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XXXVI. On the Constitution of BebeermPT Bi/ Douglas 

 Maclagan, M.D., F.R.S.E., and Thomas G. Tilley, 

 Esq.) Professor of Chemistry in the Qtieen^s College^ Bir- 

 mingham^. 



"DEBEERINE is the name given by Dr. Rodie of Deme- 

 ■^ rara to an organic base, of which he pointed out the 

 existence, in the bark of a tree of that colony known by the 

 names of Beheeru or Green heart. This tree has recently been 

 examined botanically by Sir Robert Schomburgk, and found 

 to be a species o{ Nectandra, which in compliment to Dr. Rodie 

 he has named N.Rodiei (Hooker's London Journal of Botany, 

 December 1844-). 



The general properties of the alkali, and the preparation of 

 its sulphate for medicinal use, were further described by one 

 of us in a paper read before the Royal Society of Edinburgh 

 in April 1843 (Transactions, vol. xv. part iii.). In this me- 

 moir an account was given of the preparation of bebeerine, in 

 what was regarded as a state of chemical purity, and of its 

 separation by means of aether from what was believed to be 

 another alkaline matter, sipeerine; but as the substance is 

 neither crystallizable nor colourless, it could not decidedly be 

 affirmed to be chemically pure until its constitution had been 

 determined by ultimate analysis. This desideratum it is pro- 

 posed to supply in the present paper. 



The chief difficulty in preparing the pure alkali arose from 

 the troublesome process required to free it from adhering 

 tannin, considerable loss being experienced in the methods 

 then adopted. This has subsequently been accomplished with 

 greater facility by the following process, which may be appli- 

 cable to the purification of other organic bases. 



The sulphate prepared for medicinal use, which is always 

 more or less impure, is precipitated by ammonia; and the al- 

 kaline matter thus sepai'ated, is, after washing with water, tri- 

 turated with about an equal weight of freshly precipitated and 

 moist hydrated oxide of lead. The magma thus formed is 

 then dried over the water-bath, and the alkali is taken up by 

 absolute alcohol. On distilling off the spirit, the organic base 

 is left in the form of a transparent orange-yellow resinous 

 mass, as described in the paper above quoted. This, on being 

 dried, pulverized, and treated with successive portions of pure 

 aether, is in great part dissolved in this fluid. The dissolved 

 portion, on distilling off the aether, is obtained in the form of 

 a translucent, amorphous, but homogeneous resinous-looking 

 substance, of a pale yellow colour, and possessed of all the pro- 



* Communicated by the Authors. 



