172 REFRIGERATION AND ITS USES 



had decayed and was lost. Similarly, the production of eggs 

 is much greater during the spring and early summer than 

 at other seasons of the year. Formerly the supply of eggs 

 during the spring was so greatly in excess of the demand that 

 the price fell to a ridiculously low mark, and many eggs even 

 went to waste. During the winter months, on the other hand, 

 eggs were often practically unobtainable at any price. Since 

 the advent of cold storage, however, many kinds of fruit, eggs, 

 and other kinds of perishable produce, are obtainable at any 

 season of the year and at prices which vary but little from 

 season to season. In this and other ways, cold storage has 

 greatly modified modern life. 



201. Construction of a Cold Storage Plant. A modern 

 cold storage plant so closely resembles an ice plant that no 

 extensive explanation is necessary. The plant consists of a 

 compressor, A, operated by a steam engine, B (Fig. 127). 

 The ammonia is cooled and liquefied in the cooling coils, C. 

 It then collects in the reservoir, D, and finally is permitted to 

 pass through the regulating valve, E. The "high side," then, 

 is exactly like the "high side" of a manufactured ice plant. 

 After passing through the valve, E, the ammonia vaporizes 

 in the pipes submerged in the brine in the vat, F. After 

 vaporizing, the ammonia returns to the compressor through 

 the pipe, c-c. Thus we see that the "low side" is also the 

 same as in the case of the ice plant. The brine vat, however, 

 is not usually within the storage room at all. The chilled 

 brine is forced by the pump, G, through the pipe, d-d, to 

 the absorbing coils, H and H, in the storage rooms. After 

 passing through these coils, the brine returns to the vat, F. 



202. Temperature Required for Cold Storage and How 

 Controlled. Different kinds of produce keep best when stored 

 at different temperatures. Some fruits are usually stored at 

 about 36F.; others at about 32F.; fresh meat at about 25F.; 

 poultry at about 15F.; and fish at about 0F. To obtain a 

 given temperature in the storage room it is necessary that 

 the boiling point of ammonia be controlled. 



