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in carbon disulphide 1 ) ; when 20 drops cajuput oil are shaken with 5 cc. 

 water and 10 drops nitric acid, the mixture must not be coloured blue 

 after an excess of ammonia has been added. 



1 ) All essential oils are soluble in carbon disulphide, and any cloudiness which 

 thereby occurs must be attributed to a slight content of water due to the process 

 of manufacture of the oil. 



Clove Oil (01. caryophyllorum). Brownish 1 ); d 15 o 1,045 to 1 >°7°] 

 boiling point 2.50 to 260 ; soluble in 2 volumes 70 per cent, alcohol; 

 when 5 drops oil are shaken with 10 cc. lime water, a flaky precipitate 

 should be formed, which deposits itself on the walls of the vessel; identity 

 reaction and test for phenol with ferric chloride in the usual manner. 



*) Clove oil has a yellowish colour, but becomes darker with increasing age. 



Fennel Oil (01. foenicuii). Colourless or yellowish; d 15 o 0,965 

 to 0,985; «r> to the right; at -|-3 it solidifies to a crystalline mass 1 ); 

 soluble in alcohol; the solution must be neutral and must not be 

 changed by ferric chloride. 



1 ) Solidification does not occur spontaneously at this temperature, but must be 

 brought about by inoculation with a small crystal of anethol. 



Lavender Oil (01. lavandulae). Colourless or yellowish; d 15 o 0,885 

 to 0,895; ujy to the left; saponification number not below 84 = 29,4 °/ 

 linalyl acetate; soluble in 2 parts 90 per cent., and in 3 parts 70 per cent, 

 alcohol; the oil becomes viscid when exposed to the atmosphere, and 

 then acquires an acid reaction. 



Lemon Oil (01. citri). Clear or slightly turbid; bright yellow; 

 d 15 o 0,855 to 0,865!). 



1 ) The range of this constant is so wide that the majority of adulterated oils 

 will probably, also answer these requirements; in the case of pure oil, the specific 

 gravity ranges between 0,857 and 0,861 (15 ). 



Mace Oil (Ol.macidis). A somewhat viscid 1 ), clear, yellowish liquid ; 

 d 15 o 0,890 to 0,930; «d to the right; soluble in 3 parts qo per cent, 

 alcohol, in an equal volume carbon disulphide; in the last-named case 

 cloudiness occurs when more solvent is added. 



1 ) This statement refers to old, resinified oil; the fresh distillate is a mobile 

 liquid, and colourless or yellowish. 



Menthol. The requirements correspond to those of the German 

 Pharmacopoeia. 



Mustard Oil (01. sinapis aethereum). Colourless or yellowish; 

 d 15 o 1,018 to 1,025; « D +o°; boiling point 148 to 152 ; soluble in 

 every proportion in 90 per cent, alcohol; the further tests also cor- 

 respond to those of the German Pharmacopoeia. 



Peppermint Oil (01. menthae piperitae). Colourless or yellowish, 

 in course of time becoming thicker and darker; d 15 o 0,900 to 0,910; 

 a D to the left; soluble in 4 to 5 parts 70 per cent, alcohol; when 



