ANALYSIS OF A GUM-RESIN FROM MADAGASCAR. \^.^ 



separates immediately on cooling. The matter that thus ^ 

 falls down in cooling exhibits all the properties of lac. Its 

 weight is six hundredths of the resin. 



The portion of the resin, one tenth, on which the alcohol 

 bad no action, was treated with caustic potash dissolved in 

 water. This had not much more action on it than alcohol ; 

 leaving it in the form of a brown powder, soft to the touch, 

 and still weighing near one tenth. 



This substance, insoluble both: in alcohol and potash, 

 was distilled with a gentle heat. At first it gave out a little 

 water; and then vapours arose, which condensed into an 

 oil, and a liquid of a taste somewhat aromatic, without 

 being disagreeable, having a great resemblance to the pro- 

 duct of gums. 



None of the products of this distillation, mixed with 

 quicklime or with potash, yielded the least trace of ammo- 

 nia. The coal in the retort was easy of incineration, and 

 left a decigramme of yellowish ashes, containing some lime, 

 and a little oxide of iron. 



The alcoholic solution of the resin had a brown colour 

 and a peculiar taste. Being evaporated to dryness in a 

 retort, the alcohol that came over contained nothing aro- 

 matic. 



The resin was boiled in water, to which it communicated 

 a slight taste. Thus purified- it had a yellowish brown co- 

 lour. It retains water pretty strongly, for it is difficult to 

 dry, and remains soft a pretty long time. 



Thus it appears, that the substance which we have called Component 

 a gum-resin contains, in 10 grammes, f nrts ' 



1, Lac 06 



2, Residuum, containing a little more 



lac and vegetable matter 1*0 



3, Remains for the weight of the resin • • 8*4 



10. 



This is I believe the first time, that lac has been found One plant 

 mixed with other resins; and this fact confirms us in the [^Jnt 'resins 

 opinion, that the same vegetable may form several kinds of and different 

 resins, as well as different trees produce the same resin. sam^resifl 



Vol. XXXII, June, 1812. L Sect. 



