DR DUNCAN on Mudarine, 435 



organic principles, and that its discovery may lead to consider- 

 able modifications in our methods of analyzing organic sub- 

 stances. 



Mudarine is very easily obtained, in a state of considerable 

 purity, from the tincture of mudar, made by macerating the 

 powder of the root in cold rectified spirit. The greater part of 

 the spirit may be recovered by distillation, and the remaining so- 

 lution, which acquires a much deeper colour, but remains per- 

 fectly transparent, is then allowed to cool. As the temperature 

 declines, a white granular resin is deposited by a species of crys- 

 tallization, from a transparent coloured solution. The whole is 

 now allowed to dry spontaneously, that all the resin may con- 

 crete. The dry residuum is then treated by water, which dis- 

 solves the coloured portion, and leaves the resin untouched. It 

 is to this principle, dissolved by cold water from the resinous ex- 

 tract, that I have given the name of Mudarine. 



By exposure to the air, it dries readily, forming a mass of a 

 pale-brownish colour, perfectly transparent and homogeneous in 

 appearance, having no tendency to crystallize, but becoming full 

 of cracks, diverging from the centre, exceedingly brittle, and ha- 

 ving no adhesion to the capsule containing it, from which it peels 

 off spontaneously. It has no smell, and is intensely bitter, with 

 a very peculiar nauseating taste. 



It is exceedingly soluble in cold water, at the ordinary tem- 

 perature of the atmosphere. On the contrary, it is insoluble in 

 boiling water. It is also soluble in alcohol, but the power of 

 this solvent is increased by increase of temperature. It is inso- 

 luble in sulphuric ether, oil of turpentine, and olive- oil. 



It is in the solution in water, when nearly saturated, that the 

 peculiar property of mudarine is most easily exhibited. 



At ordinary temperatures this solution is quite fluid and 

 transparent. When heat is gradually applied, already at 74, a 

 change in its constitution begins to be observable, indicated by 



VOL. XI. PART II. 3 I 



