34 



EGGS IN COLD STORAGE. 



Answers to 

 Query 3. 



Gravity air 

 circulation. 



In reply to Question 3, about a dozen state that 

 they are using- some form of mechanical forced cir- 

 culation. The advantages of this method will be 

 discussed quite fully later on. About double this 

 number are using- the small electric fans. These 

 also will be treated in the discussion of mechanical 

 air circulation in another chapter. 



As air circulation is a somewhat neglected subject, 

 and comparatively few have experimented enough to 

 have positive opinions, based upon practical expe- 

 rience, reg-arding- the merits of different devices and 

 methods, some of the more prominent and successful 

 ones are illustrated and discussed in this article. 



In considering- the following- outlined arrange- 

 ments of piping- in the storag-e room and the various 

 locations of screens, partitions, etc., in combination 

 with the coils, for the purpose of separating- the 

 warm and cold currents of air (the one on its way 

 upward from lower part of room to the top of 

 cooling- coils; the other downward from cooling- 

 coil toward floor), the principle on which this 

 movement of air operates should be noted, so 

 that the underlying- law may be understood. The 

 cause of a circulation of air in a storag-e room with 

 direct piping- is a variation of temperature, which 

 causes a difference in weig-ht of the air in different 

 portions of the room. The air in the immediate 

 vicinity of the pipes is cooled to a lower temperature 

 than in the balance of the room, causing- it to drop 

 toward the floor by reason of its greater specific 

 gravity what is designated as gravity air circulation. 

 Just as long- as the flow of the refrig-erant is main- 

 tained within the cooling- pipes, the air will circulate 

 by the action of gravity, the lig-hter warm air in top 

 of room descending- to replace the air in contact with 

 pipes, which falls, as cooled, toward the floor. Should 

 the refrig-erant passing- through coils be shut off, the 

 cooling effect is checked, and as a result air circula- 



