Medico-Bolaniccil Society. 221 



New Essential Oil of Laurus, (written by Dr. Hancock of De- 

 merara, and communicated to the Society by Lieut. Friend, 

 R.N. F.R.S.) were read.— 



" The knowledge of this oil has hitherto been almost exclu- 

 sively confined to the natives of Spanish Guiana, This sub- 

 stance, which has been very injudiciously termed Azcijte de 

 Sassafras, (an appellation which tends to confound it with the 

 essential oil yielded by the Laurus Sassafras of the northern 

 continent of America,) affords, so far as my knowledge ex- 

 tends, an extraordinary and solitary instance of the produc- 

 tion of a perfectly volatile liquid without the aid of art. Sub- 

 stituting Ibr the appellation to which I have objected the pro- 

 visional name ' Native Oil of Laurel,' I shall describe the me- 

 thod of procuring it, and enumerate its principal chemical and 

 medicinal properties, so far as they have been investigated and 

 examined. The native oil is yielded by a tree of considera- 

 ble magnitude ; its wood is aromatic, compact in its texture, 

 of a brownish colour, and its root abounds with essential 

 oil. This tree, which is found in the vast forests which cover 

 the flat and fertile regions between the Oronooko and the 

 Panine, has from an analogy already alluded to been sup- 

 j)osed to belong to die natural order Laiiri ; and though 

 Humboldt and Bonpland do not seem to have been acquainted 

 with its singular and important produce, its botanical cha- 

 racters may very possibly have been described in their Plantce 

 Equinoctialcs under the genera Ocotea, Persea, or Litsea. 

 This question, however, I am unable to solve, as I have never 

 seen the parts of fructification. 



" The native oil of laurel is produced by striking with an 

 axe the proper vessel in the internal layers of the bark, while 

 a calabash is held to receive the fluid. So obscure, howevei', 

 are the indications of these reservoirs, that the Indians (with 

 perhaps a little of their usual exaggeration) assert that a per- 

 son unacquainted with the art may hew down a hundred 

 trees without collecting a drop of the precious fluid. In many 

 of its properties the native oil resembles the essential oil ob- 

 tained by distillation and other artificial processes : it is, how- 

 ever, more volatile and highly rectified than any of them, its 

 specific gravity hardly exceeding that of alcohol. When pure 

 it is colourless and transparent ; its taste is warm and pun- 

 gent; its odour aromatic, and closely allied to tiiat of tlie oily 

 and resinous juice of the Conferee .- — so striking is this resem- 

 blance, that a friend to whose inspection I submitted the oil 

 pronounced it rather hastily to be s|)irits of Uupentine. It is 

 volatile, and evaporates without residmun at the atmospheric 

 tfuiperature. Jt is inflammable, burning entirely away, and 



except 



