Commercial notes and scientific information. 



71 



East, and the number of samples examined was much too large to admit of such an 

 explanation. Moreover, not only the East Indian but also the West Indian oils showed 

 a diminution in solubility. He leaves it an open question whether this is an accident 

 or whether it is connected with the drop in the citral value. 



What surprises us in Parry's discovery is that in no case has he found the 

 difference to exceed 5 p. c. From this it would appear that the drop in citral value 

 is very soon arrested, possibly because the products which are formed in the process 

 of alteration of the constituents of the oil have a preserving effect upon the citral. 

 We may add that a sample of lemongrass oil from Barbados, which is described 

 in our Report of November 1908 (p. 82) was found by us after a lapse of 2 years to 

 have the same aldehyde-content as when we first examined it (85,5 p. c. with neutral 

 sulphite or 90,5 p. c. with bisulphite). In this case also there was no change in the 

 conditions of solubility, which appears to support the supposition that diminution of 

 solubility goes hand in hand reduction of citral value. 



In our Report of April 1912, p. 89, we mentioned several samples belonging to the 

 group of sparingly-soluble lemongrass oils, which had been examined by the Imperial 

 Institute of London. Among other places, these oils came from Ceylon and British 

 India (Wahjain, Prov. of Assam). Since then the Imperial Institute 1 ) has received from 

 the same districts fresh samples of lemongrass oils of which the constants were 

 similar to those previously examined. With 70 p. c. alcohol the samples gave no clear 

 solution. For the rest their behaviour was as follows: — 



Origin. 



Citral content 

 (Bisulphite method) 



Ceylon . . 

 India, Tyrna 

 India, Cochin 

 India, Mariani 



0,9109 

 0,9039 

 0,9035 

 0,8973 



0°30 f 

 0°40' 

 0°20' 



73,7 p. c. 

 72,2 „ 

 81,5 „ 

 78,0 „ 



Another example of the sparingly-soluble lemongrass oils is represented by a 

 distillate from Burma described in the Perfumery and Essential Oil Record 2 ). This 

 sample was soluble in 90 p. c. alcohol with slight opalescence; sp. gr. 0,893 (15°); 

 citral-content 74 p. c. The author of the article in the journal in question expresses 

 the surmise that the imperfect solubility of the oil is due rather to the conditions of 

 the weather prevailing during the cutting of the grass than to differences in the actual 

 species of the grass from which the oil was distilled. He bases this view upon the 

 fact that the yield of oil from the grass is less during the dry than during the rainy 

 season, and he expresses the hope of being able to give further particulars on this 

 subject, because he has been promised samples of oil distilled under both conditions. 



Together with the oil above-mentioned, the author describes two other samples, 

 also Burmese; the product of "sweet-scented lemongrass". This oil, in its general 

 characters, is more akin to Java citronella oil. Of the two samples one had sp. gr. 

 0,893, total geraniol-content 91,5 p. c. while in the other (di 3 o 0,896) the total content of 

 acetylisable constituents was estimated at 101,5 p.c. It was also found that the proportion 

 of citronellal in the second sample very considerably exceeded that of the geraniol. 



l ) Bull. Imp. Inst. 10 (1912), 546. 



! ) Perfum. and Essent. Oil Record 4 (1913), 3. 



