— 131 — 



In view of these circumstances we might have compressed the present 

 review into a reference to our criticism of the previous edition of the 

 Pharmacopoeia, were it not that we prefer, in the interests of the principle 

 at stake, to call attention once more to all the mistakes and insufficien- 

 cies of the separate articles enumerated. 



Anise oil (Oleum Anisi). Colourless or pale yellow: di 5 o 0,980 

 to 0,99c 1 ); « D not to the right; solidifies below 10° into a crystalline mass 

 which deliquesces again at + 17 to'+21° 2 ), soluble in 2 to 3 parts of 

 90% alcohol; the solution should be neutral and may not acquire a violet 

 colour with ferric chloride; for medicinal purposes, anise oil with a high- 

 er solidifying and melting point (-j- 15 to 21° and 22° respectively), is 

 admissible 3 ). 



x ) As anise oil occasionally solidifies of its own account at about 17°, it is advisable 

 to take the sp. gr. as about 20°; the limits of value remain unchanged. 



2 ) This indication is quite obscure and would have been better replaced by the require- 

 ment of a definite solidifying point, which, in the case of a good anise oil, is not below -\-\7°. 

 To estimate the sol. p. the oil should be cooled below sol. p. to about 12°, and solidification 

 induced by inoculation with a little solid anethol. 



:{ ) This is evidently intended to convey that anethol may also be used for medicinal 

 purposes, (sol. p. +21 to +22°.) 



Bergamot oil (Oleum Bergamottce). Yellowish or greenish: di 5 o 0,880 

 to 0,886; « D to the right; evaporation residue 4 to 6°/o; with 0,5 vols of 

 90°/o alcohol should give a clear solution with a faintly acid reaction; 

 detonation with iodine 1 ). 



2 ) Such tests are quite valueless for the estimation of essential oils; in the following 

 paragraphs, therefore, they have been altogether disregarded. 



Cajuput oil (Oleum Cajuputi). Bright green or yellowish; neutral 

 reaction; di 5 o 0,915 to 0,930; soluble in alcohol and ether, not soluble in 

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

 water and 10 drops nitric acid, the mixture may not turn blue upon 

 the addition of excess of ammonia. 



2 ) All essential oils are soluble in carbon disulphide; if any cloudiness occurs, it pro- 

 ceeds from an unavoidable presence in the oil of a certain proportion of water caused by the 

 process of manufacture ; this cloudiness is immediately removed by the use of dehydrating 

 agents, such as anhydrous sodium sulphate. 



Camphor (Camphora). Crystalline, white, transparent pieces or crys- 

 talline powder; di 5 o 0,990 to 0,995*); m. p. 175°, readily soluble in alcohol, 

 ether, chloroform, fixed or essential oil; insoluble in water. 



*) This indication is superfluous, especially because nothing is said in the Pharmacopoeia 

 concerning the method by which this difficult estimation is to be carried out. 



Clove oil (Oleum Caryophyllorum). Brownish 1 ); di 5 o 1,045 to 1,070; 

 b. p. 250 to 260°; soluble in 2 vols, of 70°/o alcohol. 



*) The colour of clove oil is yellowish, becoming darker with age. 



Fennel oil (Oleum Fceniculi). Colourless or yellowish; di 50 0,965 

 to 0,985; « D to the right; solidifies at -f- 3° into a crystalline mass 1 ); sol- 



9* 



