JULY— SEPT. 1857.] 



Wood Oil 



283 



On Wood Oil 



The Balsam obtained from various trees of [the order Dipte- 

 bocarpece. 



The value and importance of this article of Indian produce in- 

 vests all information existing on the subject with much local in- 

 terest. 



Up to a recent period it appears to have been little known in the 

 Home market at least as far as regards its medicinal properties. 



In 1854 Mr. Charles Lowe, Assistant in the Royal Institution, 

 Manchester brought it to the notice of the Pharmaceutical Society, 

 under the description of " A new variety of Balsam of Copaiba" in 

 the following terms : 



" An organic fluid was lately placed in my hands by Mr. Grace Calvert 

 for examination, which he had received from an oil merchant of this city, 

 who stated that all he knew of the substance was, that it was obtained by 

 the incision of a certain tree growing on the coast of India. From the 

 characters it presents I have ascertained it to be a balsam of copaiba, but 

 as it differs in some of its properties from other balsams that I have ex- 

 amined, I forward you the following notice, in hopes that it may prove 

 interesting to some of your numerous readers. 



In appearance this balsam of copaiba is dark coloured and turbid. Its 

 turbidity is due to a greenish resinous matter, held in suspension, which 

 is, however, easily separable, either by filtration or deposition, leaving a 

 brown transparent liquid of sp. gr. 0.970. When the latter fluid is sub- 

 mitted to a careful distillation it yields : — 



Essential oil 65 per cent. 



Resin 34 „ 



Acetic acid and water 1 „ 



100 



I find that the essential oil in its various reactions with potassium, 

 iodine, nitric acid, &c, and moreover in taste, exactly corresponds with 

 those presented by pure essence of copaiba. The resin left by distillation 

 of the balsam, either with or without water, is, if deprived of the whole of 

 the essential oil, extremely hard. Its entire solubility in coal naphtha 

 proves the absence of any of the soft resin which exists in most of the 



