SECT. XIII. OILS. 



avellana, or Juglans rcgia, the Hazel-nut, or Wal- 

 nut. The kernel is first slightly roasted, and the 

 oil then expressed. It is used in paintings of a 

 coarser sort ; and also in the seasoning of food by 

 many of the inhabitants of the middle departments 

 of France ; but it is apt to become rancid. 3dly, 

 Poppy oil is extracted from the seeds of Papaver 

 somniferum, which is cultivated in France for this 

 purpose. It is clear and transparent, and dries 

 readily ; and when pure it is without taste or odour. 

 It is used for the same purposes as the Olive oil, for 

 which it is often sold, and possesses nothing of the 

 narcotic properties of the Poppy. 4th ly, Hemp- 

 seed oil is extracted from the seed of the Hemp. It 

 has a harsh and disagreeable taste, and is used only 

 by painters. 



SUBSECTION II. 



Volatile. Oils. Volatile Oils, which are known 

 also by the name of essential oils, arc of very 

 common occurence in the vegetable kingdom, and 

 are found in almost all the different organs of the 

 plant. They are found in many roots, to which they whence , 

 communicate a fragrant and aromatic odour, with a Ol 

 taste somewhat acrid. The roots of Imda Ihlc- 

 111111)1) Genista canariensis, and a variety of other 

 plants, contain essential oils. They are found 

 also in the bark, as in that of Launts Cinamomum ; 

 in the wood, as in that of Lauras Sassafras and 



