December, 1910.] 



499 



Oils and Fats, 



Results of Examination. 

 Specific gravity at 15715° C =0-916. 

 Optical rotation in 100 mm. tube at 

 20° = + 0° 35'. 



Citral, by sodium bi-sulphite method 

 = 67*5 per cent. 



This oil, as in the case of No, 19, was 

 also examined as a citronella oil. The 

 following figures were obtained :— 



" Total alcohols " (including gera- 

 niol) = 58"5 per cent. 



Geraniol = 2*3 per cent. 



Solubility in alcohol : gives a clear 

 solution in 2*2 volumes of 70 per cent, 

 alcohol. Easily soluble in all propor- 

 tions of 80 and 90 per cent, alcohol. No 

 opalescence appears with 10 volumes of 

 alcohol. 



Remarks, — It will be noted that this 

 oil differs very markedly from No. 19, 

 and has assumed the soluble lemongrass 

 type. It seems likely that the grass ori- 

 ginally used by Mr. Jowitt was a mix- 

 ture of a "mana" grass with true 

 Cymbopogon flexuosus, and that on 

 further cultivation the latter suppressed 

 the "mana" grass to a large extent, so 

 that in the second distillation almost 

 pure Cymbopogon flexuosus grass was 

 used. The oil, as received, is a rather 

 poor sample of " soluble "lemongrass oil, 



The yield of oil obtained in this dis- 

 tillation was 0*31 per cent. 



Remarks on the Lemongrass Oils. 



These oils are represented by groups 

 Nos. 13 and 19. The first of these is 

 yielded by Cymbopogon citratus, and 

 the three oils Nos. 13, 13a, and 13 * 

 are typical so-called "soluble" lemon- 

 grass oils of the kinds now produced 

 in the West Indies, Uganda, and else- 

 where. Group No. 13 is therefore of es- 

 pecial interest as confirming Dr. Stapf's 

 statement (see Kew Bulletin, 1906, p, 335) 

 that Cymbopogon citratus is the source 

 of the so-called " insoluble " lemongrass 

 oil. Group No. 19 is abnormal, as noted 

 on the schedules relating to oils Nos. 19 

 and 19*. No. 19* is mostly composed of a 

 soluble lemongrass oil, and it may be 

 supposed that the grass from which it 

 was distilled was mainJy C. flexuosus, 

 though the oil contains a rather low per- 

 centage of citral for a C. flexuosus oil. 



If the cultivation of Cymbopogon 

 grasses is continued at Bandarawela, it 

 would be worth while to extend the 

 experiments suggested for citronella 

 grasses (see p. 40) to the two lemon- 

 grasses from which these oils were dis- 

 tilled. 



The oils of group 13 would probably 

 be worth about 2\d, per ounce under 

 present conditions. Nos. 19 and 19* are 

 abnormal, as already indicated, and do 

 not represent products of commercial 

 interest. 



Note by Mr. J. F, Jowitt. 



The plants from which oils No. 19-19* 

 were distilled were obtained from the 

 sub-division of the only surviving plant 

 out of four, kindly sent to me by 

 Mr. H. H. Hall, of Cottengady estate, 

 Palghat, South India, as the source of 

 Malabar Lemongrass Oil, 



No. 19 oil was distilled in August, 1907. 



No. 19* oil was distilled in August, 1908, 



Both oils were distilled from grass from 

 the same plot. Can the difference in 

 the analyses be due to the age of the 

 grass? Vide Circular, Vol. IV., No. 14, 

 pp. 112-118. 



The herbarium specimen collected was 

 persumably a vagrant plant of Cymbo- 

 pogon Nardus, Rendle. var. conferti- 

 florus, Stapf, Possibly self-sown. The 

 plants were transferred and are now 

 growing at the Experiment Station, 

 Peradeniya ; they were not in flower 

 when I was there on September 8, 1910, 

 but the barren shoots differ from any 

 Cymbopogon that I am acquainted with. 



At the junction of the blade and 

 sheath on the dorsal surface there is a 

 well defined ridge of hairs ; these hairs 

 increase in length as they approach the 

 auricles, where they are of considerable 

 length. 



Auricles thin, rounded, eiliate. 



Midrib underneath ligule hairy. 



I hope to forward herbarium specimens 

 of inflorescence from the Experiment 

 Station plot of grass for identification, 

 and a sample of the oil will be sent to 

 the Imperial Institute. 



John F. Jowitt. 



October 29, 1909. 



Results op the Examination oe 

 Cymbopooon Polyneuros Oil from 

 Ceylon. 



Imoerial Institute No, 26,033, dated 

 July "23, 1910. 



Reference: Letter dated October 13, 

 1908, from Mr. J. F. Jowitt, of Bandara- 

 wela, Ceylon. 



No. 16, 



Quantity : 245 cc. ; distilled June 5, 1907. 



Description : Dark reddish brown oil, 

 having a peculiar sweet penetrating 

 odour quite unlike that of citronella or 

 lemongrass. A very slight deposit was 

 present in the bottle containing the oil, 



