HANDLING LETTUCE AND CELERY. 
21 
crept slowly up to 41° F., and also how it remained at that point for 
almost two days in spite of large fluctuations in the outside tempera- 
ture. It then began to drop below 40° F. again, owing to the cold 
outside temperature that the car encountered in the North. 
The nonprecooled car was loaded on March 4 and started with a 
temperature of 62.5° F. It is interesting to note how very slowly 
the temperature of the celery in this car was lowered under the 
influence of ice alone. It was almost four days after leaving its 
starting point before it had reached as low a point as the precooled 
car maintained for the entire trip. It is during the first few days, 
as previously explained, that the damage by high temperatures is 
done. Subsequent cooling may prevent only further deterioration. 
Figure 15 indicates the average temperature in the top and bottom 
tiers in both cars. It should be noted that during the entire trip the 
Fig. 15.— Diagram illustrating the average temperatures (°F.) of celery in the top and in the bottom 
layers of crates in carloads in transit from Florida to New York, season of 1915. 
temperature of the top tier in the nonprecooled car was 10 degrees 
or more higher than the bottom tier. For a large part of the trip, 
the differences amounted to about 18 degrees. The precooled car, on 
the other hand, had only a difference of 5 or 6 degrees between the 
top and bottom tiers during the whole trip. The temperature in 
the bottom of the nonprecooled car went slightly below that of the 
precooled car after the third day, owing, no doubt, to the several 
reicings that it received in transit. The important point, however, 
is the fact that the temperature of the top tier in the nonprecooled car 
was far above that of the precooled car for the entire trip and even 
upon its arrival at its destination was still 5 degrees higher than the 
top tier of the precooled car. This seems to indicate that even after 
