86 Report of Schimmel $ Co. April/October 1917. 



Wild Thyme Oil (Oleum Serpylli). Colourless to golden-yellow; di 6 o 0.890 to 

 0.920; « D — 10 to — 20 01 ); soluble in every volume of alcohol. 



x ) Even — 21° have been observed. 



Vanilline (VanUlinum). Fine crystal-needles; soluble in 80 to 100 parts of water 

 of 15° and in 20 parts of 75 to 80°; easily soluble in alcohol, ether, and chloroform; 

 melting point 81 to 82°; combustion-residue at the utmost 0.1 percent.; the aqueous 

 and alcoholic solution of vanilline turns blue on adding ferric chloride solution; 0.1 g. 

 of vanilline ought to dissolve in 2 ccm. of sulphuric acid, when heated gently, giving 

 a clear solution of a light yellow colour and without leaving any residue. 



Wintergreen Oil (Oleum Gaultherice). Colourless, yellowish or reddish; di 5 o 1.180 

 to 1.193; « D + 0° or slightly lasvorotatory, up to — 1 °; soluble in 5 to 8 vols, of dilute 

 alcohol; 1 ccm. of wintergreen oil' ought, on mixing with 10 ccm. of a 5 per cent, caustic 

 potash solution, to give a colourless or at least only slightly yellowish solution; test 

 for identification by means of ferric chloride. 



Wintergreen Oil, artificial, see Methyl salicylate. 



Wormseed Oil, American (Oleum Chenopodii anthelmintici). Colourless to yellowish ; 

 d 16 o 0.965 to 0.990 and higher; « D — 4 to —8.9°; soluble in 3 to 10 vols, of 70 per cent, 

 alcohol. 



Wormwood Oil (Oleum Absinthii). Rather viscous; generally of a dark-green 

 colour, occasionally also blue or brown; d 15 o 0.900 to 0.955. 



In a discussion of the Ph. G. ed. V, G. Frerichs 1 ) also refers to the estimation of oil 

 of cinnamon, for which purpose the Pharmacopoeia requires a sodium bisulphite solution 

 of about 30 per cent. According to Frerichs, it would be practical to add that the 

 solution must be prepared afresh in each case and should also be filtered. Commercial 

 sodium bisulphite is mostly lumpy and only dissolves very slowly in cold water; 

 accordingly, it is advisable to pound it in a mortar beforehand. The solution ought 

 in no case to be heated. About 60 g. of the solution are required for every determ- 

 ination. The best way is to dissolve 25 g. of powdered sodium bisulphite in 45 g. 

 of cold water, in which manner one can easily obtain the necessary quantity of filtered 

 solution. 



In carrying out the determination, it is imperative to shake the solution during 

 the heating process frequently and steadily. When the undissolved oil has been 

 brought into the neck of the little flask, the latter must still be heated for some time, 

 being kept submerged half-way up the neck. Observations ought only to be noted 

 after the apparatus has cooled down. The neck of the little flask ought to be adjusted 

 for practical purposes in such a manner that the 50 ccm. mark is in the middle of 

 the neck, from which point the latter ought to be divided into Vio ccm. to a length of 

 52 ccm. upwards and 48 ccm. downwards. 



In carrying out the determination, the aqueous liquid ought to be filled up to the 

 50 ccm. mark during the heating process, because under these circumstances the 

 undissolved oil is to be found within the scale after cooling down. The interior 

 diameter of the neck may be about 10 mm. The little flask can also be used for 

 other purposes as a measuring flask. The graduation of the neck, just mentioned, 

 renders it also suitable for testing oil of thyme. 



l )-Apotheker Ztg. 32 (1917), 341, 347. 



