I 1 " 



alcohol was not available with which to prepare the calcium salt, bul its odour, 

 as well as tint ot its ethyl ester, was identical with those prepared with the a< id 

 of the ester, and also corresponded with similar substam es m ide with pure normal 

 butyric acid. 



The greater portion i>t the total esters in the oil oi E. Perriniana appears 

 to be the low boiling butyl-butyrate ; tins is shown from the sa] onification results 

 with the freshly distilled oil. The saponification number for the crude oil was 

 52-(>, representing I.V52 per cent, oi an ester having a molecular weight 144. 

 The saponification number for the portion distilling 1 clow [go C. 75 per ceni 

 was 57-. representing 14-7 per cent, of ester in this traction. The ester was nol 

 decom; osed on direct distillation, as no free a« id was detected in the lower boiling 

 fractions. 



It might be well in future analyses of Eucalyptus oils, distilled from trees 

 belonging to this groups to determine the saponification number for the ester in 

 the lower boiling fraction, particularly when the ester value for the crude oil is 

 at all high. 



On the completion of the work on the ester in the oil oi E. Perriniana 

 from New South Wades, one naturally returned to the oil of this species 

 previously distilled from Tasmanian trees, the fractions of which had been 

 preserved. The first fraction, representing r8 per cent, of the crude oil, 

 distilling below 173 C, contained a little free acid formed by the natural 

 hydrolysis of a portion of the ester. The saponification number for the ester 

 and free acid in this fraction was 45-8. This result shows the ester in the oil oi 

 E. Perriniana of Tasmania to be a low boiling one, and also that the greater 

 portion distilled over in the first fraction, as was the case with the oil of the 

 New South Wales material. 



The Valeric Acid Ester occurring in some 



Eucalyptus Oils. 



It has been shown (see tabulated list) that esters, either in large or small 

 amounts, occur in all Eucalyptus oils, varying from 60 to yy per cent, oi 

 geranyl acetate, in the oil of E. Macarthuri, to very minute quantities in such 

 oils as E. dives, E. radiata, E. Smithii, &c. The amyl-estei of eudesmic acid 

 occurs in some quantity in the oil of E. aggregate/, and in the oil of E. carnea an 

 acetic acid ester has been determined see under that species . Butyl-butyrate 

 is also a frequent ester in Eucalyptus oils of a certain class. The constituents ot 

 these four esters did not, however, explain the presence of a volatile acid 

 resembling valeric acid, which constituent had often been detected in the oils oi 

 several species, and m those oi E. saligna var. pallidivalvis, E. cinerea, E. gonio- 

 calyx, E. Maideni, E. botryoides, &c, the presence oi a considerable amount of 

 ester had been determined. The product oi E. saligna var. pallidivalvis appeared 

 to be the best for the determination of this valeric acid ester, because the acid 

 was so well demonstrated, and the amount of ester in the oil comparativelj 

 large. 200 c.c. of the oil of this species, collected at Lismore, New South Wales, 

 in May, 1898, were boiled for some hours with aqueous potash, under a reflex; 



