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Fennel Oil (Oleum Fceniculi). Colourless or faintly yellowish; di 6 o 0,965 

 to 0,975; « D + 12 to +24°; sol. in an equal vol. of alcohol. When cooled 

 below 0° anethol crystals separate out, which only remelt completely when 

 the oil is heated to +5 to 6 01 ). 



*) It should be noticed that in certain circumstances fennel oil may be strongly cooled 

 without solidifying; but it solidifies at once if a trace of solid fennel oil, Russian anise oil or 

 anethol is added to the cooled oil. The requirement that fennel oil must again be completely 

 melted at 5 to 6 ° is quite untenable, for it would expressly exclude from pharmaceutical use 

 those fennel oils which are the richest in anethol and therefore the best, for such oils only 

 melt above 6° (we have observed up to 10° in our own distillates). The m. p. indicated by 

 the Pharmacopoeia can only be regarded as the lowest permissible. It would have been better 

 if a definite cong. p. (which should not be below -\-S 6 ) had been substituted for the 

 Pharmacopoeia's requirements. 



When fennel oil is imperfectly kept its sol. p. falls, and finally it refuses to solidify 

 altogether. Comp. Report October 1904, 42. 



juniper Oil (Oleum Juniperi). Colourless, pale-yellowish or pale- 

 greenish; diso 0,860 to 0,880°; gives a clear or slightly cloudy solution with 

 10 parts of alcohol. 



Lavender Oil (Oleum Lavandulae). Colourless or faintly yellowish; 

 diso 0,882 to 0,895; « D — 3 to — 9°; linalyl acetate content not less than 

 29,3°/o 1 ); dissolves at 20° in 3 parts of dilute alcohol, making a clear, and 

 sometimes an opalescent, liquid 2 ). 



x ) The time of saponification, according to the general directions of the Pharmacopoeia, 

 is 15 minutes ; in certain conditions this time is insufficient for the quantitative saponification 

 of lavender oil. In doubtful cases it will therefore be well to repeat the experiment, heating 

 for 30 min., for only then is it possible to be certain that all the linalyl acetate which is 

 present has been saponified. 



2 ) This indication is correct for an alcohol of 70 p. c. by vol. ; but of the dilute alcohol 

 of the Pharmacopoeia, up to 4 parts (according to strength) are required for solution. Even 

 the ordinary Pharmacopoeia oils, deficient in ester, only respond to the above demand when 

 the alcoholic strength of the dilute alcohol is near the maximum limit (69 p. c. by vol.). This 

 fact should not be lost sight of in the test. We have repeatedly called attention to this matter 

 in our Reports. Comp. Report October 1901, 35; April 1908, 130. 



Lemon Oil (Oleum Citri). Bright yellow ; di 5 o 0,857 to 0,861 ; « D20O + 58 to 

 + 65°; lemon oil must dissolve clearly, or with only a little flocculent 

 mucus 1 ) in 12 parts of alcohol. 



x ) The wax-like constituents also fail to dissolve in such a mixture. 



Mace Oil (Oleum Macidis). The oil from the arillode or the seed 1 ). 

 Colourless or faintly yellowish; di 5 o 0,870 to 0,930; « D +7 to +30°; 

 soluble in 3 parts of alcohol. 



*) The direction of the 4 th Ed. of the Pharmacopoeia, stating that only the oil from the 

 nutmeg is to be employed for medicinal purposes has rightly been discarded, for up to the 

 present it is impossible to judge either from the constants or the composition of the oil 

 whether it has been prepared from the seed or from the arillode. 



Menthol (Mentholum). Acute, brittle, colourless crystals, barely soluble 

 in water, very readily soluble in ether, chloroform and alcohol; m. p. 44 01 ); 



