104 MODERN" FRI T IT MARKETING 



idly is the heat taken up, and a lower temperature can 

 be maintained in the storage room. 



The cost of maintaining- a low temperature for the 

 storage of fruit is difficult to estimate, owing to the vary- 

 ing local conditions, but for properly constructed and 

 insulated storage houses using the ice-brine system, the 

 cost should not exceed $10 per 1,000 cubic feet per 

 month. A thousand cubic feet will accommodate one 

 carload of produce. 



Cooling Solutions Used. It is obvious that in such 

 a system some liquid would have to be used which would 

 not freeze at the ordinary temperature. For this pur- 

 pose two different substances have been used. One is 

 the common solution of salt brine; the other is a solu- 

 tion of calcium chloride in water. Salt solution was 

 the one most used in the earlier development of this 

 system, but it is now largely superseded by the calcium 

 chloride. A saturated solution of salt and water will 

 freeze at a temperature of about 7 degrees F.,=below 

 zero, while a similar solution of calcium chloride will 

 not crystallize under 50 degrees F. ; hence the latter is 

 better adapted for maintaining a lower temperature. In 

 addition to this, the salt very quickly corrodes the pipes 

 which need to be replaced every four or five years, while 

 with the calcium chloride solution replacing once in ten 

 years is sufficient. For determining the proper density of 

 the solution a common hydrometer similar to the one used 

 in testing lime sulphur solution could be used. For a 

 salt brine solution a 25-degree reading on the hydro- 

 meter would be about right, while for the calcium chlo- 

 ride 20 degrees or a little less could be used. 



