_ 6 9 - 



an aldehyde content ot 75%> and showed the difficult solubility 

 characteristic of the West Indian oils. For the purpose of comparison, 

 an East Indian oil of approximately the same aldehyde-content was 

 taken. The fractional distillation showed that the West Indian oil 

 contained more low-boiling portions than the East Indian oil, for 

 while the latter only commenced to boil above 2 1 o°, 23 °/ of the 

 West Indian oil had already passed over up to that temperature. 

 A comparative distillation at reduced pressure, in which the oils were 

 split up into fractions of 2O°/ each of the quantities employed, showed, 

 moreover, considerable differences in the corresponding fractions, 

 particularly with regard to the optical rotation, inasmuch as from the 

 West Indian oil only inactive fractions were obtained, whilst those 

 of the East Indian oil rotated between — 12 and — 2 . From various 

 observations made by them in the aldehyde - determination by the 

 bisulphite method, Umney and Bennett come to the conclusion 

 that the portions of the West Indian lemon grass oil passing into the 

 bisulphite do not consist merely of citral, and they propose to make 

 a further publication on the subject at a later date. 



We would here point out that according to our observations made 

 both with East Indian and West Indian lemon grass oils, the aldehyde- 

 content ascertained by the bisulphite method is always higher than 

 the one found be the sulphite method. This difference, as we found 

 by experiments, is explained in the case of the East Indian oil by 

 this, that here, by means of sodium bisulphite, along with the citral 

 also other aldehydes 1 ) and further a portion of the methyl heptenone 

 are included, whilst neutral sodium sulphite only reacts with the citral. 

 In the case of the West Indian lemon grass oil the conditions are 

 in all probability precisely the same. There is, therefore, every reason 

 why Burgess 2 ) in a notice dealing with the above work, advocates 

 the use of Sad tier's sodium sulphite method in the manner modified 

 by him 3 ). On the other hand, we are unable to agree with the view 

 expressed by Umney and Bennett 4 ) according to which the citral- 

 estimation is best carried out by titration in the manner proposed by 

 Sad tier; according to our experience this latter method gives no 

 reliable results. 



The cultivation of lemon grass* in the Malay Peninsula. 



The high prices which have lately been paid for lemon grass oil 

 have induced The Times of Malaya to advocate the cultivation of 



*) Report October 1905, 44. 



2 ) Chemist and Druggist 70 (1907), 242. 



8 ) With regard to the most suitable manner, comp. Report April 1905, 103. 



4 ) Chemist and Druggist 70 (1907), 313. 



