142 THE OLIVE 



properly used, the amount of pressure required may be exactly 

 graduated. In the first pressure, usage differs as to the employment 

 of water. • It must be clearly understood, that the olive berry con- 

 tains a large amount of water from which the oil separates itself 

 when the mixed liquid is allowed to rest after the expression, and 

 that the employment of water is not for an adulteration, or other 

 improper purpose, but simply to free the oil and water in the berry 

 and ease the process of pressing. Doubtless oil extracted w^ithout 

 the use of water is appreciably finer to an expert ''olive oil taster," 

 but it is doubtful if very much of such oil reaches the market. 

 The usage of mills differs. The most extreme divisions of oils 

 would be, that of the first crusliing and the first pressure ; that of 

 the same pomace crushed a second time ; that of the same pomace 

 treated with cold water ; that of the same pomace treated with hot 

 water ; that of this pomace ground fine, placed in an agitator and 

 heated with water, until the stones fall to the bottom and are 

 caitied away, and tha water and lighter matter passed into settling 

 tanks, where the oil is skimmed off, w^iile a little more is made by 

 another pressure; this is called washed oil. This same pomace in- 

 stead of being treated as above, may be treated by the bi-sulphate of 

 carbon process at special factories, with a larger percentage of oil as 

 a result. Finally a low grade of oil is skimmed from the w^ater used 

 in collecting the oil, and which is carried out of the mill and de- 

 posited in tanks called from the low quality of the oil, " the inferno." 

 The term ''Virgin oil'' is used so variously, that it is difficult to 

 define it with accuracy. It is used for the^r^^i^ run of oil w^hether 

 made with or without water ; it is also sometimes used for early oil 

 — the first of the season ; the most exact use seems to be the oil 

 which flows either without any pressure by the weight of the pom- 

 ace in the racks or the cages, or just as the pressure begins to tell. 

 Watching the press one sees pure oil and water run out, and if this 

 is taken from the receiver at once, the oil and water separate quick- 

 ly, and the oil is exceedingly rich and fine. As the pressure goes 



