270 POPULAR ECONOMIC BOTANY. 



it must necessarily be poisonous. Since this fallacy lias 

 been exposed, and the prohibition removed, poppy-oil has 

 been much used in Prance as a substitute for olive oil, both 

 in the manufactures and for table use ; and latterly several 

 imports of the oil have been received in this country. 



Ground Nut. Arachis hypogea. (Nat. Ord. Legumi- 

 nosce.) (Plate VI. fig. 31.) Large consignments of this 

 seed are from time to time received from the African coast 

 for the expression of oil. The produce is a fine thin straw- 

 coloured oil, resembling poppy oil and the finer varieties of 

 oil of olives. The oil itself has been imported occasionally, 

 but in small quantities. It is very free from stearine, and 

 is consequently used extensively by watch-makers and others 

 for delicate machinery. In India its use in cooking and 

 for the table is very extensive; it is there called Katchung 

 Oil. 



Several other seeds are used for the expression of their 

 oil ; thus, the common Hazel-nut, Corylus Avellana, which 

 yields a fine limpid oil, so free from stearine, that it is pre- 

 ferred before all others for watch machinery. Its value in 

 this respect can hardly be too highly rated, for independent 

 of its perfect liquidity, it is slow in drying, consequently 

 requiring only an occasional renewal. To this quality 



