December, 1910.] 



491 



Oils and Fats. 



this respect resembles No. 7*. The yield 

 of the oil in this distillation was 0"20 

 per cent. 



No. 6. 



Quantity : 134 cc. ; distilled July 6 and 

 September 23, 1907. 



Description: Pale yellow oil with a 

 pleasant odour. A slight deposit was 

 present. 



Results of Examination. 



Specific gravity at 15715° C = 913. 



Optical rotation in 100 mm. tube at 

 21° C = + 12° 12'. 



"Total alcohols-" (gerauiol and citro- 

 nelal) = 46*5 per cent. 



Geraniol = 29'3 per cent. 



Citronellal = 17"2 per cent. 



Solubility in alcohol : gives a clear 

 solution with its own volume of 80 per 

 cent, alcohol, but becomes opalescent 

 with 10 volumes. 



Remarks.— This oil was distilled from 

 " glaucous-leaved mana grass," identified 

 by Dr. Stapf as Cymbopogon Nardus, 

 Rendle, var. confertiflorus, Stapf, which 

 is also the source of the oils of groups 

 3 (?), 7 and 8. The yield of oil in this dis- 

 tillation was H'44 per cent., which is 

 much higher than that obtained in any 

 distillation of the grasses Nos. 3, 7, or 8. 



No, 6*. 



Quantity : 126 cc. ; distilled August 21, 

 1908. 



Description : Pale yellow oil with a 

 pleasant odour, more pungent than that 

 of No. 6. A slight deposit was present. 



Results of Examination. 

 Specific gravity at 15715° C = 0'900. 

 Optical rotation in 100 mm. tube at 

 21-5° C = + 4°0\ 



"Total alcohols " (geraniol and citro- 

 nellal) = 61 '2 per cent. 



Geraniol = 43*7 per cent. 



Citronellal = 17*5 per cent. 



Solubility in alcohol : gives a clear 

 solution with its own volume of 80 per 

 cent, alcohol, but becomes opalescent 

 with 10 volumes. 



Remarks.— This oil is from the same 

 source as No. 6. The percentage of " total 

 alcohols " is considerably greater than in 

 No. 6, owing to the increase in the 

 amount of geraniol. The yield of oil on 

 this occasion was 0'2o per cent., a con- 

 siderable reduction as compared with 

 the previous distillation. 



No. 7. 



Quantity : 246 cc. ; distilled July 2 and 

 September 24, 1907. 



Description : Golden yellow oil, having 

 a pleasant, not very pungent, odour. A 

 slight deposit was present. 



Results of Examination. 



Specific gravity at 15°/15° C = 0'908. 



Optical- rotation in 100 mm. tube at 

 22° C = + 1° 27'. 



" Total alcohols " (geraniol and citro- 

 nellal) = 54*8 per cent. 



Geraniol = 30'2 per cent. 



Citronellal = 24'6 per cent. 



Solubility in alcohol : gives a clear 

 solution with its own volume of 80 per 

 cent, alcohol, but becomes slightly opal- 

 escent with 10 volumes. 



Remarks.— This oil is derived fiom 

 " white-stemmed mana " grass, which has 

 been identified by Dr. Stapf as Cymbo- 

 pogon Nardus, Rendle, var. confertiflorus, 

 Stapf. The yield in this distillation was 

 0*24 per cent., which is much lower than 

 that obtained from the first distillation 

 of grass No. 6, which is regarded as the 

 same species. The oil, moreover, differs 

 somewhat markedly from Nos. 6 and 6* 

 in the relative amounts of geraniol and 

 citronellal present. 



No. 7*. 



Quantity : 104 cc. ; distilled August 12, 

 1908. 



Description : Dark coloured oil, with a 

 somewhat pungent and slightly " burnt" 

 odour. A considerable deposit was pre- 

 sent. 



Results of Examination. 



Specific gravity at 15° /15* C = 0-904. 



Optical rotation in 100 mm. tube at 

 22-5° C = + 2° 26'. 



" Total alcohols " (geraniol and citro- 

 nellal) 58'0 per cent. 



Geraniol = 24 '8 per cent. 



Citronellal = 33'2 per cent. 



Solubility in alcohol: gives a clear 

 solution with its own volume of 80 per 

 cent, alcohol, becoming opalescent .vith 

 10 volumes. 



Remarks.— This oil is from the same 

 source as No. 7. The yield in this distil- 

 lation was 0-11 per cent., which is a con- 

 siderable reduction on the result of the 

 previous distillation. The percentage of 

 " total alcohols " has increased, with a 

 large increase in citronellal and a de- 

 crease in geraniol. 



No. 8. 



Quantity : 77 cc ; distilled July 1 and 

 September 25, 1907. 



Description : Yellow oil having a plea- 

 sant, not very pungent, odour. A slight 

 deposit was present in the bottle con- 

 taining the oil. 



