— 55 — 



Hop-flower oil has as its principal constituent a sesquiterpene called 

 humulene, which occurs also in oil from the leaf-buds of the black poplar 

 (Popnlus nigra, L.). Deussen 1 ) has recently discovered that this humulene 

 is identical with e-<*-caryophyllene. The author found the substance to 

 occur in the fractions of hop oil boiling between 115 and 140° (8,5 mm.); 

 after repeated fractionation it boiled between 118 and 119° (10 mm.). The 

 nitrosate had m. p. 161°, which was not in the slightest degree depressed 

 with ?-«-caryophyllene nitrosate of the same m. p. The nitrolamine bases 

 of the two compounds were also identical. Humulene nitrosochloride 

 (m. p. 177°) suffered no depression of m. p. with ^-a-caryophyllene nitroso- 

 chloride. Humulene also yielded a scanty proportion of a nitrosite which 

 was not identical with /?-caryophyllene nitrosite, and which may possibly 

 be a derivative of i-«-caryophyllene, the nitrosite of which is as yet 

 unknown. The scarcity of the nitrosite-yield may perhaps be due to the 

 experimental conditions of the method of preparation not having been 

 favourably chosen, or to the presence in hop oil of a small proportion 

 of a second sesquiterpene hydrocarbon in addition to caryophyllene. 



The aliphatic terpene of hop oil has also been investigated recently, 

 Semmler and E. W. Mayer 2 ) having shown its identity with myrcene. The 

 constants of the oil under examination were as follow: d§§0,8781, « D — 0,1°; 

 those of the myrcene-fraction: b. p. 62 to 63° (17 mm.), d 2 oo 0,7937, «±0, 

 n D 1,4716. In order to identify the myrcene the authors prepared dibromo 

 myrcene, dihydromyrcene tetrabromide and myrcenol. 



Hyssop Oil has again been distilled by us from herb grown by 

 ourselves, but the injurious effect of the heat and drought has also made 

 itself felt in this article. We have only a limited stock and it will pro- 

 bably soon be necessary to raise the price. 



Oil of Inula viscosa. From Inula viscosa, Ait. (Cupularia viscosa, Gren. 

 et Godr.; Pulicaria viscosa, Koch; N. O. Composite), which they obtained 

 from Algeria, Roure-Bertrand Fils 3 ) have distilled a pale brown oil, with 

 an odour both of hyssop and of eucalyptus oils. The oil gave the following 

 constants: d 15 o 0,9436, a — 24° 0', sol. in 1 vol. and more 80% alcohol, 

 with separation of paraffin. With 10 vols. 70% alcohol the solution 

 remained slightly turbid. About 70% of the oil were absorbed by a 50% 

 resorcinol solution; hence the principal constituent of the oil appears to 

 be cineol. 



Some years ago, when engaged in distilling the same plant 4 ), we 

 obtained an oil with quite different properties. It was viscous, of a dark 

 brown colour, and even at ordinary temperature paraffin was separated 



2 ) Journ. f. prakt. Chem. II. 83 (1911), 483. 



2 ) Berl. Berichte 44 (1911), 2009. 



') Berichte von Roure-Bertrand Fils, April 1911, 23. 



4 ) Report October 1903, 76. 



