450 oi)OKO(;raphia. 



272^, and presenting characters which show that it is identical 

 with the product from Sumatra benzoin. Siaresinotannol, 

 CjoHj^Ogjis also an alcohol having the form of a brown powder 

 free from taste and smell, differing in composition from resino- 

 tannol of Sumatra benzoin, but analogous to it in most of its 

 characters.* The general result of these ol)servations is that both 

 Sumatra and Siani benzoin consist chiefly of mixtures of benzoic 

 esters of resinoid alcohols, together with 1-6 per cent, free benzoic 

 acid and some vanillin. 



The bark of Styrax Benzoin, Dryander, contains, besides traces 

 of wax, some phloroglucin and sugar, a large amount of tannin, 

 which is readily convertible by oxydation into its phlohcq?hcn, 

 corresponding with the formula C^^^H.qOoi, and Ludy is of 

 opinion that this is the source from which benzoin is produced. 



Cajuput. Alalalcuca ciridifolia. This myrtaceous tree has 

 been found growing in great abundance in Xew Caledonia. Its 

 leaves, when fresh, yield on distilhition with water, about 2-5 per 

 cent, of their weight of a pale yellow oil, known as " Essence de 

 Niaoidi" of which the odour recalls that of cajuput. This oil has 

 been examined by G. Bertrand, who describes itf as having a 

 density of 0-922, and a rotatory power of + 0^ 42'. By adding to 

 it successively solutions of potash and of sodium bisulphite, and 

 resorting to saponification, the presence of a trace of valerianic 

 acid was indicated, as well as small proportions of benzoic aldehyde 

 and valerianic ether. On distilling, four-fifths of the oil pass over 

 below 180°, which may l)e divided into two fractions, one of 

 which boils at lo5°-156°, and the other at 173^-175°. The first 

 is a terpene, having, after distillation with sodium, a density of 

 0-865 and rotatory power + 36^-03 '. Its formula is C, ^ H^ g, and 

 with hydrochloric acid gas it forms a crystalline monochlorhydrate, 

 having, in alcoholic solution, a rotatory power of + 2;j°-09'. The 

 second fraction is a mixture from which, at a temperature below 



* Siaresinotannol yields a jtotassiuni derivative, CioHj., O.. K+ H., O, 

 crystallisin.f,^ in yellow needles, and an acetyl derivative, C12 H^y Ac O3, as 

 a yelloAv amorphous powder. 



t Coniptes Rendus, cxvi., p. lOTO. 



