— 127 — 



Anise Oil, Russian. (Oleum Anisi) 1 ). Colourless or pale yellow; 

 d 20 o 0,980 to 0,990; « D to the left up to — 2°; sol. p. 15 to 19° 2 ); 

 soluble in 3 vols, alcohol. 



*) Anethol, which was incorporated in the 4 th Ed. of the P. G. is again replaced by anise 

 oil, probably because anethol has given cause for complaint on account of its frequent separation 

 in crystal-form from aqueous mixtures. Several years ago (Report October 1906, 11) we 

 mentioned this fact, and we can only repeat now that when a really good anise oil is used 

 exactly the same experience will be made as with anethol, for which reason the change will 

 probably fail to achieve its object. It would therefore have been more to the point if the 

 useless prescription of Liq. ammon. anis., which is chiefly concerned in this matter, had been 

 altered, instead of anise oil being substituted for anethol ! Also compare the introductory 

 paragraph, p. 125. 



2 ) When the oil is badly kept or has been repeatedly melted the cong. p. is gradually 

 reduced, while at the same time the sp. gr. increases. Comp. Report October 1904, 42. 



Benzaldehyde (Benzaldehyd). Colourless or slightly yellowish, of a 

 peculiar odour 1 ); di 5 o 1,046 to 1,050 2 ); b. p. 177 to 179°; soluble in 300 pts. 

 of water and in any proportion in alcohol or ether. Test for absence of 

 chlorine compounds, hydrocyanic acid, and nitrobenzene. 



x ) The odour resembles that of bitter almond oil. 



2 ) This indication is incorrect: pure benzaldehyde has a sp. gr. (at 15°) of 1,050 to 1,055. 

 When air is allowed access it absorbs oxygen and becomes gradually converted into benzoic 

 acid, thereby acquiring greater sp. gr., a process which is quite unavoidable where benzaldehyde 

 is being used up by degrees, for it can only be kept without alteration in entirely filled, firmly 

 stoppered, dark-blue bottles. When the benzoic acid content is large it separates out in 

 crystal form. 



Calamus Oil (Oleum Calanii) Viscous, yellowish brown; di 5 o 0,960 to 

 0,970; « D + 9 to +31°; soluble in alcohol in almost any proportion; an 

 alcoholic solution 1 : 1 acquires a reddish to dark-brown colour upon the 

 addition of 1 drop of solution of chloride of iron. 



Camphor (Camphora). Colourless or white, crystalline, soft pieces^ 

 or white crystalline powder. Dextrorotatory, [«] D20 o + 44,22° in a 20°/ 

 solution in absolute alcohol; m. p. 175 to 179°; volatilises upon heating 

 without leaving a residue, burns with a sooty flame. Very sparingly soluble 

 in water, readily soluble in ether, chloroform, alcohol, and oils. 



Caraway Oil (Oleum Carvi) 1 ). Colourless, turns yellow with age; 

 d 15 o 0,907 to 0,915; « D + 70 to +80°; sol. in its own vol. of alcohol. 



J ) On the substitution of caraway oil foir carvone, see introductory paragraph, p. 125. 



Cinnamon Oil, Ceylon (Oleum Cinnamomi). Bright yellow; di 5 o 1,023 to 

 1,040; « D faintly to the left, up to — 1°; soluble in 3 vols, of dilute alcohol; 

 cinnamic aldehyde content 60 to 76%. 



Clove Oil (Oleum Caryophyllorum). Nearly colourless or yellowish; 

 turning brown when exposed to air: di 5 o 1,044 to 1,070, « D to the left, up 

 to — 1,25 Q1 ), soluble in about 2 vols of dilute alcohol 2 ). 



J ) We have observed up to — 1,60° in our own distillates. 



2 ) The determination of eugenol by shaking with a 3% solution might perhaps have 

 been included also. The eugenol-content should not fall below 80°/o. 



