Hi;nky and Flood — 7'Ac Dotujlas Firs. 89 



" 2. 50 lbs. of leaves of old trees growing at Buckhold, Berks, sent in 

 November, when distilled, yielded Oil jior cent, of oil, having the 

 following characters : — 



Specific gravity, .... 0'876 



Optical rotation, . . . . - 7° 



Eefractive index (20°), . . . l-48o5 



Esters as bornyl acetate, . . . 12'4 per cent. 



" The ester-content is much lower than that of the Colorado Douglas 

 Fir oil, but the odour is more fragrant. The oil contains dipentene or 

 limonene, but if pinene is present, the quantity is very small, as practically 

 nothing distils below 175°. 



" 3. A few days later another oO lbs. of leaves of the Oregon Douglas 

 Fir from Buckhold were distilled, and enough oil was then available for 

 further investigation. On fractionating the oil, an appreciable quantity 

 of geraniol was separated, and this appears to be the chief odorous con- 

 stituent. The proportion of total alcohols by acetylation, calculated as 

 geraniol, is '-iVo per cent. The presence of bornyl acetate somewhat masks 

 the odour of geraniol in the original oil. There is also a small trace of 

 citral, but the proportion is too small for determination. 



" Geraniol occurs in tlie oils of some species of Callitris in Australia, 

 but has not been apparently recorded as a constituent of the oils distilled 

 from other conifers. Geranoil is the chief constituent of Indian palmarosa 

 oil obtained from the fragrant grass, Andropogon Schoeiianihiis, and occurs 

 in citronella oil, otto of roses, lemon oil, etc. 



" Colorado Bo\ujlas Fir. 



" 50 lbs. of leaves of moderate-sized trees growing at East Liss, 

 Hants, sent in October, yielded on distillation 0"ol per cent, of oil. 



Specific gravity, .... 0-905 



Optical rotation, .... - 46" 



Eefractive index (20=), . . . 1-4717 



Esters as bornyl acetate, . . . 34-5 per cent. 



" The terpenes consist principally of pinene. The odour is chiefly due 

 to the bornyl acetate present. 



" It would appear from these analyses that the strong odour of 

 Colorado Douglas Fir, which is like that of turpentine mixed with 

 camphor, is due to the large percentage of pinene and bornyl acetate. In 



