98 ON THE OLEO-RESIX OF CAXARIUJI MUELLEEI, ETC., 



stance ; it has the same properties as Balsam of Copaiba." 

 (Lindley, quoted in Drury's I'st'tnl PlKutsof Indid). 



These three statements of old authors form the basis on 

 which nine-tenths of subsequent notes on the resin are made in 

 books. It is a reflection on botanists — (1) That the nature of 

 the resinous exudation of so common a tree as C. comninnc is not 

 placed beyond doubt ; and (2) that the source of Manila Elemi is 

 not settled absolutely. 



The most recent note of all is : — ■" The resin of (J. connimne 

 occurs in large dry masses of a yello^Yish-\vhite colour ; it readily 

 softens when heated, and has then an odour like Elemi," Plumu. 

 Indicd, Pt. II. I hope to soon see a fuller examination of this 

 resin, i.e., the indubitable product of Cun/iriitiii cnwuinue. 



Part II. 



The oleo-resin of CannriiDn Miwllcri is readily soluble in 

 light petroleum, chloroform, ether, absolute alcohol, rectified 

 spirit {.S-ii'S sp. grs.), but only partially so in 50 per cent, alcohol. 



If exposed to the atmosphere the oleo-resinjsteadily diminishes 

 in intensity of odour, while the viscosity increases. The 

 following are the results of an actual experiment : — A quantity 

 of the oleo-resin was exposed to the atmosphere on the 18th 

 April ; on the 7th May it had lost 3.331 per cent in weight ; on 

 the 7th July 5.531 per cent., and on the 10th October over 7.105 

 per cent. There is no doubt that if exposure to the atmosphere 

 be maintained for a sufticiently long period, the residual 

 substance would become brittle and destitute of odour. 



If the exudation be treated with dilute alcohol, and exposed 

 to the heat of a water bath, a volatile oil is driven oft" which may 

 be condensed and separated from the accompanying alcohol 

 without much difficulty, while a resin is left behind. The 

 whole of the volatile oil is with difficulty driven off at this tem- 

 perature within a reasonable period, unless solution in alcohol be 

 effected ; the operation may be expedited by means of an air- 

 bath (temperature 110'-120= C). 



When cold the residual resin is beautifully transparent, and 

 of the colour and general appearance of gelatine. The con- 



