissolved in dilute 

 alcohol yields the acid in small crystals, but to the amount of only 

 about one per cent. 



These resin-acids have a bitterish taste and an acid reaction ; their 

 salts of lead and silver are crystalline but insoluble ; metacopaivate of 

 sodium may be crystallized from its watery solution. 



Commerce — The balsam is imported in barrels direct from Para and 

 Maranham, sometimes from Rio de Janeiro, and less often from Demerara, 

 Angostura, Trinidad, Maracaibo, Savanilla, and Cartagena. It often 

 reaches England by way of Havre and New York. In 1875 there were 

 exported 10,150 kilogrammes from Savanilla, 99,800 lb. from Ciudad 

 Bolivar (Angostura), and 65,243 kilos, from Para. 



Uses — Copaiba is employed in medicine on account of its stimulant 

 action on the mucous membranes, more especially those of the urino- 

 genital organs. 



Adulteration — Copaiba is not unfrequently fraudulently tampered 

 with before it reaches the pharmaceutist; and owing to its naturally 

 variable composition, arising in part from its diverse botanical origin, its 

 purity is not always easily ascertained. 



The oleo-resin usually dissolves in a small proportion of absolute 

 alcohol : should it refuse to do so, the presence of some fatty oil other 

 than castor oil may be surmised. To detect an admixture of this latter, 

 one part of the balsam should be heated with four of spirit of wine 

 (sp. gr. 0"838). On cooling, the mixture separates into two portions, the 

 upper of which will contain any castor oil present, dissolved in alcohol 

 and the essential oil. On evaporation of this upper layer, castor oil 

 may be recognized by its odour ; but still more positively by heating it 

 with caustic soda and lime, when oenanthol will be formed, the presence 

 of which may be ascertained by its peculiar smell. By the latter test 

 an admixture of even one per cent, of castor oil can be proved. 



The presence of fatty oil in any considerable quantity is likewise 

 made evident by the greasiness of the residue, when the balsam is 

 deprived of its essential oil by prolonged boiling witli water. 



The admixture of some volatile oil with copaiba can mostly be 

 detected by the odour, especially when the balsam is dropped on a piece 

 of warmed metal. Spirit of wine ma}'- also be advantageously tried 

 for the same purpose. It dissolves but very sparingly the volatile oil 

 of copaiba : the resins of the latter are also not abundantly soluble 

 in it. Hence, if shaken with the balsam, it would remove at once 

 the larger portion of any essential oil that might have been added. 

 For the recognition of Wood Oil if mixed with copaiba, see page 233, 

 note 1. 



Substitutes — Under this head two drugs deserve mention, namely 

 Ghirjun Balsam or Wood Oil, described at p. 88, and 



Oleo-resin of HardivicMa plnnata Roxb. — The tree, which is of 

 a large size, belongs to the order Leguminosm and is nearly related to 

 Copaifera. According to Beddome,^ it is very common in the dense 

 moist forests of the South Travancore Ghats, and has also been found in 



' Flora Syhatica for Southern India, Madras, part 24 (1872), 255. 



