544 



CALIFORNIA FRUITS: HOW TO GROW THEM 



It is interesting, therefore, to describe a machine evaporator con- 

 structed upon true principles and having a capacity sufficiently large 

 to encourage its use. Mr. L. W. Parsons of Campbell, Santa Clara 

 county, has given most of his life to the design and construction of 

 fruit evaporators, and secured patents thereupon which have ex- 

 pired and are now public property. In the Pacific Rural Press of 

 June 19 and 26, 1909, he gave his conclusions on the desirability 

 of machine evaporation and a design for the construction of an 

 evaporator which embodied all his best work in this line. The ac- 

 companying drawings and description are from Mr. Parson's writ- 

 ings : 



A fruit drying chamber capable of holding about two tons is about as large 

 as one heater can well handle. Wire trays two feet wide by five feet long 

 are as large as one strong man can conveniently handle; he might prefer them 

 shorter; in fact, if the smaller tray would give a drier with sufficient capacity 

 to meet the demands of the owner, he could make the trays two by four feet, 

 with a narrower furnace, to correspond. Where two men are always avail- 

 able, trays three by six feet have been found to work well. 



A drier five feet wide and twenty-four feet long, having ten trays in its 

 length and twelve trays high, holds 120 trays 2 by 5 feet, or a total drying 

 surface of 1,200 square feet, which at the rate of 3 pounds per foot give a 

 total of 3,600 pounds at one time: that is, it would take that much gross 

 weight of fruit before cutting to fill the trays. Large fruit would amount to 

 more, and small fruit or culls might not go above two pounds to the foot. 



By making the drier one or two trays longer and higher, and a foot or so 

 wider, the capacity may be materially increased. But if much more capacity is 

 desired, it would be better to build another drier, or several of them, alongside 

 of it, which would work satisfactorily. 



The fruit drying chamber rests on top of the hot air chamber, which is 

 surrounded by brick or cement walls about eight inches thick, and is as long 

 and wide as the fruit chamber above. The height of these walls depends on 

 the size and shape of the heater enclosed by them. The furnace is a very im- 

 portant factor : it must be strong, not easily burned out, smoke-tight in all 

 rts joints and flues, with caps or covers so placed to facilitate cleaning out 

 soot and ashes. There must be room between the sides of the furnace and 

 the. side walls to allow for circulation of the air to be heated. 



Fresh air enters this hot air chamber through openings about a foot square 

 at the bottom in front between the furnace and the side walls ; passes along 

 on the sides and top of furnace and flues until it reaches the back end of the 

 hot air chamber, where it passes up through an opening into the fruit chamber 

 above. 



The next, and perhaps the most critical, part in the construction, is the 

 sheet iron floor which covers the furnace and flues and separates them from 

 the fruit chamber above. This iron floor is made of either black or galvanized 

 iron, not thinner than No. 24; thicker would be better. It rests on rods or 

 bars of angle or T iron stretched from wall to wall, with ends built into the 

 walls. These rods are spaced about two feet apart. The sheets of iron should 

 be riveted or bolted together. The edges of this iron floor should project into 

 and be imbedded in the brick walls in front and along the two side walls as 

 far back as the floor goes to the other end of the drier. Cover this floor 

 with an inch or so of sand or fine earth, so as to stop up all cracks. At the 

 back end of drier this iron floor is cut short one foot, allowing an opening of 

 one by about five feet to allow the hot air from the heater below the iron 

 floor to pass up into the fruit chamber above. This floor must be made tight 

 everywhere, so no hot air can possibly leak upward and scorch the fruit or the 

 woodwork above. 



The brick walls should be built about eighteen inches above the iron floor, 

 so that the wooden frame which rests on top will be safe from burning. 



