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Savin Oil {Oleum sabznae). Mobile when in fresh condition; 

 colourless or yellowish, in course of time becoming dark and viscid; 

 di5° 0,910 to 0,930; soluble in an equal volume alcohol. 



Spearmint Oil (Oleum menthae crispae). Colourless, yellowish 

 or greenish yellow; d^o 0,920 to 0,940; soluble in every proportion 

 in alcohol 1 ); does not decrepitate with iodine 2 ). 



*) The oil forms with go per cent, alcohol a solution which is clear only in 

 the beginning; when more alcohol is added, opalescence occurs. 



2) This reaction is valueless and superfluous. 



Spike Oil (Oleum spicae). Colourless 1 ) or green-yellowish; d^o 

 0,905 to 0,915; soluble in 1,7 to 2,6 parts dilute alcohol, clear or 

 with slight turbidity 2 ). 



1 ) Spike oil is never colourless, but always yellowish. 



2 ) Even a slight turbidity should disappear immediately if more alcohol is 

 added, otherwise the oil is probably adulterated. 



Star-anise Oil (Oleum anisi stellati). Colourless or yellowish; 

 di 5 o 0,980 to 0,990; solidifies at about -}-2 01 ); soluble in alcohol 2 ). 



1 ) The sol. p. of pure star-anise oil lies above -f- 14°; solidification must, if 

 need be, be started by inoculation with a small crystal of anethol. It is surprising 

 that such antiquated statements as the above continue to be found from time to 

 time in books, although they have been disproved long since. Umney, as long 

 ago as 1889, called attention to the incorrectness of the statement that star-anise 

 oil solidifies at -f- 2°, and we have also pointed it out repeatedly in our Reports. 



2 ) Star-anise oil dissolves in 1,5 to 3 vol. 90 per cent, alcohol. 



Tansy Oil (Oleum tanaceti). Yellow or greenish yellow, becomes 

 brownish on exposure to the light; diso 0,923 to 0,954; readily 

 soluble in alcohol. 



Valerian Oil (Oleum Valerianae). Somewhat viscid 1 ); brownish 

 or greenish yellow; d^o 0,930 to 0,960; readily soluble in alcohol; 

 the solution has an acid reaction. If 1 drop of the oil is dissolved 

 in 20 drops carbon disulphide, shaken with 1 drop sulphuric acid, 

 and then 1 drop nitric acid added, the carbon disulphide acquires 

 a deep-blue or violet colour if shaking is continued 2 ). 



1 ) Valerian oil in fresh condition is mobile. 



2 ) Such reactions are absolutely valueless for estimating essential oils. 



Wild Thyme Oil (Oleum serpylli). Colourless to golden yellow; 

 di5° 0,890 to 0,920; soluble in alcohol in every proportion. 



Wintergreen Oil a) natural (Oleum gaultheriae) 1 ). Colourless, 

 yellowish or reddish; di5o 1,180 to 1,187; readily soluble in alcohol- 

 identity reactions. 



b) artificial (Methylum salicylicum). Colourless; d^o 1,1819 2 ); 

 b. p. 220 ; readily soluble in alcohol; identity reaction with ferric chloride. 



*) Natural oil of wintergreen is obtained from two different plants : Gaultheria 

 procumbens L. and Betula lenta L. The two oils are of absolutely equal value. 



2 ) The spec. grav. is incorrectly given, and should be di5° 1,185 to 1,190. 



