57 



CHAPTER X. 



PURIFICATION. 



The oil in its crude state contains impurities of various 

 kinds, albuminous, mucilaginous, and other ; and to 

 render it clear and fit for its various uses, and conse- 

 quently marketable, various methods are used. Simple 

 settlement appears to be the process, if it can be so 

 called, most in vogue ; but hot air or steam, and 

 infusion of nut galls are resorted to as purifying mediums. 



The Arabs produce excellent oil, knowing no other 

 means of clarifying than by settlement in cisterns or 



McGulloch gives the following interesting account 

 of the clarifying process, referred to in the last chapter, 

 at Gallipoli : — 



" Gallipoli supplies England, Holland, the north of 

 " Europe, and, in short, all those countries that require 

 " the most perfectly purified oil. It is clarified to the 

 66 highest degree, by merely keeping it in cisterns 

 " hollowed out of the rock on which the town is built. 

 " The voyages it has to perform being long, it is put into 

 " casks so well constructed, that it frequently arrives at 

 " Petersburg in the heat of summer without the least 

 " waste or leakage, an advantage attributed to the 

 <e seasoning of the staves, which, before they are put 

 " together, are well soaked in sea water. 



" We borrow the following details with respect to 

 " the preparation of oil at Gallipoli from a very interest- 

 <€ ing paper by an English gentleman who had resided 

 " in the town. 



" The rock on which the town is built is easily 

 <e excavated ; and in caverns thus constructed oil clarifies 

 " sooner* and keeps without rancidity much longer than 



