TRANSPORTATION OF CITRUS FRUIT FROM PORTO RICO 
17 
perature, other things being equal, the more rapidly the heat is trans- 
ferred. It would seem, therefore, if the center of the cargo is to be 
cooled quickly provision must be made for the passage of the refrig- 
erant, cooled air, in and around the boxes. It would seem also that 
the more open the stowage, so as to allow access of the air to the 
loading, the more quickly the fruit will be cooled down. Evidence 
on this point was gained in the dunnage experiments already men- 
tioned, which were made on all four trips. The results of these 
Fig. 8. — Average temperatures for four trips of the top, bottom, and middle layers 
of fruit in the dunnage test. Two different methods of placing dunnage are com- 
pared with fruit stacked without dunnage 
experiments are shown in Figure 8, giving averages of all the tests. 
The fruit with which these experiments were made was loaded at 
several points on the island, the last point of loading being San Juan. 
For this reason the average fruit temperatures were calculated from 
readings made at the end of loading at this point. Had they been 
calculated from readings made at points of loading prior to this they 
would be misleading and not comparable, since readings made at an 
earlier date and under different conditions would have to be com- 
pared with readings made later on the trip. 
