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CALIFORNIA FRUITS: HOW TO GROW THEM 



Crushing. The olives are usually crushed by heavy stone roll- 

 ers revolving in a circular depression in a bed of masonry into 

 which the fruit is placed. Crushers with corrugated bronze or 

 bronzed metal rollers are now made that perform their work in a 

 very satisfactory manner, breaking up the flesh and pits very 

 thoroughly. As they are all of metal they absorb no oil and are 

 easily cleaned. It is very essential that the flesh should be crushed 

 thoroughly in order to break up the cells and permit the oil to be 

 pressed out. 



Pressing. When the revolving crusher has reduced the olives 

 to a mass, the pomace is shoveled up from the bed of the mill 

 and prepared for pressing. Instead of the fabric of woven esparto 

 grass which is used abroad, coarse linen cloth is used. A certain 

 amount of the pulp is put in each cloth, so that when the cloth is 

 folded back it makes a cheese about three feet square and three 

 inches thick. Ten or more of these cheeses are placed one above 

 the other, with slats between, and the pressure applied gently at 

 first. From the liquid which runs out first is made the very finest 

 oil, known as "virgin oil." The pressure is then increased very 

 gradually until the full power of the machine is reached. This 

 presses out the second quality of oil, which is generally mixed 

 with the first. After obtaining all the oil possible by the first 

 pressure the "cheese" is taken out, thoroughly broken up in hot 

 water, and again pressed. This yields the third quality, which 

 is very much inferior to the first and second. Sometimes the 

 "cheese" from the first pressing is thoroughly broken up with 

 cold water and pressed .again before being treated with hot water. 

 In this way a little oil is obtained that differs little from the sec- 

 ond quality, and may be mixed with it. After this a certain amount 

 of oil still remains in the "cheese," but it can be extracted only 

 by very powerful hydraulic presses, or by chemical means, and 

 then is of very inferior quality, and suitable only for burning 

 or for soap making. 



Settling and Clarifying. The liquid from the press is dark 

 colored, and it is conducted into a receptacle for settling. Much 

 of the foreign matter quickly separates, the oil appearing on the 

 top. The oil is removed to other receptacles in which it can stand-, 

 from two to five months for perfect separation of undesirable, 

 sediment. These settling tanks may be of well-tinned metal, or 

 of cement lined with glass or other impervious substance. The 

 first settling is conveniently made by means of a funnel-shaped 

 apparatus, which by its conical shape facilitates the rapid deposi- 

 tion of sediment. After standing for twenty-four hours in this 

 apparatus the major part of the sediment is deposited and can 

 be drawn off at the bottom. It is well, before running the oil 

 into the settling tanks, to pass it through two or three inches of 



