352 ODOHOGRAPHIA. 



Tussilago farfara. Its taste is at first burning and sweetish, after- 

 wards aromatic. It burns with a bhie, slightly fuliginous flame, 

 giving oft' strong smelling vapours which excite coughing, and 

 leaves a small quantity of charcoal. It dissolves sparingly in 

 water, easily in alcohol and ether.* 



Ferment oil of Urtica urens ("The Small Xettle"), obtained as 

 above, but from the fresh, flowering plant, which during fermenta- 

 tion emits first a vinous, then a sharp and intoxicating odour. It 

 resembles the ferment oil of Echium vulgare.-f 



Ferment oil of Vitis vinifera (the Grape Vine). Fermented 

 vine leaves are distilled, the distillate cohobated ; the result of the 

 second distillation abstracted with ether, and after evaporation of 

 the ether the oil remains as usual. It is pale yellow, lighter than 

 water, has a peculiar vinous odour like vine-Jloivers and mignonette, 

 and a burning, sweetish, aromatic taste. It reddens litmus slightly 

 but permanently. It evaporates in the air, diffusing a strong 

 odour. Heated with fuming nitric acid it resinifies and assumes 

 a crrass-green colour. With sulphuric acid it forms first a white, 

 then a light red, and ultimately a brown mixture, without losing 

 its odour. It is not deodorised by agitation with chlorine water. 

 With aqueous potash it forms a clear mixture from wdiich the oil 

 afterwards separates with red-brown colour, but with its original 

 odour. It dissolves sparingly in water, abundantly in alcohol, 

 ether and fixed oils. With oil of turpentine and oil of lemon it 

 forms at first a milky solution, which afterwards becomes clear. J 



Ferment oil of Diseased Apples— " Mai oil," Oil of Apples. 

 This is formed or produced by cellulostasis, a disease of the apple 

 which imparts a mushy odour to that fruit. It is obtained from 

 the diseased apples by distillation with water. It is yellowish- 

 grey, lighter than water, and boils at 109^ C. Smells of musk ; 

 tastes rough and sharp. It is found on analysis to contain 64' 15 

 per cent. C, 20-65 H, 1515 and 0-05 X. It volatilises completely 

 when heated. It dissolves readily in alcohol and ether, and 

 imparts a musk-like odour to water. § 



* Bley, Jahhr. der Pharin., ii., p. 207. 



t Bley, N. B. Arcliiv., xxx., p. 167. 



X Bley, Rep. Pliann., Ixviii., p. 801. 



§ Kossignon, Journ de Pharni., xxvii., p. 158. 



