180 Dreiu, Green and <S7. John : 



is determined l)y the resorcin method in the middle fractions hoilinj? 

 from 170 deg. to 190 deg., and the highest fractions are utilised for 

 the estimation by hydroxylamine of aromadendral and associated 

 aldehydes. The optical rotation of tlie middle fractions gives a 

 measure of the phellandrene content of the oil, when a qualitative 

 test has shown it to be present. 



Baker and Smith^ discovered that if the leaves of E. ittdcrorhynrlui 

 ' be extracted with boiling water, a considerable amount of a yellow 

 dye, which they isolated and mimed myrticolorin, was obtained. 

 This is an important character in the comparison of the stringybarks, 

 and we have readily confirmed their observation, but find little oi 

 none of the dye to be present in the leaves of either E. ConndeniaiKi 

 or of E. MjieUeriana. 



Five different distillations of oil, from four trees of widely varying 

 ages, were examined, and the results are <riven in Tables T. and II. 

 Nos. I., II. and III. are from trees growing within a quarter of a mile 

 of one another between Eltham and Greensborough. No. IV. was 

 taken from a tree on similar country between Lilydale and Evelyn. 



The differences in percentage yield are very marked, but are in 

 accord with the variations in this respect observed in several species. 



The optical rotation, however, also shows considerable fluctuations 

 fi-om tree to tree : the chemical significance of this variable rotation 

 is not quite clear, owing to the impossibility of accurately determining 

 the amount of phellandrene present. It has been suggested that the 

 optical rotatory power of /-phellandrene is not a constant. 



Chemical tests showed that the oil consisted mainly of phellan- 

 drene and aromadendrene with about ten per cent, of eucalyptol and 

 small amounts of aromadendral. 



TABLE I. 

 Physical Constants of Oils from the Lkave.s ok Exruhjidug Couitidoiiana. 



p . Volumes so per 



.^pprox. Affe Date of 5.',,. cent, alcohol Siiecifio Optical Refractive 



of tree. '^ distillation. '^'';": ','?'' dissolving one jiravity. rotation. index. 



•^"^'*^- voluniLoil. 



la. - 20-30 years - July, 1911 - 0.55 - insolnlile - .876 - - UXf - 1.1795 



lb. - ,, „ - Oct., „ - ().5() - insoluble - .S71 - -49.4° - 1.4790 



II. - 70-100 years - Sept., „ - 0.(15 - 1 v..l. - .880 - - 3t;.;r - 1.4790 



III. - 100-150 voar.s - Oct., ,. - 1.05 - 2 vols. - .89B - -23.5" - 1.4S37 



IV. - 50-70 years -July, ,. -0.20- 1^ vols. -.905- -17.3^- 1.1804 



T.VI5LK II. 



Chemical Propkrtiks of Oils from the hv.WKfi of Eucalyyt'ns Consideniana. 



1 .. 1 .111 Volatile Higher i.'„t .... 



Kucalyptol. Alcohol. aldehvdes. aldehvdcs. ''-'"■'• 



I.i - «-7( . •««> . 17 - 14 - 2 7 



^'^- 9.6 S .83 s ' 



Ih. - - - . _ . 1.2 



''• 2.50) 2.1) 



III. - 7.5 - — - 0.5 - — - 1.(5 



We were unable to detect pinene or endesmol in any sample. 



1. Smith, Jonrri. Chem. Soc. (1898), 73, 697. 



