250 STORING FRUIT 



fore much, better to build a good-sized plant to begin with. 

 It can never be done as cheaply afterwards. 



7. Operation Inexpensive. — The building must be operated 

 cheaply. This is imperative. The more simple the method of 

 operating the better. A method requiring expensive machinery 

 that is likely to get out of repair and which needs the attention 

 of expert and high-priced men, while it may be all right for 

 the large city plant, is certainly not usually the best for the 

 farmer unless he is a large grower. 



The various typts of fruit storage may be classified as 

 follows : 



1. Refrigerated storage, in which ammonia, carbon dioxide 

 or some other gas is used for cooling the room. This is the most 

 common type with large establishments and has the advantage 

 that it is usually very accurate in operation. It is possible to 

 regulate the temperature to a degree, which is often very im- 

 portant. The objections to it are that it is expensive and that 

 the machinery required to operate it is rather complicated and 

 when it gets out of order requires an expert to fix it up again. 

 There are three different methods of cooling storage rooms by 

 this gas system: {a) The gas, after being liquefied under 

 pressure, is conducted in pipes to the storage room which is 

 to be cooled, and there allowed to expand and take up the heat 

 of the room; (&) the gas is allowed to expand in pipes which 

 are immersed in brine and this cooled brine is then conducted to 

 the room to be cooled; (c) the air of a certain room (or rooms) 

 is cooled down and then is put in circulation by fans and carried 

 thus to the storage rooms. 



2. We have refrigerated storage where ice is used for cool- 

 ing. This is the type of storage which is often used for fruit, 

 and it has proved an exceptionally satisfactory method for this 

 purpose. The method is briefly as follows: At the top of the 

 building are vats in which are located coils of pipes filled with 

 chloride of calcium brine. This brine is 25° Beaume density 

 and will not freeze at 3° F. These coils, known technically as 

 the primary coils, are connected by pipes with other coils in the 

 rooms to be refrigerated, known technically as the secondary 



