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Seen to be built up by the accumulation of longitudinal filiments, and when 

 crushed can be separated into their component parts, thus showing how loosely 

 they are combined. This is the only instance in which crystals of this character 

 have formed naturally after the eudesmol had liquefied. 



As previously mentioned, this liquid eudesmol can be changed to the 

 crystallised condition, and this result is well shown by the accompanying 

 illustration. The crystals depicted were regenerated from the wholly liquefied 

 form of eudesmol originally prepared from the oil of E. Macarthuri. 



The liquefied eudesmol was dissolved in ether, and the resinous acid 

 portion, which had formed during the alteration, shaken out by aqueous 

 potassium hydrate. The amount of acid substances thus removed was equal to 

 8 per cent. The ether was then evaporated from the liquid eudesmol, which at 

 this stage showed no signs of crystallisation, and the residue sublimed on the 

 water bath. A considerable portion was thus obtained in the crystallised 

 condition, as depicted in the illustration. Under the microscope these crystals 

 were seen to be identical with those formed naturally, and although less stout, to 

 have been built up in a similar manner. 



Unlike the originally crystallised eudesmol, these sublimed composite 

 needles did not polarise at all well, but if melted, and again allowed to crystallise, 

 they showed the same peculiarities of crystallisation and polarisation as in the 

 case of the original eudesmol under similar conditions. Radiated masses of 

 crystals in all cases gave well defined dark crosses similar to those shown by 

 uniaxial crystals when observed under crossed nicol prisms. 



The melting point of the sublimed crystals, derived from the liquid form, 

 was some degrees lower than that of the original eudesmol ; but in this respect 

 there was little uniformity, as those which sublimed at the top of the covering 

 dish, or furthest from the subliming material, melted at 74-76 C., while those 

 formed nearest to it melted at 65-72 C. The slight amount of impurity present 

 in the sublimed crystals was thus sufficient to lower their melting point, because 

 when the whole was purified by recrystallising from alcohol, the melting point 

 was that of the original eudesmol, 79-80 C. 



The liquid residue, separated from the acid bodies as described above, was 

 therefore shown to be eudesmol, and this conclusion was also supported by the 

 formation of the acetate in almost theoretical amount on acetylation, as well as 

 by the character and behaviour of the crystals formed by sublimation, and their 

 microscopic appearance. 



That eudesmol occurs naturally in the liquid form in some Eucalyptus oils 

 is perhaps best shown with that of E. Rossii, and in no case has crystallised 

 eudesmol been detected in the oil of this species under natural conditions 



In the first edition of this work, page 71, we describe the oil of E. Rossii 

 from two localities in New South Wales (Bathurst and Bungendore), and show 

 the presence of a highly dextro-rotatory constituent in the higher-boiling portions 

 of both, that from Bathurst being + 19-19, and the other almost as high. 

 These samples were mixed and stored in the dark, and twenty years afterwards 

 the oil was again analysed. The highly dextro-rotating constituent, when finally 

 distilled under reduced pressure at 10 millimetres, slowly crystallised and was 

 found to be eudesmol melting at 79-80, and to have specific rotation [] + 

 33-58 in a 12 per cent, chloroform solution. It is thus seen that the liquid form 

 of eudesmol is an exceedingly stable substance, particularly as it was somewhat 

 readily separated in the crystalline condition after the lapse of twenty years. 



We have so far detected either the liquid or crystallised eudesmol in the oils 

 of forty-two species of Eucalyptus, and have prepared the crystallised form in 

 the pure condition from several. It is a coincidence, perhaps, that in twenty-one 



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