— 8i — 



Thymol {Thymolum). Colourless cristals in the form of tablets; 

 melting point 50 to 5 1°; soluble in about 1100 parts water; readily 

 soluble in Spiritus, ether, chloroform, and also in soda liquor; solid 

 thymol sinks in water, but when melted it floats on the surface; 

 when evaporated on a water bath, 10 gr. thymol must leave no weigh - 

 able residue. Colour reactions. 



Turpentine Oil {Oleum terebmthince). Colourless or faintly 

 yellow; d 15 o 0,865 to 0,870*); commences to boil at 160 ; forms a 

 clear solution with about 8 parts Spiritus; it absorbs oxygen from the 

 air, and then becomes more viscid. 



*) The crude oil is frequently heavier, up to 0,877. 



2 ) Turpentine oil commences to boil at about 15 5 . 



Turpentine Oil, rectified {Oleum terebinthince rectificatum). 

 Colourless; di 5 o 0,860 to 0,870; boiling point 155 to 162 ; soluble in 

 about 7 parts Spiritus; the solution should not change litmus paper 

 moistened with water. 



Valerian Oil {Oleum Valeriana). Yellow-green or brown-yellow; 

 at first mobile, becoming more viscid in course of time; di 5 o 0,93 to 

 0,96; acid reaction; dissolves with difficulty in water, very readily in 



Spiritus. 



Spanish Pharmacopceia. 



(Farmacopea oficial espanola, septima edicion 1905.) 



On the new seventh edition of the Spanish Pharmacopceia, it is 

 unfortunately not possible, so far as concerns the articles which interest 

 us, to pronounce as favourable an opinion as on the other Pharma- 

 copoeias discussed in these pages. At first sight it no doubt appears 

 as if a modern spirit pervaded throughout the directions for testing, 

 as the Pharmacopceia even specifies definite demands for the optical 

 rotatory power of the oils; but on closer examination the exact op- 

 posite is found to be the case. For example, the rotations given are 

 partly entirely incorrect, and many of the other details are so anti- 

 quated that one involuntarily receives the impression that the know- 

 ledge of the progress made in the examination of essential oils during 

 the last 20 years, has not yet penetrated to Spain. This fact makes 

 it appear all the more desirable to discuss here the individual oils. 



In vain we have looked for information as to the temperature to 

 which the specific gravities mentioned for the various oils apply. 



As for other liquids they have all been taken at 15 , it may be 

 assumed that in the case of essential oils that temperature has also 

 been taken as a basis. For this reason we have in the following 

 pages judged the specific gravities in every case accordingly. 



6 



